Materials science Books

Book SynopsisThis book deals with all aspects of advanced composite materials; what they are, where they are used, how they are made, their properties, how they are designed and analyzed, and how they perform in-service. It covers both continuous and discontinuous fiber composites fabricated from polymer, metal, and ceramic matrices, with an emphasis on continuous fiber polymer matrix composites.The unique feature of this book is that it provides a comprehensive overview of composite materials at the introductory to intermediate level from an industrial perspective. Other books on composite materials stress theory more than practical applications. Throughout this book, practical aspects—based on the author's 38 years of industrial experience—are emphasized more than theory.

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Book SynopsisThis volume considers the most common materials used in medical devices. State-of-the-art reference information is given for implant materials including stainless steels, cobalt-base alloys, titanium, shape memory alloys, noble metals, ceramics, and polymers. Examples of materials- and mechanical-based failures of medical devices provide lessons learned in the failure analysis section. Biotribology and implant wear are covered extensively, including clinical wear and biological aspects of implant wear. A detailed look at corrosion includes its effects, corrosion products, mechanically assisted corrosion and corrosion fatigue. Biocompatibility is also discussed at length including biocompatibility of ceramics and polymers. Engineers with little exposure to medical and biomedical engineering will find this book particularly useful. Volume 23 is a replacement for the Handbook of Materials for Medical Devices edited by J.R. Davis (ASM, 2003). The new volume features brand-new content that greatly expands the scope and depth of coverage, including a more in-depth discussion of materials and focus on applications.

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Book SynopsisThis book emphasises the physical and practical aspects of fatigue and fracture. It covers mechanical properties of materials, differences between ductile and brittle fractures, fracture mechanics, the basics of fatigue, structural joints, high temperature failures, wear, environmentally-induced failures, and steps in the failure analysis process. Separate chapters are devoted to fatigue and fracture of steels, aluminum alloys, titanium and titanium alloys, ceramics, polymers and continuous fiber polymer matrix composites.

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Book SynopsisVolume 4B expands coverage on equipment, control, troubleshooting, and problems associated with steel heat treating. New articles extensively address distortion and the prevention of cracking - including the modeling and simulation of distortion. Furnace equipment and controls are described in detail, along with quenching systems and characterization of quenchants for reliable and effective hardening. General process and procedure factors also are introduced - including temperature uniformity of furnaces, calculation of heat treating costs, decarburization, and more.

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Book SynopsisConference proceedings covering the latest technology developments for fossil fuel power plants, including nickel-based alloys for advanced ultrasupercritical power plants, materials for turbines, oxidation and corrosion, welding and weld performance, new alloys concepts, and creep and general topics.One hundred eighty-five participants representing 18 countries traveled from around the world to participate in the EPRI 7th International Conference on Advances in Materials Technology for Fossil Power Plants on the Big Island of Hawaii, USA. This conference built on the success of the previous 6 conferences originally started by Prof. R. (Vis) Viswanathan, EPRI (FASM) in 1995 in London (UK), and held every three years since that time in San Sebastian (Spain), Swansea, Wales (UK), Hilton Head Island (USA), Marco Island (USA), and Santa Fe (USA).This proceedings volume contains the largest number of papers ever collected for this conference. Overwhelming response to the 2013 conference (over a 20% increase in number of papers and technical talks) prompted the organizers to hold the first ever poster session. EPRI and ASM have again partnered to publish this proceedings which is organized into 9 topical areas: technology overviews, nickel-based alloys for advanced ultrasupercritical power plants, materials for turbines, alloys T23/24, Grades 91/92, oxidation and corrosion, welding and weld performance, new alloys concepts, and creep and general topics.

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Book SynopsisASM Handbook Volume 4D is packed with information and knowledge for anyone who uses or works with heat treated steels or cast irons. Written and reviewed by recognized authorities, this new handbook gives you in-depth articles with details on the processing and properties for all significant applications and types of heat treated ferrous alloys. New content includes not only updates on new alloys, but also expanded coverage on the effects of heat treating on the properties for more carbon and low-alloy steels, tool steels, stainless steels, and other high-alloy grades. New articles also describe important topics such as stainless steel surface hardening, heat treatment of steel gears, bearings, boron steels, and precipitation hardening copper steels, and more. From the basic principles of design, steel selection, and the importance of metallurgical structure on properties, this new handbook can help you work out heat treating solutions.

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Book SynopsisThe new 2016 edition of ASM Handbook, Volume 3: Alloy Phase Diagrams is a revision of the original 1992 edition. 40% of the volume has been updated and now includes 1083 binary systems, 1095 binary diagrams, 115 ternary systems, and 406 ternary diagrams. The revised volume provides a more complete explanation of phase diagrams and their significance with the addition of new material on solid solutions and phase transformations; thermodynamics; isomorphous, eutectic, peritectic, and monotectic alloy systems; solid-state transformations; and intermediate phases. Users of this volume will gain a better understanding of phase diagram construction and alloy system interactions while having a valuable resource to aid in their research and engineering pursuits.Since the 1992 edition of this volume was published, improvements in experimental techniques have increased the accuracy of results, filling the remaining gaps of existing systems. Increasingly sophisticated computer modeling methods determine phase equilibria that could not be determined experimentally in a practical manner — resulting in numerous revisions of previously accepted phase diagrams, and predicted phase diagrams for newly assessed systems.

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Book SynopsisThis new ASM Handbook, Volume 4E: Heat Treating of Nonferrous Alloys, completes the series of volumes on the major technological subject of heat treating. This singular work gives engineers, analysts, and technicians a one-stop source on the wide variety of nonferrous alloys. With expanded coverage on both the industrial practice and the science of heat treating, this new volume provides more practical information to guide processing requirements and the necessary background information for those without extensive prior knowledge.Table of ContentsGet the basics on heat treating with significantly expanded coverage on nonferrous alloys. In-depth articles provide details on the heat treating principles and practices of aluminum, copper, nickel, and titanium alloys. Quenching, distortion, residual stresses, and alloying effects are given special focus, and attention is given to the complexities of aging practices and microstructural development for the major and less common types of nonferrous alloys.

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Book SynopsisThis volume provides new and expanded coverage on the metallurgy, processing, fabrication, properties, and performance of aluminum alloys. It is the companion volume of ASM Handbook, Volume 2A: Aluminum Science and Technology, released in 2018. The aluminum alloy datasheets are designed for easy look up with details on key alloy metallurgy, processing effects on properties, and fabrication characteristics. In addition, outreach was done to identify and collect information on new alloy developments.Select handbook articles from ASM Handbook, Volume 2B: Properties and Selection of Aluminum Alloys have been published online first in ASM Handbooks Online in the ASM Digital Library in advance of the full volume release.Table of Contents Properties of Aluminum Alloys Significance of Mechanical Properties in Design and Application Aluminum Structural Design Fracture Resistance of Aluminum Alloys Fatigue of Aluminum Alloys Stress-Corrosion Cracking of Aluminum Alloy Corrosion of Aluminum and Aluminum Alloys Friction and Wear of Aluminum Alloys and Composites Wrought Aluminum Alloys A History of Wrought Aluminum Alloys and Applications Properties and Applications of Wrought Aluminum Alloys 1xxx Aluminum Datasheets 1060; 1100; and 1350 2xxx Alloy Datasheets 2014, 2014A, Alclad 2014; 2017, 2017A, and 2117; 2024, Alclad 2024; 2026; 2027; 2029 and Alclad; 2040; 2050; 2055; 2065; 2099; 2124; 2195; 2196 and 2296; 2198; 2219, Alclad 2219; 2297 and 2397; 2324; 2519; 2524; 2618 and 2618A; 2624 3xxx Alloy Datasheets 3003, Alclad 3003; 3004, Alclad 3004; 3105 4xxx Alloy Datasheets 4032; 4043 5xxx Alloy Datasheets 5005; 5050; 5052 and 5252; 5056, Alclad 5056; 5083; 5086, Alclad 5086; 5154 and 5154A; 5182; 5254; 5454; 5456; 5457, 5557, and 5657; 5652; 5754 6xxx Alloy Datasheets 6005, 6005A and 6105; 6009 and 6010; 6013; 6022; 6033, 6040, and 6041; 6042; 6056; 6061 Alclad 6061; 6063; 6069; 6082; 6101 and 6201; 6151; 6156; 6262; 6351; 6463 7xxx Alloy Datasheets 7003; 7005; 7020; 7039; 7040 and 7140; 7049 and 7049A; 7050; 7055; 7065; 7072; 7075, Alclad 7075; 7076; 7085; 7097; 7099; 7150; 7175 and 7475; 7255; 7349; 7449; 7475 Cast Aluminum Alloys Properties and Selection of Cast Aluminum Alloys Cast Aluminum Alloy Datasheets 201.0, A201.0; 206.0, A206.0; 208.0; 238.0; 242.0; 295.0; 296.0, 308.0; 319.0, A319.0, B319.0, and 320.0; 332.0; 333.0 and A333.0; 336.0; 354.0; 355.0, C355.0; 356.0, A356.0; 357.0 and Variations A357.0 to F357.0; 359.0; 360.0, A360.0; 362.0; 365.0 and A365.0; 367.0 and 368.0; 380.0, A380.0, and B380.0; 383.0, 384.0, and A384.0; 390.0, A390.0 and B390.0; 391, A391.0 and 8391.0, 413.0, A413.0; 443.0, A443.0, B443.0, C443.0, 511.0, 512.0, and 513.0; 514.0 and 515.0; 518.0; 520.0; 535.0, A535.0, B535.0, 7099 and 7199; 710.0; 711.0 and 712.0; 713.0; 771.0 and 772.0, 850.0, 851.0, 852.0, and 853.0 Appendices Aluminum Alloy Temper Designations and Definitions Aluminum Filler Metal Selection Charts Nominal Compositions and Composition Limits for Wrought Aluminum Alloys Nominal Compositions and Composition Limits for Aluminum Casting Alloys Typical Room Temperature Physical Properties of Wrought Aluminum Alloys

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Book SynopsisExamines more than 100 cases of failure and the process by which they were analyzed, diagnosed, and resolved.Provides expert analysis and insight on a variety of materials, failure modes, root causes, and analytical techniques.Includes sections dedicated to specific components, industries, and other factors, as follows: Transportation and Motive Power Systems – Air and Spacecraft, Automobiles and Trucks, Construction and Farming Equipment, Rail and Rolling Stock, Watercraft Buildings and Bridges – Bridges and Suspensions, Buildings and Building Systems, Building and Construction Materials, Towers and Architectural Structures Petrochemical/Chemical Processing – Pipe and Piping, Pressure Vessels and Boilers, Pulp and Paper Processing, Storage Tanks, Turbomachinery Mining and Manufacturing – Material Handling and Conveying, Thermal Processing Equipment, Oil and Gas, Offshore and Marine Mechanical Components – Bearing Failures, Fastener Failures, Gear Failures, Shaft Failures Failure Modes – Corrosion, Distortion/Deformation, Fracture, Wear Processing Related Failures – Casting Defects, Metalworking Defects, Heat Treating Defects, Welding Defects

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Book SynopsisThis brand new volume in the ASM Handbook series has been developed to address the current and rapidly expanding importance of additive manufacturing (AM). ASM Handbook, Volume 24: Additive Manufacturing Processes provides the latest knowledge in materials, processes, and applications of AM, written by the leading experts in research and industry.It begins with an introduction and history of AM, authored by some of the key participants in that history as they trace the evolution of AM. The complete suite of materials and processes for polymers and ceramics are described in detail in the next two divisions. A division on metal AM processes begins with an in-depth description of the production and characterization of metal powders, which has a big effect on the success or failure of metal AM processes. The book describes AM processing of a wide variety of materials, illustrating differences in characteristics of metal alloys produced by AM processes in contrast to conventional processes. Volume 24 also covers direct-write processes, which take advantage of AM processes to combine materials and devices for multifunctional engineering applications.

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Book SynopsisThe new ASM Handbook, Volume 11: Failure Analysis and Prevention is a valuable resource for failure analysts, engineers, and technical personnel who are looking to identify the root cause(s) of failures and to prevent future failures. The editors and hundreds of authors and peer reviewers worked tirelessly to revise Volume 11 from its 2002 and 1986 editions with the goal to provide the “go-to” reference for those confronted with the failure of a machine or component.Volume 11 contains divisions devoted to the practice of failure analysis, tools and techniques, fatigue and fracture, environmental and corrosion-related failures, wear failures, and distortion. The emphasis is on general principles with the widest applicability to situations that the reader is likely to encounter.For the specific considerations associated with common types of components, the companion ASM Handbook, Volume 11A: Analysis and Prevention of Component and Equipment Failures, is scheduled for publication in 2021.Table of Contents INTRODUCTION TO FAILURE ANALYSIS AND PREVENTION Introduction to Failure Analysis and Prevention PRACTICE OF FAILURE ANALYSIS The Failure Analysis Process: An Overview How to Organize and Run a Failure Investigation Determination and Classification of Damage Examination of Damage and Material Evaluation Nondestructive Evaluation Applications for Failure Analysis Bulk and Microscale Composition Analysis Microfractography and Metallography for Failure Analysis Mechanical Testing Stress Analysis and Fracture Mechanics Finite Element Modeling and Failure Analysis Modeling and Accident Reconstruction Data Review, Conclusions, and Report Preparation TOOLS AND TECHNIQUES IN FAILURE ANALYSIS Visual Examination and Photography in Failure Analysis Nondestructive Testing in Failure Analysis Quantitative Chemical Analysis of Metals Failure Analysis Metallographic Techniques in Failure Analysis X-Ray Diffraction Residual Stress Measurement in Failure Analysis Scanning Electron Microscopy X-ray Spectroscopy in Failure Analysis Chemical Characterization of Surfaces FATIGUE AND FRACTURE Fracture Appearance and Mechanisms of Deformation and Fracture Mechanisms and Appearances of Ductile and Brittle Fracture in Metals Fatigue Fracture Appearances Intergranular Fracture Monotonic Overload and Embrittlement Fatigue Failures Creep and Stress Rupture Failures Thermomechanical Fatigue: Mechanisms and Practical Life Analysis ENVIRONMENTAL AND CORROSION-RELATED FAILURES Analysis and Prevention of Environmental and Corrosion-Related Failures Forms of Corrosion Hydrogen Damage and Embrittlement Stress-Corrosion Cracking Liquid Metal and Solid Metal Induced Embrittlement High-Temperature Corrosion-Related Failures Biological Corrosion Failures WEAR FAILURES Fundamentals of Wear Failures Abrasive Wear Failures Adhesive Wear Failures Fretting Wear Failures Rolling Contact Fatigue Impact Wear Failures Corrosive Wear Failures Erosive Wear Failures Liquid Droplet Impingement Erosion DISTORTION Analysis of Distortion and Deformation REFERENCE INFORMATION Glossary of Terms

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Book SynopsisA resource for failure analysts, engineers, and technical personnel who are looking to identify the root cause(s) of failures and to prevent future failures. Coverage includes engineering aspects of failure and prevention, structural life assessment methods, metal manufacturing aspects of failure, and failure analysis of metallic components.

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Book SynopsisCasting Equipment Engineering Guide is an essential resource covering engineering details of casting equipment, their design features, applications, capabilities, and selection guidelines.This book is written for mechanical engineers, practicing engineers, engineering students, and metallurgists specializing in casting technology.It covers all aspects of shape casting from the flow of raw materials to product inspection and testing. It describes the equipment and procedures used for sand and metal charge storage and handling, sand conditioning, molding and core making, iron and steel melting and pouring, aluminum melting and dosing, aluminum die casting, and gravity and low-pressure permanent and semipermanent molding. It also includes a chapter on post-process cleaning and heat treating and one on plant layout.Additionally, the book provides information on the design and operation of equipment, the calculation of important parameters, and the considerations involved in selecting the right process and equipment to produce iron, steel, and aluminum castings for specific applications.

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Book SynopsisIn the automotive and aerospace industries, the need for strong yet light materials has given rise to extensive research into aluminum and magnesium alloys and formable titanium alloys. All of these are categorized as light weight materials. The distinguishing feature of light weight materials is that they are low density, but they have a wide range of properties and, as a result, a wide range of applications. This book provides researchers and students with an overview of the recent advancements in light weight material processing, manufacturing and characterization. It contains chapters by eminent researchers on topics associated with light weight materials, including on the current buzzword “composite materials”. First, this book describes the current status of light weight materials. Then, it studies applications of these materials, given that, as the densities vary, so do the applications, ranging from automobiles and aviation to bio-mechatronics. This book will therefore serve as an excellent guide to this field.Table of ContentsPreface xi Part 1 Manufacturing Processing Techniques 1 Chapter 1 Additive Manufacturing: Technology, Materials and Applications in Aerospace 3 Veeman DHINAKARAN, Mahesh VARSHA SHREE, Thimmaiah JAGADEESHA and Madabushi SWAPNA SAI 1.1 Introduction 4 1.2 Additive manufacturing configuration 5 1.3 Classification of AM technology 6 1.3.1 Laser beam melting 6 1.3.2 Electron beam melting 7 1.3.3 Selective laser melting 8 1.3.4 Direct metal laser sintering 9 1.3.5 Laser metal fusion 10 1.3.6 Direct metal deposition 11 1.4 Materials used in AM technology 12 1.4.1 Titanium and its alloys 13 1.4.2 Inconel 13 1.4.3 Aluminum 14 1.4.4 Stainless steel 15 1.5 Aerospace applications of additive manufacturing 15 1.6 Challenges faced in the aerospace industry 17 1.7 Overcoming aerospace challenges with AM 17 1.8 Future work 17 1.9 Conclusion 18 1.10 References 18 1.11 Key terms and definitions 21 Chapter 2 Study of the Manufacturing Process of Polymer Spur Gears: A Light Weight Gear Material 23 Jitendra Kumar KATIYAR and Hemalata JENA 2.1 Introduction 23 2.2 Gear manufacturing process 25 2.2.1 Gear hobbing machine 26 2.2.2 Injection molding 27 2.3 Additive manufacturing/rapid prototyping 31 2.4 Laser ablation 32 2.5 Hot embossing 33 2.6 Conclusion 34 2.7 References 35 Chapter 3 Recent Trends in Welding Polymers and Polymer–Metal Hybrid Structures 39 Jinesh Kumar JAIN and Pankaj SONIA 3.1 Introduction 40 3.2 Polymer and composites 41 3.3 Polymerization 42 3.4 Synthesis of polymer composites 45 3.5 Types of fillers in composites 48 3.5.1 Effect of reinforcement orientation 51 3.6 Welding polymers 51 3.7 Introduction of lightweight metal and alloys 53 3.7.1 Magnesium alloys 53 3.7.2 Aluminum alloys 59 3.8 Welding dissimilar metal alloys 61 3.8.1 Friction stir welding 61 3.8.2 Welding polymer and metal alloys 62 3.9 Industrial application of polymers 64 3.10 Conclusion 66 3.11 References 67 Part 2 Characterization 73 Chapter 4 Preparation and Characterization of a Composite Material Using Sisal fibers for Light Body Vehicles 75 Zewdie ALEMAYEHU, Ramesh Babu NALLAMOTHU, Mekonnen LİBEN, Seshu Kishan NALLAMOTHU and Anantha Kamal NALLAMOTHU 4.1 Introduction 76 4.1.1 Statement of the problem 76 4.1.2 General objective 77 4.1.3 Specific objectives 77 4.1.4 Significance of the study 77 4.2 Literature review 78 4.2.1 Introduction 78 4.2.2 Previous works on natural fiber polymer composites 78 4.3 Materials and methods 79 4.3.1 Sample preparation methods 80 4.4 Results and discussion 90 4.4.1 Experimental results 90 4.4.2 Observation 103 4.5 Comparison of previous works 106 4.5.1 Tensile strength 106 4.5.2 Bending strength 106 4.6 Conclusion and recommendation 107 4.6.1 Recommendations for prospective applications 108 4.6.2 Scope for future work 108 4.7 References 109 Chapter 5 Optimizing the Polystyrene Catalytic Cracking Process Using Response Surface Methodology 111 Selvaganapathy THAMBIYAPILLAI, Muthuvelayudham RAMANUJAM and Jayakumar MANI 5.1 Introduction 112 5.2 Material and methods 114 5.2.1 Materials 114 5.2.2 Experimental procedure and characterization 116 5.2.3 Design of catalytic cracking experiment using response surface methodology 118 5.3 Results and discussion 119 5.3.1 Thermal analysis of polystyrene 119 5.3.2 SEM-EDX analysis 120 5.3.3 Model development for catalytic cracking of polystyrene 124 5.3.4 Combined effect of process parameters on the response (Y) 128 5.3.5 Characterization of liquid yield 133 5.3.6 Factors affecting catalytic cracking of polystyrene 136 5.4 Conclusion 139 5.5 References 140 Part 3 Analysis 143 Chapter 6 FEA Comparative Studies on Heat Flux and Thermal Stress Analysis during Conduction Mode and Keyhole Mode in the Laser Beam Welding 145 Harinadh VEMANABOINA, Suresh AKELLA and Ramesh Kumar BUDDU 6.1 Introduction 145 6.2 Heat in laser welding 146 6.3 Modeling 148 6.4 Results and discussion 149 6.4.1 Keyhole model 149 6.4.2 Conduction model 152 6.5 Conclusion 155 6.6 References 156 Chapter 7 Effect of Formability Parameters on Tailor-Welded Blanks of Light Weight Materials 159 Dappu DEEPIKA, Akkireddy Anitha LAKSHMI, Tanya BUDDI and Chalamalasetti Srinivas RAO 7.1 Introduction 159 7.2 Experimental procedure 161 7.3 Results and discussion 169 7.4 Conclusion 189 7.5 References 192 Chapter 8 Design and Analysis of Sedan Car B-pillar Outer Panel Using Abirbara with S-glass Fiber Hybrid Composites 197 Ramesh Babu NALLAMOTHU, Melkamu Yigrem YIHUNIE, Anantha Kamal NALLAMOTHU and Seshu Kishan NALLAMOTHU 8.1 Introduction 198 8.2 Materials and methods 202 8.2.1 Materials 202 8.2.2 Methods 206 8.3 Composite preparation, testing and analysis 207 8.3.1 Composite preparation 207 8.3.2 Testing and analysis 210 8.4 Design analysis of the B-pillar panel 214 8.5 Conclusion 219 8.6 Recommendations 220 8.7 Acknowledgments 220 8.8 References 221 List of Authors 223 Index 227

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Book SynopsisIn recent years, significant developments have been made to increase the mechanical strength of steels in order to reduce the overall weight of structures, particularly in motor vehicles. Depending on the application, the increase in strength should not be at the expense of forming and in-use properties. The development of ultra-high strength steels requires a search for new trade-offs between these properties in order to optimize the final microstructure. New Advanced High Strength Steels analyzes the interactions between tensile mechanical properties and properties such as work hardening, anisotropy, resistance to rupture, fatigue life, corrosion resistance, crashworthiness, edge retention, hydrogen resistance and weldability. It also examines the links between the microstructural parameters of high-strength steels and the properties mentioned above. It highlights the metallurgical developments that have been necessary for the emergence of these new generations of steels. The book concludes with a look ahead to future developments in ultra-high strength steels.Table of ContentsForeword xiiiDavid EMBURY Introduction xviiMohamed GOUNÉ, Thierry IUNG and Jean-Hubert SCHMITT Chapter 1 Strain Hardening and Tensile Properties 1Mohamed GOUNÉ and Olivier BOUAZIZ 1.1 Introductory remarks 1 1.2 Stress/strain curve: macroscopic quantities 2 1.3 Behavior of a single-phase structure: microscopic approach 3 1.4 Strain hardening and mechanical behavior of precipitation hardened micro-alloyed steels 7 1.5 Strain hardening and mechanical behavior of martensitic steels 19 1.6 Austenitic steels Fe-0.6C-22Mn with TWIP effect 23 1.7 Multiphase quenching and partitioning steels 28 1.8 Conclusion 38 1.9 References 39 Chapter 2 Anisotropy and Mechanical Properties 43Hélène RÉGLÉ and Brigitte BACROIX 2.1 Challenges 44 2.2 Textural anisotropy and mechanical properties 46 2.3 Conclusion 61 2.4 Calculation details 62 2.5 References 67 Chapter 3 Compromise between Strength and Fracture Resistance 71Anne-Françoise GOURGUES-LORENZON and Thierry IUNG 3.1 Introduction 71 3.2 Methods for measuring the resistance to damage and fracture 71 3.3 Physical mechanisms and microstructural control of damage and fracture 80 3.4 Examples of application 89 3.5 Conclusion and outlook 99 3.6 References 100 Chapter 4 Compromise between Tensile and Fatigue Strength 103Véronique FAVIER, André GALTIER, Rémi MUNIER and Bastien WEBER 4.1 Toughness: the main cause of part failure in service 103 4.2 Fatigue: from crack initiation to failure 104 4.3 How to improve fatigue life through metallurgy? 112 4.4 Increasing role of defects in high strength steels 123 4.5 Specific treatments for fatigue performance 126 4.6 Conclusion 128 4.7 References 129 Chapter 5 High Strength Steels and Coatings 133Marie-Laurence GIORGI and Jean-Michel MATAIGNE 5.1 Introduction 133 5.2 The continuous galvanizing process 134 5.3 Selective oxidation during continuous annealing 143 5.4 Coatings on high-strength steels 149 5.5 Conclusion 160 5.6 References 161 Chapter 6 Corrosion Resistant Steels with High Mechanical Properties 167Franck TANCRET, Christine BLANC and Vincent VIGNAL 6.1 Introduction 167 6.2 General principles of corrosion/oxidation and corrosion/oxidation resistance 168 6.3 Wet corrosion resistant and high strength steels 169 6.4 Alloys resistant to hot oxidation and creep 184 6.5 Conclusion 193 6.6 References 194 Chapter 7 Crashworthiness by Steels 197Dominique CORNETTE, Pascal DIETSCH, Kevin TIHAY and Sébastien ALLAIN 7.1 Introduction and industrial issues 197 7.2 The tests in force, or how to pass from the behavior of the complete vehicle to the behavior of the material 198 7.3 Parameters influencing the material during the manufacturing process and the behavior in service 214 7.4 Adequacy between material properties and crash behavior according to the different evaluation criteria 220 7.5 Conclusion 230 7.6 References 230 Chapter 8 Cut Edge Behavior 233Stéphane GODET, Ève-Line CADOTTE and Astrid PERLADE 8.1 Introduction/problem analysis 233 8.2 Cutting processes and characteristics of the cut edge 234 8.3 Behavior of the cut edge 240 8.4 Conclusion 260 8.5 References 260 Chapter 9 The Relationship between Mechanical Strength and Hydrogen Embrittlement 263Xavier FEAUGAS and Colin SCOTT 9.1 Introduction 263 9.2 How to identify and characterize HE 264 9.3 Solubility and (apparent) diffusion coefficients of hydrogen in steels 268 9.4 Case study: embrittlement of fastener steels 276 9.5 Case study: HE of thin sheets 284 9.6 Research and perspectives 293 9.7 References 295 Chapter 10 Weldability of High Strength Steels 303Thomas DUPUY, Jessy HAOUAS and Laurent JUBIN 10.1 Introduction 303 10.2 Weldability issues 307 10.3 Solutions for a good weldability of high-strength steels 324 10.4 References 330 Appendix: A Brief Review of Steel Metallurgy 333Thierry IUNG and Jean-Hubert SCHMITT Postface: What's Next for Ultra-high Strength Steels? 373François MUDRY List of Authors 381 Index 385

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Book SynopsisThis title provides the fundamental bases for developing turbulence models on rational grounds. The main different methods of approach are considered, ranging from statistical modelling at various degrees of complexity to numerical simulations of turbulence. Each of these various methods has its own specific performances and limitations, which appear to be complementary rather than competitive. After a discussion of the basic concepts, mathematical tools and methods for closure, the book considers second order closure models. Emphasis is placed upon this approach because it embodies potentials for clarifying numerous problems in turbulent shear flows. Simpler, generally older models are then presented as simplified versions of the more general second order models. The influence of extra physical parameters is also considered. Finally, the book concludes by examining large Eddy numerical simulations methods. Given the book’s comprehensive coverage, those involved in the theoretical or practical study of turbulence problems in fluids will find this a useful and informative read.Table of ContentsChapter 1. Fundamentals of statistical modelling: basic physical concepts. Chapter 2. Turbulence transport equations for an incompressible fluid. Chapter 3. Mathematical tools. Chapter 4. Methodology for one point closures. Chapter 5. Homogenous anisotropic turbulence. Chapter 6. Modelling of the Reynolds stress evolution equations. Chapter 7. Turbulence scales. Chapter 8. Advanced closures: new directions in second order modeling. Chapter 9. Modeling the turbulent flux evolution equations for a passive scalar. Chapter 10. The passive scalar variance and its dissipation rate. Chapter 11. Simplified closures: two and three transport equation models. Chapter 12. Simplified closures: zero and one transport equation models. Chapter 13. Treatment of low Reynolds number turbulence. Chapter 14. Wall treatment: methods and problems. Chapter 15. Influence of Archimedean forces. Chapter 16. Notes on the problems posed by the study of complex flows. Chapter 17. Variable density turbulent flows. Chapter 18. Multiple scale models. Chapter 19. Large Eddy simulations. Chapter 20. Synopsis on numerical methods.

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Book SynopsisSound is produced by vibrations and as such can be dampened or augmented based on materials selection. This title looks at the effects of sound and vibration on thin structures and details how damage may be avoided, acoustical effects created, and sound levels controlled.Table of ContentsPreface 11 1 Equations Governing the Vibrations of Thin Structures 15 1.1 Introduction 15 1.1.1 General Considerations on Thin Structures 15 1.1.2 Overview of the Energy Method 16 1.2 Thin Plates 17 1.2.1 Plate with Constant Thickness 18 1.2.2 Plate with Variable Thickness 25 1.2.3 Boundary with an Angular Point 27 1.3 Beams 29 1.4 Circular Cylindrical Shells 31 1.5 Spherical Shells 38 1.5.1 Approximation of the Strain and Stress Tensors and Application of the Virtual Works Theorem 39 1.5.2 Regularity Conditions at the Apexes 46 1.6 Variational Form of the Equations Governing Harmonic Vibrations of Plates and Shells 49 1.6.1 Variational Form of the Plate Equation 50 1.6.2 Variational Form of the Shells Equations 51 1.7 Exercises 52 2 Vibratory Response of Thin Structures in vacuo: Resonance Modes, Forced Harmonic Regime, Transient Regime 53 2.1 Introduction 53 2.2 Vibrations of Constant Cross-Section Beams 55 2.2.1 Independent Solutions for the Homogenous Beam Equation 55 2.2.2 Response of an Infinite Beam to a Point Harmonic Force 57 2.2.3 Resonance Modes of Finite Length Beams 59 2.2.4 Response of a Finite Length Beam to a Harmonic Force 66 2.3 Vibrations of Plates 68 2.3.1 Free Vibrations of an Infinite Plate 68 2.3.2 Green’s Kernel and Green’s function for the Time Harmonic Plate Equation and Response of an Infinite Plate to a Harmonic Excitation 71 2.3.3 Harmonic Vibrations of a Plate of Finite Dimensions: General Definition and Theorems 73 2.3.4 Resonance Modes and Resonance Frequencies of Circular Plates with Uniform Boundary Conditions 76 2.3.5 Resonance Modes and Resonance Frequencies of Rectangular Plates with Uniform Boundary Conditions 84 2.3.6 Response of a Plate to a Harmonic Excitation: Resonance Modes Series Representation 97 2.3.7 Boundary Integral Equations and the Boundary Element Method 99 2.3.8 Resonance Frequencies of Plates with Variable Thickness 117 2.3.9 Transient Response of an Infinite Plate with Constant Thickness 119 2.4 Vibrations of Cylindrical Shells 122 2.4.1 Free Oscillations of Cylindrical Shells of Infinite Length 122 2.4.2 Green’s Tensor for the Cylindrical Shell Equation 126 2.4.3 Harmonic Vibrations of a Cylindrical Shell of Finite Dimensions: General Definition and Theorems 129 2.4.4 Resonance Modes of a Cylindrical Shell Closed by Shear Diaphragms at Both Ends 130 2.4.5 Resonance Modes of a Cylindrical Shell Clamped at Both Ends 133 2.4.6 Response of a Cylindrical Shell to a Harmonic Excitation: Resonance Modes Representation 137 2.4.7 Boundary Integral Equations and Boundary Element Method 138 2.5 Vibrations of Spherical Shells 141 2.5.1 General Definition and Theorems 141 2.5.2 Solution of the Time Harmonic Spherical Shell Equation 143 2.6 Exercises 145 3 Acoustic Radiation and Transmission by Thin Structures 149 3.1 Introduction 149 3.2 Sound Transmission Across a Piston in a One-Dimensional Waveguide 151 3.2.1 Governing Equations 151 3.2.2 Time Fourier Transform of the Equations – Response of the System to a Harmonic Excitation 153 3.2.3 Response of the System to a Transient Excitation of the Piston 159 3.3 A One-dimensional Example of a Cavity Closed by a Vibrating Boundary 160 3.3.1 Equations Governing Free Harmonic Oscillations and their Reduced Form 161 3.3.2 Transmission of Sound Across the Vibrating Boundary 165 3.4 A Little Acoustics 168 3.4.1 Variational Form of the Wave Equation and of the Helmholtz Equation 168 3.4.2 Free-field Green’s Function of the Helmholtz Equation 170 3.4.3 Series Expansions of the Free Field Green’s Function of the Helmholtz Equation 170 3.4.4 Green’s Formula for the Helmholtz Operator and Green’s Representation of the Solution of the Helmholtz Equation 172 3.4.5 Numerical Difficulties 175 3.5 Infinite Structures 176 3.5.1 Infinite Plate in Contact with a Single Fluid or Two Different Fluids 176 3.5.2 Free Oscillations of an Infinite Circular Cylindrical Shell Filled with a vacuum and Immersed in a Fluid of Infinite Extent 196 3.5.3 A Few Remarks on the Free Oscillations of an Infinite Circular Cylindrical Shell containing a Fluid and Immersed in a Second Fluid of Infinite Extent 202 3.6 Baffled Rectangular Plate 203 3.6.1 General Theory: Eigenmodes, Resonance Modes, Series Expansion of the Response of the System 203 3.6.2 Rectangular Plate Clamped along its Boundary: Numerical Approximation of the Resonance Modes 209 3.6.3 Application: Transient Response of a Plate Struck by a Hammer 222 3.7 General Method for the Harmonic Regime: Classical Variational Formulation and Green’s Representation of the Plate Displacement 224 3.8 Baffled Plate Closing a Cavity 228 3.8.1 Equations Governing the Harmonic Motion of the Plate-Cavity-External Fluid System 229 3.8.2 Integro-differential Equation for the Plate Displacement and Matched Asymptotic Expansions 232 3.8.3 Boundary Integral Representation of the Interior Acoustic Pressure 237 3.8.4 Comparison between Numerical Predictions and Experiments 238 3.9 Cylindrical Finite Length Baffled Shell Excited by a Turbulent Internal Flow 243 3.9.1 Basic Equations and Green’s Representations of the Exterior and Interior Acoustic Pressures for a Normal Point Force 245 3.9.2 Numerical Methods for Solving Equations (3.111) 246 3.9.3 Comparison Between Numerical Results and Experimental Data 248 3.10 Radiation by a Finite Length Cylindrical Shell Excited by an Internal Acoustic Source 251 3.10.1 Statement of the Problem 251 3.10.2 Boundary Integral Representations of the Radiated Pressure and of the Shell Displacement 253 3.10.3 Green’s Representation of the Interior Acoustic Pressure and Matched Asymptotic Expansions 256 3.10.4 Directivity Pattern of the Radiated Acoustic Pressure 260 3.10.5 Numerical Method, Results and Concluding Remarks 262 3.11 Diffraction of a Transient Acoustic Wave by a Line 2’ Shell 264 3.11.1 Statement of the Problem 266 3.11.2 Resonance Modes and Response of the System to an Incident Transient Acoustic Wave 272 3.11.3 Numerical Method and Comparison between Numerical Prediction and Experimental Results 274 3.12 Exercises 278 Bibliography 279 Notations 285 Index 287

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Book SynopsisAccompanying the present trend of engineering systems aimed at size reduction and design at microscopic/nanoscopic length scales, Mechanics of Dislocation Fields describes the self-organization of dislocation ensembles at small length scales and its consequences on the overall mechanical behavior of crystalline bodies. The account of the fundamental interactions between the dislocations and other microscopic crystal defects is based on the use of smooth field quantities and powerful tools from the mathematical theory of partial differential equations. The resulting theory is able to describe the emergence of dislocation microstructures and their evolution along complex loading paths. Scale transitions are performed between the properties of the dislocation ensembles and the mechanical behavior of the body. Several variants of this overall scheme are examined which focus on dislocation cores, electromechanical interactions of dislocations with electric charges in dielectric materials, the intermittency and scale-invariance of dislocation activity, grain-to-grain interactions in polycrystals, size effects on mechanical behavior and path dependence of strain hardening.Table of ContentsAcknowledgements ix Introduction xi Chapter 1 Continuous Dislocation Modeling 1 1.1 Introduction 1 1.2 Lattice incompatibility 2 1.3 Burgers vector 5 1.4 Compatibility conditions 8 1.5 Dislocation fields 10 1.6 Tangential continuity at interfaces 13 1.7 Curvatures and rotational incompatibiliy 19 1.8 Incompatibility tensor 22 1.9 Conclusion 23 1.10 Problems 23 1.10.1 Discrete versus continuous modeling of crystal defects 23 1.10.2 Incompatibility in simple shear 25 1.10.3 Frank’s relation 26 1.11 Solutions 27 1.11.1 Discrete versus continuous modeling of crystal defects 27 1.11.2 Incompatibility in simple shear 28 1.11.3 Frank’s relation 29 Chapter 2 Elasto-static Field Equations 31 2.1 Introduction 31 2.2 Elasto-static solution to field equations 31 2.2.1 Stokes-Helmholtz decomposition and Poisson-type equations 32 2.2.2 Navier-type equations for compatible elastic distortion fields 34 2.3 Straight screw dislocation in a linear isotropic elastic medium 35 2.4 Straight edge dislocation in a linear isotropic elastic medium 37 2.5 Conclusion 38 2.6 Problems 39 2.6.1 Screw dislocation 39 2.6.2 Twist boundary 39 2.6.3 Tilt boundary 41 2.6.4 Zero-stress everywhere dislocation fields 41 2.7 Solutions 42 2.7.1 Screw dislocation 42 2.7.2 Twist boundary 43 2.7.3 Tilt boundary 45 2.7.4 Zero-stress everywhere dislocation fields 46 Chapter 3 Dislocation Transport 49 3.1 Introduction 49 3.2 Dislocation flux and plastic distortion rate 50 3.3 Coarse graining 52 3.4 Compatibility versus incompatibility of plasticity 54 3.5 Tangential continuity of plastic distortion rate 57 3.6 Transport equations 60 3.6.1 Small transformations 60 3.6.2 Finite transformations 62 3.7 Transport waves 64 3.7.1 Annihilation 66 3.7.2 Expansion of dislocation loops 68 3.7.3 Initiation of a Frank–Read source 69 3.8 Numerical algorithms for dislocation transport 71 3.9 Conclusion 76 3.10 Problems 76 3.10.1 Propagation of a discontinuous dislocation density 76 3.10.2 Dislocation loop expansion 78 3.10.3 Stability / instability of homogeneous dislocation distributions 79 3.10.4 Dislocation nucleation 80 3.11 Solutions 81 3.11.1 Propagation of a discontinuous dislocation density 81 3.11.2 Expansion of dislocation loops 84 3.11.3 Stability / instability of homogeneous dislocation distributions 85 3.11.4 Dislocation nucleation 86 Chapter 4 Constitutive Relations 89 4.1 Introduction 89 4.2 Dissipation 90 4.3 Pressure independence 92 4.4 Dislocation climb versus dislocation glide 93 4.5 Viscoplastic relationships 94 4.6 Coarse graining 96 4.7 Contact with conventional crystal plasticity 97 Chapter 5 Elasto-plastic Field Equations 99 5.1 Introduction 99 5.2 Fundamental field equations 99 5.3 Boundary conditions 101 5.4 Coarse graining 102 5.5 Resolution algorithm 104 5.6 Reduced field equations 105 5.6.1 Plane dislocations 107 5.7 Augmented crystal plasticity 109 5.8 Dynamics of a twist boundary 111 5.9 Conclusion 116 5.10 Problems 117 5.10.1 Helical dislocations 117 5.11 Solutions 118 5.11.1 Helical dislocations 118 Chapter 6 Case Studies 121 6.1 Introduction 121 6.2 Dislocation core structure 123 6.3 Piezoelectricity and dislocations 132 6.3.1 Coupling piezoelectricity, lattice incompatibility and transport 132 6.3.2 Piezoelectric polarization and dislocations in GaN layers 134 6.3.3 Dislocation transport and electric displacement in GaN layers 137 6.4 Intermittent plasticity 139 6.5 Effects of size on mechanical response 150 6.6 Complex loading paths 159 6.7 Strain localization 170 6.7.1 Experimental data in Al–Cu–Li alloys 171 6.7.2 Simulation results 174 Chapter 7 Review and Conclusions 181 7.1 Comparisons with conventional crystal plasticity 181 7.2 Alternative approaches 183 7.2.1 Peierls-Nabarro model 183 7.2.2 Atomistic simulations 184 7.2.3 Phase field methods 186 7.2.4 Discrete dislocation dynamics 187 7.3 Shortcomings and extensions 190 7.3.1 Fracture and disconnections 190 7.3.2 Rotational incompatibility and disclinations 191 7.3.3 Phase transformation and generalized disclinations 193 7.4 Final remarks 196 Appendix 197 Bibliography 203 Index 217

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Book SynopsisUsing plant material as raw materials for construction is a relatively recent and original topic of research. This book presents an overview of the current knowledge on the material properties and environmental impact of construction materials made from plant particles, which are renewable, recyclable and easily available. It focuses on particles and as well on fibers issued from hemp plant, as well as discussing hemp concretes. The book begins by setting the environmental, economic and social context of agro-concretes, before discussing the nature of plant-based aggregates and binders. The formulation, implementation and mechanical behavior of such building materials are the subject of the following chapters. The focus is then put upon the hygrothermal behavior and acoustical properties of hempcrete, followed by the use of plant-based concretes in structures. The book concludes with the study of life-cycle analysis (LCA) of the environmental characteristics of a banked hempcrete wall on a wooden skeleton. Contents 1. Environmental, Economic and Social Context of Agro-Concretes, Vincent Nozahic and Sofiane Amziane. 2. Characterization of Plant-Based Aggregates. Vincent Picandet. 3. Binders, Gilles Escadeillas, Camille Magniont, Sofiane Amziane and Vincent Nozahic. 4. Formulation and Implementation, Christophe Lanos, Florence Collet, Gérard Lenain and Yves Hustache. 5. Mechanical Behavior, Laurent Arnaud, Sofiane Amziane, Vincent Nozahic and Etienne Gourlay. 6. Hygrothermal Behavior of Hempcrete, Laurent Arnaud, Driss Samri and Étienne Gourlay. 7. Acoustical Properties of Hemp Concretes, Philippe Glé, Emmanuel Gourdon and Laurent Arnaud. 8. Plant-Based Concretes in Structures: Structural Aspect – Addition of a Wooden Support to Absorb the Strain, Philippe Munoz and Didier Pipet. 9. Examination of the Environmental Characteristics of a Banked Hempcrete Wall on a Wooden Skeleton, by Lifecycle Analysis: Feedback on the LCA Experiment from 2005, Marie-Pierre Boutin and Cyril Flamin. About the Authors Sofiane Amziane is Professor and head of the Civil Engineering department at POLYTECH Clermont-Ferrand in France. He is also in charge of the research program dealing with bio-based building materials at Blaise Pascal University (Institut Pascal, Clermont Ferrand, France). He is the secretary of the RILEM Technical Committee 236-BBM dealing with bio-based building materials and the author or co-author of over one hundred papers in scientific journals such as Cement and Concrete Research, Composite Structures or Construction Building Materials as well as international conferences. Laurent Arnaud is a Bridges, Waters and Forestry Engineer (Ingénieur des Ponts, Eaux et Forêts) and researcher at Joseph Fourier University in Grenoble, France. He is also Professor at ENTPE (Ecole Nationale des Travaux Publics de l’Etat). Trained in the field of mechanical engineering, his research has been directed toward the characterization and development of new materials for civil engineering and construction. He is head of the international committee at RILEM – BBM, as well as the author of more than one hundred publications, and holder of an international invention patent.Table of ContentsForeword xi Chapter 1. Environmental, Economic and Social Context of Agro-Concretes 1 Vincent NOZAHIC and Sofiane AMZIANE 1.1. Sustainable development, construction and materials 1 1.1.1. Environmental impacts of the construction sector 2 1.2. Standardization and regulation: toward a global approach 3 1.2.1. Standardization and regulation in force 3 1.2.2. Limitations of the normative and regulatory framework 5 1.3. The materials: an increasingly crucial element 7 1.3.1. Role of the materials in energy consumption 7 1.3.2. What is a low-environmental-impact material? 7 1.3.3. Constantly-changing regulations 8 1.4. The specific case of concretes made from lignocellular particles 9 1.4.1. Development of agro-concretes in the context of France 10 1.5. What does the term “Agro-concrete” mean? 13 1.5.1. General definition 13 1.5.2. Lignocellular resources 13 1.5.3. General characteristics of lignocellular agro-resources 15 1.6. Conclusions 19 1.7. Bibliography 19 Chapter 2. Characterization of Plant-Based Aggregates 27 Vincent PICANDET 2.1. Microstructure of the shiv particles 28 2.1.1. Structure of the stem of fibrous plants 28 2.1.2. SEM observation of hemp shiv particles 30 2.1.3. Chemistry of the cell walls 31 2.1.4. Density and porosity, in the case of hemp shiv 35 2.2. Particle Size Distribution (PSD) 36 2.2.1. General characteristics of aggregates made from fibrous plants 36 2.2.2. Fiber content 37 2.2.3. Methods for characterizing the PSD 38 2.2.4. PSD analyses 48 2.2.5. Comparison of the results obtained by image analysis 52 2.2.6. Characterization of the geometry of the particles 57 2.2.7. Characterization of the PSD 58 2.2.8. Conclusions 65 2.3. Compactness and compressibility 66 2.4. Water absorption capacity 68 2.5. Bibliography 69 Chapter 3. Binders 75 Gilles ESCADEILLAS, Camille MAGNIONT, Sofiane AMZIANE and Vincent NOZAHIC 3.1. Portland cements 75 3.1.1. General 75 3.1.2. Production 76 3.1.3. Chemical and mineral composition 77 3.1.4. Properties 77 3.1.5. Environmental impacts 84 3.2. Lime 84 3.2.1. General 84 3.2.2. Aerial lime 86 3.2.3. Natural hydraulic limes 89 3.3. Lime-pozzolan mixtures 92 3.3.1. Natural pozzolans 93 3.3.2. Calcined natural pozzolans: metakaolin 96 3.3.3. Fly ash 101 3.3.4. Blast furnace slag 103 3.4. Plaster 106 3.4.1. General 106 3.4.2. Production 106 3.4.3. Chemical and mineralogical composition 108 3.4.4. Properties 108 3.4.5. Environmental impacts 110 3.5. Summary 110 3.6. Bibliography 111 Chapter 4. Formulation and Implementation 117 Christophe LANOS, Florence COLLET, Gérard LENAIN and Yves HUSTACHE 4.1. Objectives 117 4.1.1. Preamble 117 4.1.2. Traditional applications 119 4.1.3. Constituents and mixture 120 4.1.4. Methods of implementation 121 4.2. Rules of formulation 122 4.2.1. Basis of usual formulations 122 4.2.2. Influence of the proportion of paste in the mixture 124 4.2.3. Quality of the paste and water content 128 4.2.4. Homogeneity of the paste 135 4.2.5. The relationship between formulation and strength 137 4.2.6. The relationship between formulation and thermo-hydric properties 141 4.3. Examples of formulations 141 4.3.1. Origin of the data 141 4.3.2. Walling application 141 4.3.3. Flooring application 142 4.3.4. Roofing application 142 4.3.5. Other applications 142 4.4. Installation techniques 143 4.4.1. Building a wall using formwork 143 4.4.2. Application by spraying 143 4.4.3. Laying of a floor 144 4.4.4. Creating a roof 144 4.4.5. Other uses 145 4.5. Professional rules for buildings using hempcrete and hemp mortars 145 4.5.1. History 145 4.5.2. Principles and content of the professional regulations 146 4.6. Bibliography 152 Chapter 5. Mechanical Behavior 153 Laurent ARNAUD, Sofiane AMZIANE, Vincent NOZAHIC and Etienne GOURLAY 5.1. Composite material 153 5.1.1. Making of the test tubes 154 5.1.2. Mechanical behavior 154 5.1.3. Effect of initial compression 157 5.1.4. Effect of the nature of the binder 159 5.1.5. Influence of the binder content 162 5.1.6. Influence of the particle size 164 5.1.7. Influence of the curing conditions 165 5.1.8. Evolution over time 166 5.1.9. Interaction between particles and binder 167 5.1.10. Anisotropic behavior 170 5.2. Modeling of the mechanical behavior 171 5.2.1. Empirical approach 171 5.2.2. Self-consistent homogenization approach 173 5.3. Toward the study of a stratified composite 174 5.4. Conclusion 175 5.5. Bibliography 176 Chapter 6. Hygrothermal Behavior of Hempcrete 179 Laurent ARNAUD, Driss SAMRI and Étienne GOURLAY 6.1. Introduction 179 6.2. Heat conductivity 180 6.2.1. Measurement of the conductivity 181 6.2.2. Modeling of the heat conductivity in dry and humid conditions 182 6.2.3. Heat transfers 185 6.3. Hygrothermal transfers 186 6.3.1. Experimental device 186 6.3.2. Stresses 189 6.3.3. Phase changes 191 6.3.4. Hygrothermal transfers 194 6.3.5. Role of coating products applied to hempcrete 196 6.3.6. Conclusions 200 6.4. Thermal characterization of various construction materials 201 6.4.1. Autoclaved aerated concrete 202 6.4.2. Vertically perforated brick 204 6.4.3. Hempcrete 205 6.4.4. Conclusions 210 6.5. Modeling of coupled heat- and mass transfers 211 6.5.1. Introduction 211 6.5.2. Transfer laws 212 6.5.3. Transfer model: the Künzel model 216 6.5.4. Determination of the transfer coefficients 217 6.5.5. Numerical modeling 222 6.6. Conclusions 235 6.7. Bibliography 238 Chapter 7. Acoustical Properties of Hemp Concretes 243 Philippe GLÉ, Emmanuel GOURDON and Laurent ARNAUD 7.1. Introduction 243 7.2. Acoustical properties of the material on the basis of the main mechanisms 244 7.2.1. Influence of the components 244 7.2.2. Influence of the casting method 249 7.3. Modeling the acoustical properties 252 7.3.1. Physical analysis of the acoustical properties being measured 253 7.3.2. The adapted double porosity model and its parameters 255 7.3.3. Experimental validation of the model 257 7.4. Application of the model to the acoustical characterization of shiv 258 7.4.1. Porosity of shiv 258 7.4.2. Resistivity 262 7.5. Conclusion 264 7.6. Bibliography 264 Chapter 8. Plant-Based Concretes in Structures: Structural Aspect – Addition of a Wooden Support to Absorb the Strain 267 Philippe MUNOZ and Didier PIPET 8.1. Introduction 267 8.2. Preliminary test 269 8.2.1. Description of the panel 269 8.2.2. Putting the panel in place on the bracing bank 270 8.2.3. Longitudinal loading and measurement of the movements 271 8.2.4. Behavior of the test bank 273 8.2.5. Behavior of the wooden panel 274 8.3. Test on a composite panel of a wooden skeleton and hempcrete 276 8.3.1. Description of the panel 276 8.3.2. Emplacement of the panel on the bracing bank 276 8.3.3. Vertical loading 279 8.3.4. Longitudinal loading and measurement of the movements 280 8.3.5. Running of the test 281 8.3.6. Feature of the ruin of the panel 283 8.4. Results and comparative analysis 285 8.5. Conclusions and reflections 287 8.6. Acknowledgements 288 8.7. Bibliography 288 Chapter 9. Examination of the Environmental Characteristics of a Banked Hempcrete Wall on a Wooden Skeleton, by Lifecycle Analysis: Feedback on the LCA Experiment from 2005 289 Marie-Pierre BOUTIN and Cyril FLAMIN 9.1. Introduction 289 9.2. Description of the products studied 291 9.3. Method for environmental evaluation of bio-sourced materials 292 9.4. Lifecycle Analysis on hempcrete – methodology, working hypotheses and results 294 9.4.1. Delimitation of the system under study 294 9.4.2. Inventory analysis 298 9.4.3. Impact evaluation 303 9.4.4. Results and interpretation of the lifecycle 305 9.5. Interpretations of the lifecycle, conclusions and reflections 306 9.6. Bibliography 310 List of Authors 313 Index 315

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Book SynopsisIs there a fatigue limit in metals? This question is the main focus of this book. Written by a leading researcher in the field, Claude Bathias presents a thorough and authoritative examination of the coupling between plasticity, crack initiation and heat dissipation for lifetimes that exceed the billion cycle, leading us to question the concept of the fatigue limit, both theoretically and technologically. This is a follow-up to the Fatigue of Materials and Structures series of books previously published in 2011. Contents 1. Introduction on Very High Cycle Fatigue. 2. Plasticity and Initiation in Gigacycle Fatigue. 3. Heating Dissipation in the Gigacycle Regime. About the Authors Claude Bathias is Emeritus Professor at the University of Paris 10-La Defense in France. He started his career as a research engineer in the aerospace and military industry where he remained for 20 years before becoming director of the CNRS laboratory ERA 914 at the University of Compiègne in France. He has launched two international conferences about fatigue: International Conference on the Fatigue of Composite Materials (ICFC) and Very High Cycle Fatigue (VHCF). This new, up-to-date text supplements the book Fatigue of Materials and Structures, which had been previously published by ISTE and John Wiley in 2011. A thorough review of coupling between plasticity, crack priming, and thermal dissipation for lifespans higher than a billion of cycle has led us to question the concept of fatigue limit, from both the theoretical and technological point of view. This book will address that and more.Table of ContentsACKNOWLEDGEMENTS vii CHAPTER 1. INTRODUCTION ON VERY HIGH CYCLE FATIGUE 1 1.1. Fatigue limit, endurance limit and fatigue strength 1 1.2. Absence of an asymptote on the SN curve 5 1.3. Initiation and propagation 6 1.4. Fatigue limit or fatigue strength 7 1.5. SN curves up to 109 cycles 8 1.6. Deterministic prediction of the gigacycle fatigue strength 10 1.7. Gigacycle fatigue of alloys without flaws 12 1.8. Initiation mechanisms at 109 cycles 13 1.9. Conclusion 13 1.10. Bibliography 14 CHAPTER 2. PLASTICITY AND INITIATION IN GIGACYCLE FATIGUE 17 2.1. Evolution of the initiation site from LCF to GCF 17 2.2. Fish-eye growth 20 2.2.1. Fracture surface analysis 20 2.2.2. Plasticity in the GCF regime 23 2.3. Stresses and crack tip intensity factors around spherical and cylindrical voids and inclusions 29 2.3.1. Spherical cavities and inclusions 29 2.3.2. Spherical inclusion 31 2.3.3. Mismatched inclusion larger than the spherical cavity it occupies 31 2.3.4. Cylindrical cavities and inclusions 33 2.3.5. Cracking from a hemispherical surface void 35 2.3.6. Crack tip stress intensity factors for cylindrical inclusions with misfit in both size and material properties 38 2.4. Estimation of the fish-eye formation from the Paris–Hertzberg law 42 2.4.1. “Short crack” number of cycles 47 2.4.2. “Long crack” number of cycles 48 2.4.3. “Below threshold” number of cycles 48 2.5. Example of fish-eye formation in a bearing steel 49 2.6. Fish-eye formation at the microscopic level 52 2.6.1. Dark area observations 53 2.6.2. “Penny-shaped area” observations 54 2.6.3. Fracture surface with large radial ridges 56 2.6.4. Identification of the models 59 2.6.5. Conclusion 62 2.7. Instability of microstructure in very high cycle fatigue (VHCF) 62 2.8. Industrial practical case: damage tolerance at 109 cycles 69 2.8.1. Fatigue threshold in N18 70 2.8.2. Fatigue crack initiation of N18 alloy 71 2.8.3. Mechanisms of the GCF of N18 alloy 73 2.9. Bibliography 74 CHAPTER 3. HEATING DISSIPATION IN THE GIGACYCLE REGIME 77 3.1. Temperature increase at 20 kHz 77 3.2. Detection of fish-eye formation 81 3.3. Experimental verification of Nf by thermal dissipation 83 3.4. Relation between thermal energy and cyclic plastic energy 85 3.5. Effect of metallurgical instability at the yield point in ultrasonic fatigue 89 3.6. Gigacycle fatigue of pure metals 91 3.6.1. Microplasticity in the ferrite 95 3.6.2. Effect of gigacycle fatigue loading on the yield stress in Armco iron 97 3.6.3. Temperature measurement on Armco iron 98 3.6.4. Intrinsic thermal dissipation in Armco iron 102 3.6.5. Analysis of surface fatigue crack on iron 105 3.7. Conclusion 109 3.8. Bibliography 110 INDEX 113

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Book SynopsisCapillary phenomena occur in both natural and human-made systems, from equilibria in the presence of solids (grains, walls, metal wires) to multiphase flows in heterogeneous and fractured porous media. This book, composed of two volumes, develops fluid mechanics approaches for two immiscible fluids (water/air or water/oil) in the presence of solids (tubes, joints, grains, porous media). Their hydrodynamics are typically dominated by capillarity and viscous dissipation. This first volume presents the basic concepts and investigates two-phase equilibria, before analyzing two-phase hydrodynamics in discrete and/or statistical systems (tubular pores, planar joints). It then studies flows in heterogeneous and stratified porous media, such as soils and rocks, based on Darcy’s law. This analysis includes unsaturated flow (Richards equation) and two-phase flow (Muskat equations). Overall, the two volumes contain basic physical concepts, theoretical analyses, field investigations and statistical and numerical approaches to capillary-driven equilibria and flows in heterogeneous systemsTable of Contents1. Fluids, Porous Media and REV: Basic Concepts. 2. Two-Phase Physics: Surface Tension, Interfaces, Capillary Liquid / Vapor Equilibria. 3. Capillary Equilibria in Pores, Tubes and Joints. 4. Pore-Scale Capillary Flows (Tubes, Joints). 5. Darcy-Scale Capillary Flows in Heterogeneous or Statistical Continua (Richards and Muskat).

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Book SynopsisTexturing surfaces at micro- and/or nano-scales modifies the interactions of liquids and solids. This book is a summary of the state of the art concerning the development and use of micro/nano-technologies for the design of synthetic liquid repellent surfaces with a particular focus on super-omniphobic materials. It proposes a comprehensive understanding of the physical mechanisms involved in the wetting of these surfaces and reviews emerging applications in various fields such as energy harvesting and biology, as well as highlighting the current limitations and challenges which are yet to be overcome.Table of Contents1. Nanotechnologies for Synthetic Super 
Non-wetting Surfaces. 2. Wetting on Heterogeneous Surfaces. 3. Engineering Super Non-wetting Materials. 4. Fabrication of Synthetic Super
Non-wetting Surfaces. 5. Characterization Techniques for Super 
Non-wetting Surfaces. 6. Emerging Applications.

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Book SynopsisThis book focuses on a particular class of models (namely Multi-Mechanism models) and their applications to extensive experimental data base related to different kind of materials. These models (i) are able to describe the main mechanical effects in plasticity, creep, creep/plasticity interaction, ratcheting extra-hardening under non-proportional loading (ii) provide local information (such us local stress/strain fields, damage, ….). A particular attention is paid to the identification process of material parameters. Moreover, finite element implementation of the Multi-Mechanism models is detailed.Table of ContentsPreface xi Introduction xiii Chapter 1. State of the Art 1 1.1. Motivation from the microstructure 1 1.2. Building bricks 6 1.2.1. Criteria 7 1.2.2. Isotropic hardening rules 12 1.2.3. Kinematic hardening rules (KHR) 17 1.2.4. Plastic modulus 19 1.2.5. Viscosity 24 1.3. Scale transition rules 27 1.3.1. General remarks on scale transition rules 27 1.3.2. Scale transition rules for the MM model 29 1.4. Large deformation 30 1.5. Brief history of the MM models 32 Chapter 2. Model Formulation 35 2.1. Thermodynamic framework 35 2.2. Model with various mechanisms and various criteria: the 2M2C model 37 2.3. Model with various mechanisms and one criterion: the 2M1C model 39 2.4. Comparison with the unified model 40 2.5. Isotropic hardening rules 41 2.5.1. Isotropic hardening for models with various mechanisms and one criterion 41 2.5.2. Isotropic hardening for models with various mechanisms and various criteria 43 2.6. Kinematic hardening rules 45 2.6.1. KHR: models with various mechanisms and various criteria 45 2.6.2. KHR: models with various mechanisms and one criterion 46 2.7. Computation of the inelastic multipliers 46 2.7.1. Flow rate for the 2M1C model 47 2.7.2. Flow rates for the 2M2C model 47 Chapter 3. Typical MM Responses 51 3.1. Some MM model variants 51 3.1.1. Initial MM models 51 3.1.2. Updated 2M1C models after [TAL 06] 53 3.1.3. Updated MM models after [SAÏ 07] 53 3.1.4. A general nMnC model 54 3.1.5. Generalization of the 2M1C model 56 3.2. Creep–plasticity interaction 56 3.3. Rate sensitivity for the 2M2C model 58 3.4. Stabilized behavior of viscoplastic 2M1C model 59 3.5. Closed-form solution for ratcheting behavior of the 2M2C model: case of linear kinematic hardening rules 60 3.6. Ratcheting for 2M1C model 64 3.7. Ratcheting behavior of the 10M10C model 67 3.8. Extra-hardening under non-proportional loading 69 3.9. Static recovery effect 72 Chapter 4. Comparison with Experimental Databases 77 4.1. Inconel 718 79 4.1.1. Context of the case study 79 4.1.2. Particular model features 79 4.1.3. Numerical results 79 4.2. Deformation mechanisms of Ni–Ti shape memory alloy 80 4.2.1. Context of the case study 80 4.2.2. Particular model features 82 4.2.3. Numerical results 82 4.3. N18 alloy 83 4.3.1. Context of the case study 83 4.3.2. Particular model features 84 4.3.3. Numerical results 85 4.4. Carbon steel CS1026 87 4.4.1. Context of the case study 87 4.4.2. Particular model features 87 4.4.3. Numerical results 88 4.5. Thermo-mechanical behavior of 55NiCrMoV7 89 4.5.1. Context of the case study 89 4.5.2. Particular model features 90 4.5.3. Numerical results 91 4.6. 2017 Aluminum alloy 94 4.6.1. 2017A, [SAÏ 12] 94 4.6.2. 2017A, [TAL 15] 97 4.7. 304 austenitic stainless steel 101 4.7.1. 304SS at room temperature [HAS 08] 101 4.7.2. 304SS at room temperature [TAL 11] 102 4.7.3. 304SS at 350◦C [TAL 14] 105 4.7.4. 304SS at room temperature [HAS 94a], 2M1C-3M1C 107 4.7.5. 304SS at room temperature [HAS 08, TAL 10], 2M1C-3M1C 112 4.8. 316 austenitic stainless steel 116 4.8.1. 316SS at room temperature [POR 00] 116 4.8.2. 316SS at room temperature [TAL 15] 119 4.8.3. 316SS at 350◦C [TAL 13b, TAL 14] 121 4.8.4. 316SS at room temperature [POR 00], 3M1C model 123 4.9. Recrystallized Zirconium alloy 4 [PRI 08] 124 4.9.1. Context of the case study 124 4.9.2. Particular model features 125 4.9.3. Numerical results 126 4.10. Semi-crystalline polymers [REG 09b] 126 4.10.1. Context of the case study 126 4.10.2. Particular model features 128 4.10.3. Numerical results 128 4.11. Glassy polymers [JER 14] 131 4.11.1. Context of the case study 131 4.11.2. Particular model features 132 4.11.3. Numerical results 133 4.12. Copper-zinc alloy CuZn27 [TAL 15] 136 4.12.1. Context of the case study 136 4.12.2. Numerical results 136 4.13. Ferritic steel 35NiCrMo16 [TAL 15] 139 4.13.1. Context of the case study 139 4.13.2. Numerical results 139 4.14. Ferritic steel XC18 [TAL 13a] 141 4.14.1. Context of the case study 141 4.14.2. Numerical results 141 4.15. Phase transformation in titanium alloys Ti6Al4V [LON 09] 143 4.15.1. Context of the case study 143 4.15.2. Particular model features 143 4.15.3. Numerical results 144 Chapter 5. MM Damage-Plasticity Models 147 5.1. MM models based on the GTN approach 148 5.1.1. Damage in the 2M1C model based on the GTN approach 149 5.1.2. Damage in the 2M2C model based on the GTN approach 150 5.2. MM models coupled with CDM theory 151 5.2.1. 2M1C model “Strain Equivalence” 153 5.2.2. 2M2C model “Strain Equivalence” 154 5.2.3. 2M1C model “Energy Equivalence” 156 5.2.4. 2M2C model “Energy Equivalence” 157 5.3. Two plastic mechanisms combined with a damage mechanism 159 5.4. MM models taking into account volume change (CDM theory) 162 5.4.1. 2M2C model for compressible materials, CDM theory 165 5.4.2. MM models for compressible materials, CDM theory, two damage variables 167 5.5. Damage behavior of mortar-rubber aggregate mixtures 167 Chapter 6. Finite Element Implementation 171 6.1. Implementations of particular models 171 6.1.1. Basic version of the 2M1C model 172 6.1.2. β models 175 6.2. Creep–plasticity interaction in a notched specimen 183 6.3. FE analysis of plane forging of polycarbonate specimens 184 6.4. FE simulation of bulging of a 304SS sheet 188 6.5. FE simulation of PA6 notched specimens 189 6.6. Finite Element codes 198 6.6.1. ZeBuLoN: explicit integration 198 6.6.2. ABAQUS: explicit integration 199 6.6.3. ANSYS: explicit integration 206 6.6.4. ZeBuLoN: implicit integration 214 6.6.5. ABAQUS: implicit integration 216 6.6.6. ANSYS: implicit integration 233 Bibliography 253 Index 265

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Book SynopsisThis volume considers the shock response spectrum, its various definitions, properties and the assumptions involved in its calculation. In developing the practical application of these concepts, the forms of shock most often used with test facilities are presented together with their characteristics and indications of how to establish test configurations comparable with those in the real, measured environment. This is followed by a demonstration of how to meet these specifications using standard laboratory equipment – shock machines, electrodynamic exciters driven by a time signal or a response spectrum – with a discussion on the limitations, advantages and disadvantages of each method.Table of ContentsForeword to Series xiii Introduction xvii List of Symbols xix Chapter 1. Shock Analysis 1 1.1. Definitions 1 1.1.1. Shock 1 1.1.2. Transient signal 2 1.1.3. Jerk 3 1.1.4. Simple (or perfect) shock 3 1.1.5. Half-sine shock 3 1.1.6. Versed sine (or haversine) shock 4 1.1.7. Terminal peak sawtooth (TPS) shock (or final peak sawtooth FPS)) 5 1.1.8. Initial peak sawtooth (IPS) shock 6 1.1.9. Square shock 7 1.1.10. Trapezoidal shock 8 1.1.11. Decaying sinusoidal pulse 8 1.1.12. Bump test 9 1.1.13. Pyroshock 9 1.2. Analysis in the time domain 12 1.3. Temporal moments 12 1.4. Fourier transform 15 1.4.1. Definition 15 1.4.2. Reduced Fourier transform 17 1.4.3. Fourier transforms of simple shocks 17 1.4.4. What represents the Fourier transform of a shock? 29 1.4.5. Importance of the Fourier transform 31 1.5. Energy spectrum 32 1.5.1. Energy according to frequency 32 1.5.2. Average energy spectrum 33 1.6. Practical calculations of the Fourier transform 33 1.6.1. General 33 1.6.2. Case: signal not yet digitized 33 1.6.3. Case: signal already digitized 36 1.6.4. Adding zeros to the shock signal before the calculation of its Fourier transform 37 1.6.5. Windowing 40 1.7. The interest of time-frequency analysis 41 1.7.1. Limit of the Fourier transform 41 1.7.2. Short term Fourier transform (STFT) 44 1.7.3. Wavelet transform 49 Chapter 2. Shock Response Spectrum 55 2.1. Main principles 55 2.2. Response of a linear one-degree-of-freedom system 59 2.2.1. Shock defined by a force 59 2.2.2. Shock defined by an acceleration 60 2.2.3. Generalization 60 2.2.4. Response of a one-degree-of-freedom system to simple shocks 65 2.3. Definitions 69 2.3.1. Response spectrum 69 2.3.2. Absolute acceleration SRS 69 2.3.3. Relative displacement shock spectrum 70 2.3.4. Primary (or initial) positive SRS 70 2.3.5. Primary (or initial) negative SRS 70 2.3.6. Secondary (or residual) SRS 71 2.3.7. Positive (or maximum positive) SRS 71 2.3.8. Negative (or maximum negative) SRS 71 2.3.9. Maximax SRS 72 2.4. Standardized response spectra 73 2.4.1. Definition 73 2.4.2. Half-sine pulse 75 2.4.3. Versed sine pulse 76 2.4.4. Terminal peak sawtooth pulse 78 2.4.5. Initial peak sawtooth pulse 79 2.4.6. Square pulse 81 2.4.7. Trapezoidal pulse 81 2.5. Choice of the type of SRS 82 2.6. Comparison of the SRS of the usual simple shapes 83 2.7. SRS of a shock defined by an absolute displacement of the support 84 2.8. Influence of the amplitude and the duration of the shock on its SRS 84 2.9. Difference between SRS and extreme response spectrum (ERS) 86 2.10. Algorithms for calculation of the SRS 86 2.11. Subroutine for the calculation of the SRS 86 2.12. Choice of the sampling frequency of the signal 90 2.13. Example of use of the SRS 94 2.14. Use of SRS for the study of systems with several degrees of freedom 96 2.15. Damage boundary curve 100 Chapter 3. Properties of Shock Response Spectra 103 3.1. Shock response spectra domains 103 3.2. Properties of SRS at low frequencies 104 3.2.1. General properties 104 3.2.2. Shocks with zero velocity change 104 3.2.3. Shocks with ΔV = 0 and ΔD ≠ 0 at the end of a pulse 115 3.2.4. Shocks with ΔV = 0 and ΔD = 0 at the end of a pulse 117 3.2.5. Notes on residual spectrum 120 3.3. Properties of SRS at high frequencies 121 3.4. Damping influence 124 3.5. Choice of damping 124 3.6. Choice of frequency range 127 3.7. Choice of the number of points and their distribution 128 3.8. Charts 131 3.9. Relation of SRS with Fourier spectrum 134 3.9.1. Primary SRS and Fourier transform 134 3.9.2. Residual SRS and Fourier transform 136 3.9.3. Comparison of the relative severity of several shocks using their Fourier spectra and their shock response spectra 139 3.10. Care to be taken in the calculation of the spectra 143 3.10.1. Main sources of errors 143 3.10.2. Influence of background noise of the measuring equipment 143 3.10.3. Influence of zero shift 145 3.11. Specific case of pyroshocks 152 3.11.1. Acquisition of the measurements 152 3.11.2. Examination of the signal before calculation of the SRS 154 3.11.3. Examination of the SRS 155 3.12. Pseudo-velocity shock spectrum 156 3.12.1. Hunt’s relationship 156 3.12.2. Interest of PVSS 160 3.13. Use of the SRS for pyroshocks 162 3.14. Other propositions of spectra165 3.14.1. Pseudo-velocity calculated from the energy transmitted 165 3.14.2. Pseudo-velocity from the “input” energy at the end of a shock 165 3.14.3. Pseudo-velocity from the unit “input” energy 167 3.14.4. SRS of the “total” energy 167 Chapter 4. Development of Shock Test Specifications 175 4.1. Introduction 175 4.2. Simplification of the measured signal 176 4.3. Use of shock response spectra 178 4.3.1. Synthesis of spectra 178 4.3.2. Nature of the specification 180 4.3.3. Choice of shape 181 4.3.4. Amplitude 182 4.3.5. Duration 182 4.3.6. Difficulties 186 4.4. Other methods 187 4.4.1. Use of a swept sine 188 4.4.2. Simulation of SRS using a fast swept sine 189 4.4.3. Simulation by modulated random noise 193 4.4.4. Simulation of a shock using random vibration 194 4.4.5. Least favorable response technique 195 4.4.6. Restitution of an SRS by a series of modulated sine pulses 196 4.5. Interest behind simulation of shocks on shaker using a shock spectrum 198 Chapter 5. Kinematics of Simple Shocks 203 5.1. Introduction 203 5.2. Half-sine pulse 203 5.2.1. General expressions of the shock motion 203 5.2.2. Impulse mode 206 5.2.3. Impact mode 207 5.3. Versed sine pulse 216 5.4. Square pulse 218 5.5. Terminal peak sawtooth pulse 221 5.6. Initial peak sawtooth pulse 223 Chapter 6. Standard Shock Machines 225 6.1. Main types 225 6.2. Impact shock machines 227 6.3. High impact shock machines 237 6.3.1. Lightweight high impact shock machine 237 6.3.2. Medium weight high impact shock machine 238 6.4. Pneumatic machines 239 6.5. Specific testing facilities 241 6.6. Programmers 242 6.6.1. Half-sine pulse 242 6.6.2. TPS shock pulse 250 6.6.3. Square pulse − trapezoidal pulse 258 6.6.4. Universal shock programmer 258 Chapter 7. Generation of Shocks Using Shakers 267 7.1. Principle behind the generation of a signal with a simple shape versus time 267 7.2. Main advantages of the generation of shock using shakers 268 7.3. Limitations of electrodynamic shakers 269 7.3.1. Mechanical limitations 269 7.3.2. Electronic limitations 271 7.4. Remarks on the use of electrohydraulic shakers 271 7.5. Pre- and post-shocks 271 7.5.1. Requirements 271 7.5.2. Pre-shock or post-shock 273 7.5.3. Kinematics of the movement for symmetric pre- and post-shock 276 7.5.4. Kinematics of the movement for a pre-shock or a post-shock alone 286 7.5.5. Abacuses 288 7.5.6. Influence of the shape of pre- and post-pulses 289 7.5.7. Optimized pre- and post-shocks 292 7.6. Incidence of pre- and post-shocks on the quality of simulation 297 7.6.1. General 297 7.6.2. Influence of the pre- and post-shocks on the time history response of a one-degree-of-freedom system 297 7.6.3. Incidence on the shock response spectrum 300 Chapter 8. Control of a Shaker Using a Shock Response Spectrum 303 8.1. Principle of control using a shock response spectrum 303 8.1.1. Problems 303 8.1.2. Parallel filter method 304 8.1.3. Current numerical methods 305 8.2. Decaying sinusoid 310 8.2.1. Definition 310 8.2.2. Response spectrum 311 8.2.3. Velocity and displacement 314 8.2.4. Constitution of the total signal 315 8.2.5. Methods of signal compensation 316 8.2.6. Iterations 323 8.3. D.L. Kern and C.D. Hayes’ function 324 8.3.1. Definition 324 8.3.2. Velocity and displacement 325 8.4. ZERD function 326 8.4.1. Definition 326 8.4.2. Velocity and displacement 328 8.4.3. Comparison of ZERD waveform with standard decaying sinusoid 330 8.4.4. Reduced response spectra 330 8.5. WAVSIN waveform 332 8.5.1. Definition 332 8.5.2. Velocity and displacement 333 8.5.3. Response of a one-degree-of-freedom system 335 8.5.4. Response spectrum 338 8.5.5. Time history synthesis from shock spectrum 339 8.6. SHOC waveform 340 8.6.1. Definition 340 8.6.2. Velocity and displacement 342 8.6.3. Response spectrum 343 8.6.4. Time history synthesis from shock spectrum 345 8.7. Comparison of WAVSIN, SHOC waveforms and decaying sinusoid 346 8.8. Waveforms based on the cosm(x) window 346 8.9. Use of a fast swept sine 348 8.10. Problems encountered during the synthesis of the waveforms 351 8.11. Criticism of control by SRS 353 8.12. Possible improvements 357 8.12.1. IES proposal 357 8.12.2. Specification of a complementary parameter 358 8.12.3. Remarks on the properties of the response spectrum 363 8.13. Estimate of the feasibility of a shock specified by its SRS363 8.13.1. C.D. Robbins and E.P. Vaughan’s method 363 8.13.2. Evaluation of the necessary force, power and stroke 365 Chapter 9. Simulation of Pyroshocks 371 9.1. Simulations using pyrotechnic facilities 371 9.2. Simulation using metal to metal impact 375 9.3. Simulation using electrodynamic shakers 377 9.4. Simulation using conventional shock machines 378 Appendix. Similitude in Mechanics 381 A1. Conservation of materials 381 A2. Conservation of acceleration and stress 383 Mechanical Shock Tests: A Brief Historical Background 385 Bibliography 387 Index 407 Summary of other Volumes in the series 413

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Book SynopsisThe vast majority of vibrations encountered in the real environment are random in nature. Such vibrations are intrinsically complicated and this volume describes the process that enables us to simplify the required analysis, along with the analysis of the signal in the frequency domain. The power spectrum density is also defined, together with the requisite precautions to be taken in its calculations as well as the processes (windowing, overlapping) necessary to obtain improved results. An additional complementary method – the analysis of statistical properties of the time signal – is also described. This enables the distribution law of the maxima of a random Gaussian signal to be determined and simplifies the calculation of fatigue damage by avoiding direct peak counting.Table of ContentsForeword to Series xiii Introduction xvii List of Symbols xix Chapter 1 Statistical Properties of a Random Process 1 1.1 Definitions 1 1.1.1 Random variable 1 1.1.2 Random process 2 1.2 Random vibration in real environments 2 1.3 Random vibration in laboratory tests 3 1.4 Methods of random vibration analysis 3 1.5 Distribution of instantaneous values 5 1.5.1 Probability density 5 1.5.2 Distribution function 6 1.6 Gaussian random process 7 1.7 Rayleigh distribution 12 1.8 Ensemble averages: through the process 12 1.8.1 n order average 12 1.8.2 Centered moments 14 1.8.3 Variance 14 1.8.4 Standard deviation 15 1.8.5 Autocorrelation function 16 1.8.6 Cross-correlation function 16 1.8.7 Autocovariance 17 1.8.8 Covariance 17 1.8.9 Stationarity 17 1.9 Temporal averages: along the process 23 1.9.1 Mean 23 1.9.2 Quadratic mean – rms value 25 1.9.3 Moments of order n 27 1.9.4 Variance – standard deviation 28 1.9.5 Skewness 29 1.9.6 Kurtosis 30 1.9.7 Crest Factor 33 1.9.8 Temporal autocorrelation function 33 1.9.9 Properties of the autocorrelation function 39 1.9.10 Correlation duration 41 1.9.11 Cross-correlation 47 1.9.12 Cross-correlation coefficient 50 1.9.13 Ergodicity 50 1.10 Significance of the statistical analysis (ensemble or temporal) 52 1.11 Stationary and pseudo-stationary signals 52 1.12 Summary chart of main definitions 53 1.13 Sliding mean 54 1.14 Test of stationarity 58 1.14.1 The reverse arrangements test (RAT) 58 1.14.2 The runs test 61 1.15 Identification of shocks and/or signal problems 65 1.16 Breakdown of vibratory signal into “events”: choice of signal samples 68 1.17 Interpretation and taking into account of environment variation 75 Chapter 2 Random Vibration Properties in the Frequency Domain 79 2.1 Fourier transform 79 2.2 Power spectral density 81 2.2.1 Need 81 2.2.2 Definition 82 2.3 Amplitude Spectral Density 89 2.4 Cross-power spectral density 89 2.5 Power spectral density of a random process 90 2.6 Cross-power spectral density of two processes 91 2.7 Relationship between the PSD and correlation function of a process 93 2.8 Quadspectrum – cospectrum 93 2.9 Definitions 94 2.9.1 Broadband process 94 2.9.2 White noise 95 2.9.3 Band-limited white noise 95 2.9.4 Narrow band process 96 2.9.5 Colors of noise 97 2.10 Autocorrelation function of white noise 98 2.11 Autocorrelation function of band-limited white noise 99 2.12 Peak factor 101 2.13 Effects of truncation of peaks of acceleration signal on the PSD 101 2.14 Standardized PSD/density of probability analogy 105 2.15 Spectral density as a function of time106 2.16 Sum of two random processes 106 2.17 Relationship between the PSD of the excitation and the response of a linear system 108 2.18 Relationship between the PSD of the excitation and the cross-power spectral density of the response of a linear system 111 2.19 Coherence function 112 2.20 Transfer function calculation from random vibration measurements 114 2.20.1 Theoretical relations 114 2.20.2 Presence of noise on the input 116 2.20.3 Presence of noise on the response 118 2.20.4 Presence of noise on the input and response 120 2.20.5 Choice of transfer function 121 Chapter 3 Rms Value of Random Vibration 127 3.1 Rms value of a signal as a function of its PSD 127 3.2 Relationships between the PSD of acceleration, velocity and displacement 131 3.3 Graphical representation of the PSD 133 3.4 Practical calculation of acceleration, velocity and displacement rms values 135 3.4.1 General expressions 135 3.4.2 Constant PSD in frequency interval 135 3.4.3 PSD comprising several horizontal straight line segments 137 3.4.4 PSD defined by a linear segment of arbitrary slope 137 3.4.5 PSD comprising several segments of arbitrary slopes 147 3.5 Rms value according to the frequency 147 3.6 Case of periodic signals 149 3.7 Case of a periodic signal superimposed onto random noise 151 Chapter 4 Practical Calculation of the Power Spectral Density 153 4.1 Sampling of signal 153 4.2 PSD calculation methods 158 4.2.1 Use of the autocorrelation function 158 4.2.2 Calculation of the PSD from the rms value of a filtered signal 158 4.2.3 Calculation of PSD starting from a Fourier transform 159 4.3 PSD calculation steps 160 4.3.1 Maximum frequency 160 4.3.2 Extraction of sample of duration T160 4.3.3 Averaging 167 4.3.4 Addition of zeros 170 4.4 FFT 175 4.5 Particular case of a periodic excitation 177 4.6 Statistical error 178 4.6.1 Origin 178 4.6.2 Definition 180 4.7 Statistical error calculation 180 4.7.1 Distribution of the measured PSD 180 4.7.2 Variance of the measured PSD 183 4.7.3 Statistical error 183 4.7.4 Relationship between number of degrees of freedom, duration and bandwidth of analysis 184 4.7.5 Confidence interval 190 4.7.6 Expression for statistical error in decibels 202 4.7.7 Statistical error calculation from digitized signal 204 4.8 Influence of duration and frequency step on the PSD 212 4.8.1 Influence of duration 212 4.8.2 Influence of the frequency step 213 4.8.3 Influence of duration and of constant statistical error frequency step 214 4.9 Overlapping 216 4.9.1 Utility 216 4.9.2 Influence on the number of degrees of freedom 217 4.9.3 Influence on statistical error 218 4.9.4 Choice of overlapping rate 221 4.10 Information to provide with a PSD 222 4.11 Difference between rms values calculated from a signal according to time and from its PSD 222 4.12 Calculation of a PSD from a Fourier transform 223 4.13 Amplitude based on frequency: relationship with the PSD 227 4.14 Calculation of the PSD for given statistical error 228 4.14.1 Case study: digitization of a signal is to be carried out 228 4.14.2 Case study: only one sample of an already digitized signal is available 230 4.15 Choice of filter bandwidth 231 4.15.1 Rules 231 4.15.2 Bias error 233 4.15.3 Maximum statistical error 238 4.15.4 Optimum bandwidth 240 4.16 Probability that the measured PSD lies between ± one standard deviation 243 4.17 Statistical error: other quantities 245 4.18 Peak hold spectrum 250 4.19 Generation of random signal of given PSD 252 4.19.1 Random phase sinusoid sum method 252 4.19.2 Inverse Fourier transform method 255 4.20 Using a window during the creation of a random signal from a PSD 256 Chapter 5 Statistical Properties of Random Vibration in the Time Domain 259 5.1 Distribution of instantaneous values 259 5.2 Properties of derivative process 260 5.3 Number of threshold crossings per unit time 264 5.4 Average frequency 269 5.5 Threshold level crossing curves 272 5.6 Moments 279 5.7 Average frequency of PSD defined by straight line segments 282 5.7.1 Linear-linear scales 282 5.7.2 Linear-logarithmic scales 284 5.7.3 Logarithmic-linear scales 285 5.7.4 Logarithmic-logarithmic scales 286 5.8 Fourth moment of PSD defined by straight line segments 288 5.8.1 Linear-linear scales 288 5.8.2 Linear-logarithmic scales 289 5.8.3 Logarithmic-linear scales 290 5.8.4 Logarithmic-logarithmic scales 291 5.9 Generalization: moment of order n 292 5.9.1 Linear-linear scales 292 5.9.2 Linear-logarithmic scales 292 5.9.3 Logarithmic-linear scales 292 5.9.4 Logarithmic-logarithmic scales 293 Chapter 6 Probability Distribution of Maxima of Random Vibration 295 6.1 Probability density of maxima 295 6.2 Moments of the maxima probability distribution 303 6.3 Expected number of maxima per unit time 304 6.4 Average time interval between two successive maxima 307 6.5 Average correlation between two successive maxima 308 6.6 Properties of the irregularity factor 309 6.6.1 Variation interval 309 6.6.2 Calculation of irregularity factor for band-limited white noise 313 6.6.3 Calculation of irregularity factor for noise of form G = Const.f b 316 6.6.4 Case study: variations of irregularity factor for two narrowband signals 320 6.7 Error related to the use of Rayleigh’s law instead of a complete probability density function 321 6.8 Peak distribution function 323 6.8.1 General case 323 6.8.2 Particular case of narrowband Gaussian process 325 6.9 Mean number of maxima greater than the given threshold (by unit time) 328 6.10 Mean number of maxima above given threshold between two times 331 6.11 Mean time interval between two successive maxima 331 6.12 Mean number of maxima above given level reached by signal excursion above this threshold 332 6.13 Time during which the signal is above a given value 335 6.14 Probability that a maximum is positive or negative 337 6.15 Probability density of the positive maxima 337 6.16 Probability that the positive maxima is lower than a given threshold 338 6.17 Average number of positive maxima per unit of time 338 6.18 Average amplitude jump between two successive extrema 339 6.19 Average number of inflection points per unit of time 341 Chapter 7 Statistics of Extreme Values 343 7.1 Probability density of maxima greater than a given value 343 7.2 Return period 344 7.3 Peak lp expected among Np peaks 344 7.4 Logarithmic rise 345 7.5 Average maximum of Np peaks 346 7.6 Variance of maximum 346 7.7 Mode (most probable maximum value) 346 7.8 Maximum value exceeded with risk α 346 7.9 Application to the case of a centered narrowband normal process 346 7.9.1 Distribution function of largest peaks over duration T 346 7.9.2 Probability that one peak at least exceeds a given threshold 349 7.9.3 Probability density of the largest maxima over duration T 350 7.9.4 Average of highest peaks 353 7.9.5 Mean value probability 355 7.9.6 Standard deviation of highest peaks 356 7.9.7 Variation coefficient 357 7.9.8 Most probable value 358 7.9.9 Median 358 7.9.10 Value of density at mode 360 7.9.11 Value of distribution function at mode 361 7.9.12 Expected maximum 361 7.9.13 Maximum exceeded with given risk α 361 7.10 Wideband centered normal process 363 7.10.1 Average of largest peaks 363 7.10.2 Variance of the largest peaks 366 7.10.3 Variation coefficient 367 7.11 Asymptotic laws 368 7.11.1 Gumbel asymptote 368 7.11.2 Case study: Rayleigh peak distribution 369 7.11.3 Expressions for large values of Np 370 7.12 Choice of type of analysis 371 7.13 Study of the envelope of a narrowband process 374 7.13.1 Probability density of the maxima of the envelope 374 7.13.2 Distribution of maxima of envelope 379 7.13.3 Average frequency of envelope of narrowband noise 381 Chapter 8 Response of a One-Degree-of-Freedom Linear System to Random Vibration 385 8.1 Average value of the response of a linear system 385 8.2 Response of perfect bandpass filter to random vibration 386 8.3 The PSD of the response of a one-dof linear system 388 8.4 Rms value of response to white noise 389 8.5 Rms value of response of a linear one-degree of freedom system subjected to bands of random noise 395 8.5.1 Case where the excitation is a PSD defined by a straight line segment in logarithmic scales 395 8.5.2 Case where the vibration has a PSD defined by a straight line segment of arbitrary slope in linear scales 401 8.5.3 Case where the vibration has a constant PSD between two frequencies 404 8.5.4 Excitation defined by an absolute displacement 409 8.5.5 Case where the excitation is defined by PSD comprising n straight line segments 411 8.6 Rms value of the absolute acceleration of the response 414 8.7 Transitory response of a dynamic system under stationary random excitation 415 8.8 Transitory response of a dynamic system under amplitude modulated white noise excitation 423 Chapter 9 Characteristics of the Response of a One-Degree-of-Freedom Linear System to Random Vibration 427 9.1 Moments of response of a one-degree-of-freedom linear system: irregularity factor of response 427 9.1.1 Moments 427 9.1.2 Irregularity factor of response to noise of a constant PSD 431 9.1.3 Characteristics of irregularity factor of response 433 9.1.4 Case of a band-limited noise 444 9.2 Autocorrelation function of response displacement 445 9.3 Average numbers of maxima and minima per second 446 9.4 Equivalence between the transfer functions of a bandpass filter and a one-degree-of-freedom linear system 449 9.4.1 Equivalence suggested by D.M Aspinwall 449 9.4.2 Equivalence suggested by K.W Smith 451 9.4.3 Rms value of signal filtered by the equivalent bandpass filter 453 Chapter 10 First Passage at a Given Level of Response of a One-Degree-of-Freedom Linear System to a Random Vibration 455 10.1 Assumptions 455 10.2 Definitions 459 10.3 Statistically independent threshold crossings 460 10.4 Statistically independent response maxima 468 10.5 Independent threshold crossings by the envelope of maxima 472 10.6 Independent envelope peaks 476 10.6.1 S.H Crandall method 476 10.6.2 D.M Aspinwall method 479 10.7 Markov process assumption 486 10.7.1 W.D Mark assumption 486 10.7.2 J.N Yang and M Shinozuka approximation 493 10.8 E.H Vanmarcke model 494 10.8.1 Assumption of a two state Markov process 494 10.8.2 Approximation based on the mean clump size 500 Appendix 511 Bibliography 571 Index 591 Summary of Other Volumes in the Series 597

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Book SynopsisFatigue damage in a system with one degree of freedom is one of the two criteria applied when comparing the severity of vibratory environments. The same criterion is also used for a specification representing the effects produced by the set of vibrations imposed in a real environment. In this volume, which is devoted to the calculation of fatigue damage, Christian Lalanne explores the hypotheses adopted to describe the behavior of material affected by fatigue and the laws of fatigue accumulation. The author also considers the methods for counting response peaks, which are used to establish the histogram when it is not possible to use the probability density of the peaks obtained with a Gaussian signal. The expressions for mean damage and its standard deviation are established and other hypotheses are tested.Table of ContentsForeword to Series xiii Introduction xvii List of Symbols xix Chapter 1. Concepts of Material Fatigue 1 1.1. Introduction 1 1.1.1. Reminders on the strength of materials 1 1.1.2. Fatigue 9 1.2. Types of dynamic loads (or stresses) 10 1.2.1. Cyclic stress 10 1.2.2. Alternating stress 12 1.2.3. Repeated stress 13 1.2.4. Combined steady and cyclic stress 13 1.2.5. Skewed alternating stress 14 1.2.6. Random and transitory stresses 14 1.3. Damage arising from fatigue 15 1.4. Characterization of endurance of materials 18 1.4.1. S-N curve 18 1.4.2. Influence of the average stress on the S-N curve 21 1.4.3. Statistical aspect 22 1.4.4. Distribution laws of endurance 23 1.4.5. Distribution laws of fatigue strength 26 1.4.6. Relation between fatigue limit and static properties of materials 28 1.4.7. Analytical representations of S-N curve 31 1.5. Factors of influence 41 1.5.1. General 41 1.5.2. Scale 42 1.5.3. Overloads 43 1.5.4. Frequency of stresses 44 1.5.5. Types of stresses 45 1.5.6. Non-zero mean stress 45 1.6. Other representations of S-N curves 48 1.6.1. Haigh diagram 48 1.6.2. Statistical representation of Haigh diagram 58 1.7. Prediction of fatigue life of complex structures 58 1.8. Fatigue in composite materials 59 Chapter 2. Accumulation of Fatigue Damage 61 2.1. Evolution of fatigue damage 61 2.2. Classification of various laws of accumulation 62 2.3. Miner’s method 63 2.3.1. Miner’s rule 63 2.3.2. Scatter of damage to failure as evaluated by Miner 67 2.3.3. Validity of Miner’s law of accumulation of damage in case of random stress 71 2.4. Modified Miner’s theory 73 2.4.1. Principle 73 2.4.2. Accumulation of damage using modified Miner’s rule 74 2.5. Henry’s method 77 2.6. Modified Henry’s method 79 2.7. Corten and Dolan’s method 79 2.8. Other theories 82 Chapter 3. Counting Methods for Analyzing Random Time History 85 3.1. General 85 3.2. Peak count method89 3.2.1. Presentation of method 89 3.2.2. Derived methods 92 3.2.3. Range-restricted peak count method 93 3.2.4. Level-restricted peak count method 93 3.3. Peak between mean-crossing count method 95 3.3.1. Presentation of method 95 3.3.2. Elimination of small variations 97 3.4. Range count method 98 3.4.1. Presentation of method 98 3.4.2. Elimination of small variations 100 3.5. Range-mean count method 101 3.5.1. Presentation of method 101 3.5.2. Elimination of small variations 104 3.6. Range-pair count method 106 3.7. Hayes’ counting method110 3.8. Ordered overall range counting method 112 3.9. Level-crossing count method 114 3.10. Peak valley peak counting method 118 3.11. Fatigue-meter counting method 123 3.12. Rainflow counting method 125 3.12.1. Principle of method 126 3.12.2. Subroutine for rainflow counting 131 3.13. NRL (National Luchtvaart Laboratorium) counting method 134 3.14. Evaluation of time spent at a given level 137 3.15. Influence of levels of load below fatigue limit on fatigue life 138 3.16. Test acceleration 138 3.17. Presentation of fatigue curves determined by random vibration tests 141 Chapter 4. Fatigue Damage by One-degree-of-freedom Mechanical System 143 4.1. Introduction 143 4.2. Calculation of fatigue damage due to signal versus time 144 4.3. Calculation of fatigue damage due to acceleration spectral density 146 4.3.1. General case 146 4.3.2. Particular case of a wideband response, e.g. at the limit r ?­ 0 151 4.3.3. Particular case of narrowband response 152 4.3.4. Rms response to narrowband noise G0 of width ?´f when G0 ?´ f ?­ constant 164 4.3.5. Steinberg approach 165 4.4. Equivalent narrowband noise 166 4.4.1. Use of relation established for narrowband response 167 4.4.2. Alternative: use of mean number of maxima per second 169 4.5. Calculation of damage from the modified Rice distribution of peaks 171 4.5.1. Approximation to real maxima distribution using a modified Rayleigh distribution 171 4.5.2. Wirsching and Light’s approach 175 4.5.3. Chaudhury and Dover’s approach 176 4.5.4. Approximate expression of the probability density of peaks 180 4.6. Other approaches 182 4.7. Calculation of fatigue damage from rainflow domains 185 4.7.1. Wirsching’s approach 185 4.7.2. Tunna’s approach 189 4.7.3. Ortiz-Chen’s method 191 4.7.4. Hancock’s approach 191 4.7.5. Abdo and Rackwitz’s approach 192 4.7.6. Kam and Dover’s approach 192 4.7.7. Larsen and Lutes (“single moment”) method 193 4.7.8. Jiao-Moan’s method 194 4.7.9. Dirlik’s probability density 195 4.7.10. Madsen’s approach 207 4.7.11. Zhao and Baker model 207 4.7.12. Tovo and Benasciutti method 208 4.8. Comparison of S-N curves established under sinusoidal and random loads 211 4.9. Comparison of theory and experiment 216 4.10. Influence of shape of power spectral density and value of irregularity factor 221 4.11. Effects of peak truncation 221 4.12. Truncation of stress peaks 222 4.12.1. Particular case of a narrowband noise 223 4.12.2. Layout of the S-N curve for a truncated distribution 232 Chapter 5. Standard Deviation of Fatigue Damage 237 5.1. Calculation of standard deviation of damage: Bendat’s method 237 5.2. Calculation of standard deviation of damage: Mark’s method 242 5.3. Comparison of Mark and Bendat’s results 247 5.4. Standard deviation of the fatigue life 253 5.4.1. Narrowband vibration 253 5.4.2. Wideband vibration 256 5.5. Statistical S-N curves 257 5.5.1. Definition of statistical curves 257 5.5.2. Bendat’s formulation 258 5.5.3. Mark’s formulation. 261 Chapter 6. Fatigue Damage using Other Calculation Assumptions 267 6.1. S-N curve represented by two segments of a straight line on logarithmic scales (taking into account fatigue limit) 267 6.2. S-N curve defined by two segments of straight line on log-lin scales 270 6.3. Hypothesis of non-linear accumulation of damage 273 6.3.1. Corten-Dolan’s accumulation law 273 6.3.2. Morrow’s accumulation model 275 6.4. Random vibration with non-zero mean: use of modified Goodman diagram 277 6.5. Non-Gaussian distribution of instantaneous values of signal 280 6.5.1. Influence of distribution law of instantaneous values 280 6.5.2. Influence of peak distribution 281 6.5.3. Calculation of damage using Weibull distribution 281 6.5.4. Comparison of Rayleigh assumption/peak counting 284 6.6. Non-linear mechanical system 286 Chapter 7. Low-cycle Fatigue 289 7.1. Overview 289 7.2. Definitions 290 7.2.1. Baushinger effect 290 7.2.2. Cyclic strain hardening 291 7.2.3. Properties of cyclic stress–strain curves 291 7.2.4. Stress–strain curve 291 7.2.5. Hysteresis and fracture by fatigue 295 7.2.6. Significant factors influencing hysteresis and fracture by fatigue 295 7.2.7. Cyclic stress–strain curve (or cyclic consolidation curve) 296 7.3. Behavior of materials experiencing strains in the oligocyclic domain 297 7.3.1. Types of behaviors 297 7.3.2. Cyclic strain hardening 297 7.3.3. Cyclic strain softening 299 7.3.4. Cyclically stable metals 300 7.3.5. Mixed behavior 301 7.4. Influence of the level application sequence 301 7.5. Development of the cyclic stress–strain curve 303 7.6. Total strain 304 7.7. Fatigue strength curve 305 7.8. Relation between plastic strain and number of cycles to fracture 306 7.8.1. Orowan relation 306 7.8.2. Manson relation 307 7.8.3. Coffin relation 307 7.8.4. Shanley relation 317 7.8.5. Gerberich relation 318 7.8.6. Sachs, Gerberich, Weiss and Latorre relation 318 7.8.7. Martin relation 318 7.8.8. Tavernelli and Coffin relation 319 7.8.9. Manson relation 319 7.8.10. Ohji et al. relation 321 7.8.11. Bui-Quoc et al. relation 321 7.9. Influence of the frequency and temperature in the plastic field 321 7.9.1. Overview 321 7.9.2. Influence of frequency 322 7.9.3. Influence of temperature and frequency 322 7.9.4. Effect of frequency on plastic strain range 324 7.9.5. Equation of generalized fatigue 325 7.10. Laws of damage accumulation 326 7.10.1. Miner rule 326 7.10.2. Yao and Munse relation 327 7.10.3. Use of the Manson–Coffin relation 329 7.11. Influence of an average strain or stress 329 7.12. Low-cycle fatigue of composite material 332 Chapter 8. Fracture Mechanics 335 8.1. Overview 335 8.2. Fracture mechanism 338 8.2.1. Major phases 338 8.2.2. Initiation of cracks 339 8.2.3. Slow propagation of cracks 341 8.3. Critical size: strength to fracture 341 8.4. Modes of stress application 343 8.5. Stress intensity factor 344 8.5.1. Stress in crack root 344 8.5.2. Mode I 346 8.5.3. Mode II 349 8.5.4. Mode III 350 8.5.5. Field of equation use 350 8.5.6. Plastic zone 352 8.5.7. Other form of stress expressions 354 8.5.8. General form 356 8.5.9. Widening of crack opening 357 8.6. Fracture toughness: critical K value 358 8.7. Calculation of the stress intensity factor 362 8.8. Stress ratio 365 8.9. Expansion of cracks: Griffith criterion 367 8.10. Factors affecting the initiation of cracks 369 8.11. Factors affecting the propagation of cracks 369 8.11.1. Mechanical factors 370 8.11.2. Geometric factors 372 8.11.3. Metallurgical factors 373 8.11.4. Factors linked to the environment 373 8.12. Speed of propagation of cracks 374 8.13. Effect of a non-zero mean stress 379 8.14. Laws of crack propagation 379 8.14.1. Head law 380 8.14.2. Modified Head law 381 8.14.3. Frost and Dugsdale 381 8.14.4. McEvily and Illg 382 8.14.5. Paris and Erdogan 383 8.15. Stress intensity factor 396 8.16. Dispersion of results 397 8.17. Sample tests: extrapolation to a structure 398 8.18. Determination of the propagation threshold KS 398 8.19. Propagation of cracks in the domain of low-cycle fatigue 400 8.20. Integral J 401 8.21. Overload effect: fatigue crack retardation 403 8.22. Fatigue crack closure 405 8.23. Rules of similarity 407 8.24. Calculation of a useful lifetime 407 8.25. Propagation of cracks under random load 410 8.25.1. Rms approach 411 8.25.2. Narrowband random loads 416 8.25.3. Calculation from a load collective 422 Appendix 427 Bibliography 441 Index 487 Summary of Other Volumes in the Series 491

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Book SynopsisOver the past two decades, the rapid development of nanochemistry and nanotechnology has allowed the synthesis of various materials and oxides in the form of nanopowders making it possible to produce new energetic compositions and nanomaterials. This book has a bottom-up structure, from nanomaterials synthesis to the application fields. Starting from aluminum nanoparticles synthesis for fuel application, it proposes a detailed state-of-the art of the different methods of preparation of aluminum-based reactive nanomaterials. It describes the techniques developed for their characterization and, when available, a description of the fundamental mechanisms responsible for their ignition and combustion. This book also presents the possibilities and limitations of different energetic nanomaterials and related structures as well as the analysis of their chemical and thermal properties. The whole is rounded off with a look at the performances of reactive materials in terms of heat of reaction and reactivity mainly characterized as the self-sustained combustion velocity. The book ends up with a description of current reactive nanomaterials applications underlying the promising integration of aluminum-based reactive nanomaterial into micro electromechanical systems.Table of ContentsINTRODUCTION ix ACKNOWLEDGEMENTS xi CHAPTER 1. NANOSIZED ALUMINUM AS METAL FUEL 1 1.1. Al nanoparticles manufacturing 2 1.1.1. Vapor-phase condensation methods 2 1.1.2. Wet chemistry 6 1.1.3. Mechanical methods 7 1.2. Example of Al nanoparticles passivation technique 8 1.2.1. Metallic coating 9 1.2.2. Organic coating 9 1.3. Characterization of Al nanoparticles properties 11 1.3.1. Light scattering methods 12 1.3.2. Gas adsorption method: specific surface measurement, BET diameter 13 1.3.3. Thermal analysis: purity or aluminum content percentage and oxide thickness 13 1.3.4. Chemical analysis 15 1.4. Oxidation of aluminum: basic chemistry and models 16 1.4.1. Initial stage of aluminum oxidation from first principles calculations 16 1.4.2. Thermodynamic modeling of Al oxidation under low heating rate 18 1.5. Why incorporate Al nanoparticles into propellant and rocket technology? 23 1.5.1. Reduction of the melting point 24 1.5.2. Increase in the reactivity 25 CHAPTER 2. APPLICATIONS: AL NANOPARTICLES IN GELLED PROPELLANTS AND SOLID FUELS 27 2.1. Gelled propellants 27 2.2. Solid propellants 29 2.3. Solid fuel 31 CHAPTER 3. APPLICATIONS OF AL NANOPARTICLES: NANOTHERMITES 33 3.1. Method of preparation 35 3.1.1. Ultrasonic nanopowder mixing 36 3.1.2. Rapid expansion of a supercritical dispersion 38 3.1.3. Molecular self-assembly of nanoparticles 39 3.2. Key parameters 42 3.2.1. The bulk density, theoretical density and compaction 42 3.2.2. The stochiometry 44 3.2.3. The size of Al and oxidizer particles 46 3.2.4. The passivation layer 49 3.3. Pressure generation tests 50 3.4. Combustion tests 52 3.4.1. Open tray experiments 52 3.4.2. Optical temperature measurement: spectroscopy 53 3.4.3. Photodiodes 54 3.4.4. Confined combustion tests 54 3.5. Ignition tests 56 3.5.1. Impact ignition 56 3.5.2. High-rate heating (106–107°C/s) 57 3.5.3. Low and uniform heating (10–100°C/s) 57 3.6. Electrostatic discharge (ESD) sensitivity tests 58 CHAPTER 4. OTHER REACTIVE NANOMATERIALS AND NANOTHERMITE SYSTEMS 63 4.1. Sol–gel materials 63 4.2. Reactive multilayered foils 66 4.2.1. Bimetallic multilayered foils 67 4.2.2. Thermite multilayered foils 72 4.2.3. Summary 77 4.3. Dense reactive materials 77 4.3.1. Arrested reactive milling 78 4.3.2. Cold-spray consolidation 81 4.4. Core–shell structures 83 4.5. Reactive porous silicon 86 4.6. Other energetic systems 88 CHAPTER 5. COMBUSTION AND PRESSURE GENERATION MECHANISMS 91 5.1. General views of Al particle combustion: micro versus nano, diffusion-based kinetics 93 5.2. Stress in the oxide layer and shrinking core model 95 5.3. Aluminum oxidation through diffusion-reaction mechanisms 97 5.4. Melt-dispersion mechanism 99 5.5. Gas and pressure generation in nanothermites 100 5.5.1. Thermodynamic models 100 5.5.2. Application to Al/CuO 103 CHAPTER 6. APPLICATIONS 107 6.1. Reactive bonding 108 6.2. Microignition chips 110 6.3. Microactuation/propulsion 113 6.3.1. High energetic actuators 113 6.3.2. Fast impulse nanothermite thrusters 113 6.3.3. Smooth actuators 116 6.4. Material processing and others 119 CONCLUSIONS 121 BIBLIOGRAPHY 125 INDEX 149

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Book SynopsisThis book addresses general information, good practices and examples about thermo-physical properties, thermo-kinetic and thermo-mechanical couplings, instrumentation in thermal science, thermal optimization and infrared radiation.Table of ContentsPreface xv Chapter 1 Introduction to Heat Transfer During the Forming of Organic Matrix Composites 1Didier Delaunay Chapter 2 Experimental Determination and Modeling of Thermorphysical Properties 29Nicolas Boyard and Didier Delaunay Chapter 3 Experimental Determination and Modeling of Transformation Kinetics 77Nicolas Boyard, Jean-Luc Bailleul and M'hamed Boutaous Chapter 4 Phase Change Kinetics within Process Conditions and Coupling with Heat Transfer 121M'hamed Boutaous, Mattieu Zinet, Nicolas Boyard and Jean-Luc Bailleul Chapter 5 From the Characterization and Modeling of Cure-Dependent Properties of Composite Materials to the Simulation of Residual Stresses 157Yasir Nawab and Frederic Jacquemin Chapter 6 Heat Transfer in Composite Materials and Porous Media: Multiple-Scale Aspects and Effective Properties 175Michel Quintard Chapter 7 Thermal Optimization of Forming Processes 203Vincent Sobotka Chapter 8 Modeling of Thermoplastic Welding 235Gilles Regnier and Steven Le Corre Chapter 9 Multiphysics for Simulation of Forming Processes 269Luisa Silva, Patrice Laure, Thierry Coupez and Hugues Digonnet Chapter 10 Thermal Instrumentation for the Control of Manufacturing Processes of Organic Matrix Composite Materials 301Jean-Christophe Batsale and Christophe Pradere Chapter 11 Sensors for Heat Flux Measurement 333Fabien Cara and Vincent Sobotka Chapter 12 Thermal Radiative Properties of Polymers and Associated Composites 359Benoit Rousseau Chapter 13 Infrared Radiation Applied to Polymer Processes 385Yannick Le Maoult and Fabrice Schmidt List of Authors 425 Index 427

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Book SynopsisComplex behavior models (plasticity, cracks, visco elascticity) face some theoretical difficulties for the determination of the behavior law at the continuous scale. When homogenization fails to give the right behavior law, a solution is to simulate the material at a meso scale in order to simulate directly a set of discrete properties that are responsible of the macroscopic behavior. The discrete element model has been developed for granular material. The proposed set shows how this method is capable to solve the problem of complex behavior that are linked to discrete meso scale effects. Table of ContentsLIST OF FIGURES ix LIST OF TABLES xv PREFACE xvii INTRODUCTION xxi CHAPTER 1. STATE OF THE ART: DISCRETE ELEMENT MODELING 1 1.1. Introduction 1 1.2. Classification of discrete methods 3 1.2.1. Quantum mechanical methods 4 1.2.2. Atomistic methods 5 1.2.3. Mesoscopic discrete methods 8 1.3. Discrete element method for continuous materials 16 1.4. Discrete-continuum transition: macroscopic variables 17 1.4.1. Stress tensor for discrete systems 18 1.4.2. Strain tensor for discrete systems 21 1.5. Conclusion 31 CHAPTER 2. DISCRETE ELEMENT MODELING OF MECHANICAL BEHAVIOR OF CONTINUOUS MATERIALS 33 2.1. Introduction 33 2.2. Explicit dynamic algorithm 35 2.3. Construction of the discrete domain 37 2.3.1. The cooker compaction algorithm 39 2.3.2. Geometrical characterization of the discrete domain 44 2.4. Mechanical behavior modeling 56 2.4.1. Cohesive beam model 58 2.4.2. Calibration of the cohesive beam static parameters 64 2.4.3. Calibration of the cohesive beam dynamic parameters 79 2.5. Conclusion 87 CHAPTER 3. DISCRETE ELEMENT MODELING OF THERMAL BEHAVIOR OF CONTINUOUS MATERIALS 93 3.1. Introduction 93 3.2. General description of the method 95 3.2.1. Characterization of field variable variation in discrete domain 95 3.2.2. Application to heat conduction 96 3.3. Thermal conduction in 3D ordered discrete domains 97 3.4. Thermal conduction in 3D disordered discrete domains 100 3.4.1. Determination of local parameters for each discrete element 102 3.4.2. Calculation of discrete element transmission surface 103 3.4.3. Calculation of local volume fraction 104 3.4.4. Interactions between each discrete element and its neighbors 105 3.5. Validation 106 3.5.1. Cylindrical beam in contact with a hot plane 106 3.5.2. Dynamically heated sheet 107 3.6. Conclusion 113 CHAPTER 4. DISCRETE ELEMENT MODELING OF BRITTLE FRACTURE 115 4.1. Introduction 115 4.2. Fracture model based on the cohesive beam bonds 118 4.2.1. Fracture criterion 118 4.2.2. Calibration 120 4.2.3. Convergence study 123 4.2.4. Validation 125 4.3. Fracture model based on the virial stress 132 4.3.1. Fracture criterion 132 4.3.2. Calibration 134 4.3.3. Convergence study 134 4.3.4. Validation 136 4.4. Conclusion 137 CONCLUSION 141 BIBLIOGRAPHY 145 INDEX 161

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Book SynopsisComplex behavior models (plasticity, crack, visco-elascticity) are facing several theoretical difficulties in determining the behavior law at the continuous (macroscopic) scale. When homogenization fails to give the right behavior law, a solution is to simulate the material at a mesoscale using the discrete element model (DEM) in order to directly simulate a set of discrete properties that are responsible for the macroscopic behavior. Originally, the discrete element model was developed for granular material. This book, the second in the Discrete Element Model and Simulation of Continuous Materials Behavior set of books, shows how to choose the adequate coupling parameters to avoid spurious wave reflection and to allow the passage of all the dynamic information both from the fine to the coarse model and vice versa. The authors demonstrate the coupling method to simulate a highly nonlinear dynamical problem: the laser shock processing of silica glass.Table of ContentsList of Figures ix List of Tables xv Preface xvii Introduction xix Part 1. Discrete-Continuum Coupling Method to Model Highly Dynamic Multi-Scale Problems 1 Chapter 1. State of the Art: Concurrent Discrete-continuum Coupling 3 1.1. Introduction 3 1.2. Coupling challenges 4 1.2.1. Dissimilar variables due to different mechanical bases 4 1.2.2. Wave reflections due to different analysis scales 4 1.3. Coupling techniques 10 1.3.1. Edge-to-edge coupling methods 11 1.3.2. Bridging domain coupling methods 15 1.3.3. Bridging-scale coupling methods 19 1.3.4. Other coupling techniques 23 1.4. Conclusion 25 Chapter 2. Choice of the Continuum Method to be Coupled with the Discrete Element Method 27 2.1. Introduction 27 2.2. Classification of the continuum methods 28 2.2.1. Grid-based methods 28 2.2.2. Meshless methods 33 2.3. Choice of continuum method 38 2.4. The constrained natural element method 41 2.4.1. Natural neighbor interpolation 41 2.4.2. Visibility criterion 48 2.4.3. Constrained natural neighbor interpolation 48 2.4.4. Numerical integration 49 2.5. Conclusion 51 Chapter 3. Development of Discrete-Continuum Coupling Method Between DEM and CNEM 53 3.1. Introduction 53 3.2. Discrete-continuum coupling method: DEM-CNEM 54 3.2.1. DEM-CNEM coupling formulation 54 3.2.2. Discretization and spatial integration 59 3.2.3. Time integration 62 3.2.4. Algorithmic 63 3.2.5. Implementation 66 3.3. Parametric study of the coupling parameters 67 3.3.1. Influence of the junction parameter l 71 3.3.2. Influence of the weight function α 73 3.3.3. Influence of the approximated mediator spaceM˜ 79 3.3.4. Influence of the width of the bridging zone LB 79 3.3.5. Dependence between LB andM˜ 81 3.4. Choice of the coupling parameters in practice 83 3.5. Validation 84 3.6. Conclusion 85 Part 2. Application: Simulation of Laser Shock Processing of Silica Glass 89 Chapter 4. Some Fundamental Concepts in Laser Shock Processing 91 4.1. Introduction 91 4.2. Theory of laser–matter interaction: high pressure generation 92 4.2.1. Generation of shock wave by laser ablation 93 4.2.2. Shock wave propagation in materials 96 4.2.3. Laser-induced damage in materials 106 4.3. Mechanical response of silica glass under high pressure 109 4.3.1. Silica glass response under quasi-static hydrostatic compression 109 4.3.2. Silica glass response under shock compression 114 4.3.3. Summary of the silica glass response under high pressure 118 4.4. Conclusion 119 Chapter 5. Modeling of the Silica Glass Mechanical Behavior 121 5.1. Introduction 121 5.2. Mechanical behavior modeling 122 5.2.1. Modeling assumption 123 5.2.2. Cohesive beam model 124 5.2.3. Quasi-static calibration and validation 127 5.2.4. Dynamic calibration and validation 139 5.3. Brittle fracture modeling 147 5.4. Conclusion 149 Chapter 6. Simulation of Laser Shock Processing of Silica Glass 151 6.1. Introduction 151 6.2. LSP test 153 6.3. LSP model 155 6.4. Results 159 6.5. Conclusion 163 Conclusion 165 Bibliography 171 Index 185

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Book SynopsisDedicated to SiC-based 1D nanostructures, this book explains the properties and different growth methods of these nanostructures. It details carburization of silicon nanowires, a growth process for obtaining original Si-SiC core-shell nanowires and SiC nanotubes of high crystalline quality, thanks to the control of the siliconout-diffusion. The potential applications of these particular nano-objects is also discussed, with regards to their eventual integration in biology, energy and electronics.Table of ContentsFOREWORD ix INTRODUCTION xiii LIST OF ACRONYMS xvii CHAPTER 1. PROPERTIES OF SIC-BASED ONE-DIMENSIONAL NANOSTRUCTURES 1 1.1. Intrinsic properties of silicon carbide 1 1.1.1. Crystallographic description 1 1.1.2. Physical and chemical properties of SiC 7 1.2. Properties of one-dimensional nanostructures 14 1.2.1. Definition and classification 14 1.2.2. High surface/volume ratio and its consequences 17 1.2.3. Specific properties at the nano metric scale 20 1.3. Conclusion 25 CHAPTER 2. STATE OF THE ART OF THE GROWTH OF SIC-1D NANOSTRUCTURES 27 2.1. State of the art of the growth of SiC nanowires 27 2.1.1. Silicidation of carbon nanotubes 28 2.1.2. Synthesis through the VLS mechanism 29 2.1.3. Development in the gaseous phase – VS mechanism 33 2.1.4. Carburization of Si nanowires 34 2.1.5. Conclusion on the growth of SiC nanowires 36 2.2. State of the art of the growth of SiC nanotubes 37 2.3. State of the art of the growth of SiC-based core–shell nanowires 39 2.3.1. Si–SiC core–shell nanowires 39 2.3.2. Other SiC-based core–shell nanowires 40 2.4. Conclusion 41 CHAPTER 3. AN ORIGINAL GROWTH PROCESS: THE CARBURIZATION OF SI NANOWIRES 43 3.1. Si nanowires 44 3.2. The carburization of bulk silicon 48 3.3. Experimental application 55 3.3.1. Carburization apparatus 55 3.3.2. Methods of characterization 56 3.4. Growth of core–shell Si–SiC nanowires 58 3.4.1. Introduction 58 3.4.2. Experimental study 59 3.5. Growth of silicon carbide nanotubes 73 3.5.1. Founding idea and experimental application 73 3.5.2. A word on the kinetics of carburization 77 3.6. Summary of the study of the carburization of silicon nanowires 79 3.6.1. Illustration of carburization mechanisms for the growth of Si–SiC nanowires or SiC nanotubes 79 3.6.2. The carburization of Si NW summarized: construction of an existence domain diagram 81 3.6.3. Criticism of the nanostructures obtained 84 CHAPTER 4. SIC-BASED ONE-DIMENSIONAL NANOSTRUCTURE TECHNOLOGIES 87 4.1. Top-down approach: SiC plasma etching for the production of SiC nanowires 87 4.2. Mechanics 90 4.3. Energy 91 4.4. Electronics 93 4.4.1. Integration of nanostructures in a nanowire transistor 93 4.5. For biology 99 4.6. Future work 100 CONCLUSION 103 BIBLIOGRAPHY 107 INDEX 127

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Book SynopsisThis book deals with the mechanics and physics of fractures at various scales. Based on advanced continuum mechanics of heterogeneous media, it develops a rigorous mathematical framework for single macrocrack problems as well as for the effective properties of microcracked materials. In both cases, two geometrical models of cracks are examined and discussed: the idealized representation of the crack as two parallel faces (the Griffith crack model), and the representation of a crack as a flat elliptic or ellipsoidal cavity (the Eshelby inhomogeneity problem). The book is composed of two parts: The first part deals with solutions to 2D and 3D problems involving a single crack in linear elasticity. Elementary solutions of cracks problems in the different modes are fully worked. Various mathematical techniques are presented, including Neuber-Papkovitch displacement potentials, complex analysis with conformal mapping and Eshelby-based solutions. The second part is devoted to continuum micromechanics approaches of microcracked materials in relation to methods and results presented in the first part. Various estimates and bounds of the effective elastic properties are presented. They are considered for the formulation and application of continuum micromechanics-based damage models. Table of ContentsNotations xiii Preface xv Part 1. Elastic Solutions to Single Crack Problems 1 Chapter 1. Fundamentals of Plane Elasticity 3 1.1. Complex representation of Airy’s biharmonic stress function 3 1.2. Force acting on a curve or an element of arc 7 1.3. Derivation of stresses 9 1.4. Derivation of displacements 11 1.5. General form of the potentials φ and ψ 12 1.6. Examples 15 1.6.1. Circular cavity under pressure 15 1.6.2. Circular cavity in a plane subjected to uniaxial traction at infinity 16 1.7. Conformal mapping 18 1.7.1. Application of conformal mapping to plane elasticity problems 18 1.7.2. The domain Σ is the unit disc |ζ| ≤ 1 20 1.7.3. The domain Σ is the complement Σ− of the unit disc 23 1.8. The anisotropic case 26 1.8.1. General features 26 1.8.2. Stresses, displacements and boundary conditions 28 1.9. Appendix: mathematical tools 29 1.9.1. Theorem 1 30 1.9.2. Theorem 2 31 1.9.3. Theorem 3 31 Chapter 2. Fundamentals of Elasticity in View of Homogenization Theory 33 2.1. Green's function concept 33 2.2. Green’s function in two-dimensional conditions 34 2.2.1. The general anisotropic case 34 2.2.2. The isotropic case 35 2.3. Green’s function in three-dimensional conditions 38 2.3.1. The general anisotropic case 38 2.3.2. The isotropic case 39 2.4. Eshelby’s problems in linear microelasticity 41 2.4.1. The (elastic) inclusion problem 41 2.4.2. The Green operator of the infinite space 44 2.4.3. The Green operator of a finite domain 48 2.4.4. The inhomogeneity problem 50 2.4.5. The inhomogeneity problem with stress boundary conditions 51 2.4.6. The infinite heterogeneous elastic medium 52 2.5. Hill tensor for the elliptic inclusion 54 2.5.1. Properties of the logarithmic potential 54 2.5.2. Integration of the r,ir,l term 57 2.5.3. Components of the Hill tensor 59 2.6. Hill’s tensor for the spheroidal inclusion 60 2.6.1. Components of the Hill tensor 63 2.6.2. Series expansions of the components of the Hill tensor for flat spheroids 64 2.7. Appendix 65 2.8. Appendix: derivation of the χij 67 Chapter 3. Two-dimensional Griffith Crack 71 3.1. Stress singularity at crack tip 72 3.1.1. Stress singularity in plane elasticity: modes I and II 73 3.1.2. Stress singularity in antiplane problems in elasticity: mode III 78 3.2. Solution to mode I problem 80 3.2.1. Solution of PI 82 3.2.2. Solution of PI 90 3.2.3. Displacement jump across the crack surfaces 91 3.3. Solution to mode II problem 92 3.3.1. Solution of PII 93 3.3.2. Solution of PII 96 3.3.3. Displacement jump across the crack surfaces 97 3.4. Appendix: Abel’s integral equation 98 3.5. Appendix: Neuber–Papkovitch displacement potentials 101 Chapter 4. The Elliptic Crack Model in Plane Strains 103 4.1. The infinite plane with elliptic hole 103 4.1.3. Elliptic cavity in a plane subjected to a remote stress state at infinity 107 4.1.4. Stress intensity factors 108 4.1.5. Some remarks on unilateral contact 111 4.2. Infinite plane with elliptic hole: the anisotropic case 112 4.2.1. General properties 112 4.2.2. Complex potentials for an elliptic cavity in the presence of traction at infinity 115 4.2.3. Complex potentials for an elliptic cavity in the case of shear at infinity 116 4.2.5. Displacement discontinuities 121 4.2.6. Closed cracks 123 4.3. Eshelby approach 130 4.3.1. Mode I 130 4.3.2. Mode II 133 Chapter 5. Griffith Crack in 3D 137 5.1. Griffith circular (penny-shaped) crack in mode I 138 5.1.1. Solution of PI 139 5.1.2. Solution of PI 143 5.2. Griffith circular (penny-shaped) crack under shear loading 144 5.2.1. Solution of PII 146 5.2.2. Solution of PII 151 Chapter 6. Ellipsoidal Crack Model: the Eshelby Approach 155 6.1. Mode I 156 6.2. Mode II 159 Chapter 7. Energy Release Rate and Conditions for Crack Propagation 163 7.1. Driving force of crack propagation 163 7.2. Stress intensity factor and energy release rate 167 Part 2. Homogenization of Microcracked Materials 173 Chapter 8. Fundamentals of Continuum Micromechanics 175 8.1. Scale separation 175 8.2. Inhomogeneity model for cracks 177 8.2.1. Uniform strain boundary conditions 177 8.2.2. Uniform stress boundary conditions 181 8.2.3. Linear elasticity with uniform strain boundary conditions 182 8.2.4. Linear elasticity with uniform stress boundary conditions 185 8.3. General results on homogenization with Griffith cracks 187 8.3.1. Hill’s lemma with Griffith cracks 187 8.3.2. Uniform strain boundary conditions 188 8.3.3. Uniform stress boundary conditions 190 8.3.4. Derivation of effective properties in linear elasticity: principle of the approach 190 8.3.5. Appendix 194 Chapter 9. Homogenization of Materials Containing Griffith Cracks 197 9.1. Dilute estimates in isotropic conditions 197 9.1.1. Stress-based dilute estimate of stiffness 199 9.1.2. Stress-based dilute estimate of stiffness with closed cracks 202 9.1.3. Strain-based dilute estimate of stiffness with opened cracks 204 9.1.4. Strain-based dilute estimate of stiffness with closed cracks 205 9.2. A refined strain-based scheme 206 9.3. Homogenization in plane strain conditions for anisotropic materials 208 9.3.1. Opened cracks 208 9.3.2. Closed cracks 211 Chapter 10. Eshelby-based Estimates of Strain Concentration and Stiffness 213 10.1. Dilute estimate of the strain concentration tensor: general features 213 10.1.1. The general case 213 10.2. The particular case of opened cracks 215 10.2.1. Spheroidal crack 215 10.2.2. Elliptic crack 216 10.2.3. Crack opening change 218 10.3. Dilute estimates of the effective stiffness for opened cracks 220 10.3.1. Opened parallel cracks 222 10.3.2. Opened randomly oriented cracks 224 10.4. Dilute estimates of the effective stiffness for closed cracks 226 10.4.1. Closed parallel cracks 228 10.4.2. Closed randomly oriented cracks 228 10.5. Mori–Tanaka estimate of the effective stiffness 229 10.5.1. Opened cracks 231 10.5.2. Closed cracks 233 Chapter 11. Stress-based Estimates of Stress Concentration and Compliance 235 11.1. Dilute estimate of the stress concentration tensor 235 11.2. Dilute estimates of the effective compliance for opened cracks 236 11.2.1. Opened parallel cracks 237 11.2.2. Opened randomly oriented cracks 239 11.2.3. Discussion 239 11.3. Dilute estimate of the effective compliance for closed cracks 240 11.3.1. 3D case 241 11.3.2. 2D case 242 11.3.3. Stress concentration tensor 243 11.3.4. Comparison with other estimates 244 11.4. Mori–Tanaka estimates of effective compliance 244 11.4.1. Opened cracks 246 11.4.2. Closed cracks 246 11.5. Appendix: algebra for transverse isotropy and applications 246 Chapter 12. Bounds 251 12.1. The energy definition of the homogenized stiffness 252 12.2. Hashin–Shtrikman’s bound 255 12.2.1. Hashin–Shtrikman variational principle 255 12.2.2. Piecewise constant polarization field 259 12.2.3. Random microstructures 261 12.2.4. Application of the Ponte-Castaneda and Willis (PCW) bound to microcracked media 270 Chapter 13. Micromechanics-based Damage Constitutive Law and Application 273 13.1. Formulation of damage constitutive law 273 13.1.1. Description of damage level by a single scalar variable 274 13.1.2. Extension to multiple cracks 276 13.2. Some remarks concerning the loss of uniqueness of the mechanical response in relation to damage 277 13.3. Mechanical fields and damage in a hollow sphere subjected to traction 280 13.3.1. General features 280 13.3.2. Case of damage model based on the dilute estimate 284 13.3.3. Complete solution in the case of the damage model based on PCW estimate 285 13.4. Stability of the solution to damage evolution in a hollow sphere 296 13.4.1. The MT damage model 298 13.4.2. The general damage model [13.44] 300 Bibliography 305 Index 309

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Book SynopsisApplied RVE Reconstruction and Homogenization of Heterogeneous Materials Statistical correlation functions are a well-known class of statistical descriptors that can be used to describe the morphology and the microstructure-properties relationship. A comprehensive study has been performed for the use of these correlation functions for the reconstruction and homogenization in nano­composite materials. Correlation functions are measured from different techniques such as microscopy (SEM or TEM), small angle X-ray scattering (SAXS) and can be generated through Monte Carlo simulations. In this book, different experimental techniques such as SAXS and image processing are presented, which are used to measure two-point correlation function correlation for multi-phase polymer composites. Higher order correlation functions must be calculated or measured to increase the precision of the statistical continuum approach. To achieve this aim, a new approximation methodology is utilized to obtain N-point correlation functions for multiphase heterogeneous materials. The two-point functions measured by different techniques have been exploited to reconstruct the microstructure of heterogeneous media. Statistical continuum theory is used to predict the effective thermal conductivity and elastic modulus of polymer composites. N-point probability functions as statistical descriptors of inclusions have been exploited to solve strong contrast homogenization for effective thermal conductivity and elastic modulus properties of heterogeneous materials. Finally, reconstructed microstructure is used to calculate effective properties and damage modeling of heterogeneous materials.Table of ContentsPreface ix Introduction xiii Chapter 1 Literature Survey 1 1.1 Random heterogeneous material 1 1.2 Two-point probability functions 2 1.3 Two-point cluster functions 4 1.4 Lineal-path function 4 1.5 Reconstruction 4 1.5.1 X-ray computed tomography (experimental) 4 1.5.2 X-ray computed tomography (applications to nanocomposites) 6 1.5.3 FIB/SEM (experimental) 6 1.5.4 Reconstruction using statistical descriptor (numerical) 10 1.6 Homogenization methods for effective properties 11 1.7 Assumption of statistical continuum mechanics 12 1.8 Representative volume element 13 Chapter 2 Calculation of Two-Point Correlation Functions 15 2.1 Introduction 15 2.2 Monte Carlo calculation of TPCF 17 2.3 Two-point correlation functions of eigen microstructure 19 2.4 Calculation of two-point correlation functions using SAXS or SANS data 21 2.4.1 Case study for structural characterization using SAXS data 24 2.5 Necessary conditions for two-point correlation functions 28 2.6 Approximation of two-point correlation functions 30 2.6.1 Examination of the necessary conditions for the proposed estimation 34 2.6.2 Case study for the approximation of a TPCF 39 2.7 Conclusion 42 Chapter 3 Approximate Solution for N-Point Correlation Functions for Heterogeneous Materials 43 3.1 Introduction 43 3.2 Approximation of three-point correlation functions 45 3.2.1 Decomposition of higher order statistics 45 3.2.2 Decomposition of two-point correlation functions 46 3.2.3 Decomposition of three-point correlation functions 47 3.3 Approximation of four-point correlation functions 51 3.4 Approximation of N-point correlation functions 56 3.5 Results 60 3.5.1 Computational verification 60 3.5.2 Experimental validation 62 3.6 Conclusions 66 Chapter 4 Reconstruction of Heterogeneous Materials Using Two-Point Correlation Functions 67 4.1 Introduction 67 4.2 Monte Carlo reconstruction methodology 69 4.2.1 3D cell generation 72 4.2.2 Cell distribution 75 4.2.3 Cell growth 77 4.2.4 Optimization of the statistical correlation functions 79 4.2.5 Percolation 79 4.2.6 Three-phase solid oxide fuel cell anode microstructure 81 4.2.7 Reconstruction of multiphase heterogeneous materials 82 4.3 Reconstruction procedure using the simulated annealing (SA) algorithm 86 4.4 Phase recovery algorithm 91 4.5 3D reconstruction of non-eigen microstructure using correlation functions 96 4.5.1 Microstructure reconstruction using Monte Carlo methodology 96 4.5.2 Sample production 97 4.5.3 Monte Carlo calculation of a two-point correlation function 98 4.5.4 Microstructure optimization 99 4.5.5 Results and discussion 99 4.6 Conclusion 101 Chapter 5 Homogenization of Mechanical and Thermal Behavior of Nanocomposites Using Statistical Correlation Functions: Application to Nanoclay-based Polymer Nanocomposites 103 5.1 Introduction 103 5.2 Modified strong-contrast approach for anisotropic stiffness tensor of multiphase heterogeneous materials 104 5.3 Strong-contrast approach to effective thermal conductivity of multiphase heterogeneous materials 112 5.4 Simulation and experimental verification 117 5.4.1 Computer-generated model 118 5.4.2 Thermal conductivity 120 5.4.3 Mechanical model 122 5.4.4 Experimental part 125 5.5 Results and discussion 127 5.5.1 Thermal conductivity 127 5.5.2 Thermo-mechanical properties 128 5.6 Conclusion 130 Chapter 6 Homogenization of Reconstructed RVE 133 6.1 Introduction 133 6.2 Finite element homogenization of the reconstructed RVEs 134 6.2.1 Reconstruction of FIB-SEM RVEs 134 6.2.2 Finite element analysis of RVEs 138 6.3 Finite element homogenization of the statistical reconstructed RVEs 141 6.3.1 FEM analysis of reconstruction RVE using statistical correlation functions 141 6.3.2 Finite element analysis of RVEs 143 6.4 FEM analysis of debonding-induced damage model for polymer composites 149 6.4.1 Representative volume element (RVE) 150 6.4.2 Cohesive zone model 152 6.4.3 Material behavior and FE simulation 157 6.4.4 The effect of the GNP’s volume fraction and aspect ratio in perfectly bonded nanocomposite 158 6.4.5 Comparing the effect of the GNP’s volume fraction and aspect ratio in perfectly bonded and cohesively bonded nanocomposites 160 6.4.6 The effect of the GNP’s aspect ratio and volume fraction in weakly bonded nanocomposite 163 6.5 Conclusion and future work 166 Appendices 169 Appendix A 171 Appendix B 175 Bibliography 179 Index 185

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Book SynopsisThis book addresses the steps needed to monitor health assessment systems and the anticipation of their failures: choice and location of sensors, data acquisition and processing, health assessment and prediction of the duration of residual useful life. The digital revolution and mechatronics foreshadowed the advent of the 4.0 industry where equipment has the ability to communicate. The ubiquity of sensors (300,000 sensors in the new generations of aircraft) produces a flood of data requiring us to give meaning to information and leads to the need for efficient processing and a relevant interpretation. The process of traceability and capitalization of data is a key element in the context of the evolution of the maintenance towards predictive strategies.Table of ContentsIntroduction ix Chapter 1. PHM and Predictive Maintenance 1 1.1. Anticipative maintenance and prognostics 1 1.1.1. New challenges and evolution of the maintenance function 1 1.1.2. Towards an anticipation of failure mechanisms 3 1.2. Prognostics and estimation of the remaining useful life (RUL) 5 1.2.1. What is it? Definition and measures of prognostics 5 1.2.2. How? Prognostic approaches 6 1.3. From data to decisions: the PHM process 9 1.3.1. Detection, diagnostics and prognostics 9 1.3.2. CBM Architecture and PHM process 10 1.4. Scope of the book 12 Chapter 2. Acquisition: From System to Data 15 2.1. Motivation and content 15 2.2. Critical components and physical parameters 16 2.2.1. Choice of critical components – general approach 16 2.2.2. Dependability analysis of the system and related tools 17 2.2.3. Physical parameters to be observed 19 2.3. Data acquisition and storage 20 2.3.1. Choice of sensors 22 2.3.2. Data acquisition 23 2.3.3. Preprocessing and data storage 24 2.4. Case study: toward the PHM of bearings 25 2.4.1. From the “train” system to the critical component “bearing” 25 2.4.2. Experimental platform Pronostia 26 2.4.3. Examples of obtained signals 30 2.5. Partial synthesis 30 Chapter 3. Processing: From Data to Health Indicators 33 3.1. Motivation and content 33 3.2. Feature extraction 35 3.2.1. Mapping approaches 35 3.2.2. Temporal and frequency features 36 3.2.3. Time–frequency features 38 3.3. Feature reduction/selection 48 3.3.1. Reduction of the feature space 48 3.3.2. Feature selection . 54 3.4. Construction of health indicators 62 3.4.1. An approach based on the Hilbert-Huang transform 62 3.4.2. Approach description and illustrative elements 62 3.5. Partial synthesis 63 Chapter 4. Health Assessment, Prognostics and Remaining Useful Life – Part A 67 4.1. Motivation and content 67 4.2. Features prediction by means of connectionist networks 69 4.2.1. Long-term connectionist predictive systems 69 4.2.2. Prediction by means of “fast” neural networks 77 4.2.3. Applications in PHM problems and discussion 84 4.3. Classification of states and RUL estimation 88 4.3.1. Health state assessment without a priori information about the data 88 4.3.2. Toward increased performances: S-MEFC algorithm 93 4.3.3. Dynamic thresholding procedure 95 4.4. Application and discussion 97 4.4.1. Tests data and protocol 97 4.4.2. Illustration of the dynamic thresholding procedure 101 4.4.3. Performances of the approach 104 4.5. Partial synthesis 105 Chapter 5. Health Assessment, Prognostics, and Remaining Useful Life – Part B 109 5.1. Motivation and object 109 5.2. Modeling and estimation of the health state 111 5.2.1. Fundamentals: the Hidden Markov Models (HMM) 111 5.2.2. Extension: mixture of Gaussians HMMs 117 5.2.3. State estimation by means of Dynamic Bayesian Networks 118 5.3. Behavior prediction and RUL estimation 124 5.3.1. Approach: Prognostics by means of DBNs 124 5.3.2. Learning of state sequences 124 5.3.3. Health state detection and RUL estimation 126 5.4. Application and discussion 129 5.4.1. Data and protocol of the tests 129 5.4.2. Health state identification 131 5.4.3. RUL estimation 133 5.5. Partial synthesis 135 Conclusion and Open Issues 137 Bibliography 143 Index 163

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Book SynopsisManufacturing industries strive to improve the quality and reliability of their products, while simultaneously reducing production costs. To do this, modernized work tools must be produced; this will enable a reduction in the duration of the product development cycle, optimization of product development procedures, and ultimately improvement in the productivity of design and manufacturing phases. Numerical simulations of forming processes are used to this end, and in this book various methods and models for forming processes (including stamping, hydroforming and additive manufacturing) are presented. The theoretical and numerical advances of these processes involving large deformation mechanics on the basis of large transformations are explored, in addition to the various techniques for optimization and calculation of reliability. The advances and techniques within this book will be of interest to professional engineers in the automotive, aerospace, defence and other industries, as well as graduates and undergraduates in these fields.Table of ContentsPreface xi Chapter 1. Forming Processes 1 1.1. Introduction& 1 1.2. Different processes 1 1.2.1. Smelting 2 1.2.2. Machining 3 1.2.3. Powder metallurgy 5 1.3. Hot and cold forming 6 1.3.1. Influence of the static parameters 9 1.3.2. Hydroforming 12 1.3.3. The limitations of the process 13 1.3.4. Deep drawing 14 1.4. Experimental characterization 14 1.5. Forming criteria 16 1.5.1. Influence of the structure of sheet metal 18 1.5.2. Physical strain mechanisms 20 1.5.3. Different criteria 21 Chapter 2. Contact and Large Deformation Mechanics 23 2.1. Introduction 23 2.2. Large transformation kinematics 23 2.2.1. Kinematics of the problem in spatial coordinates 24 2.3. Transformation gradient 25 2.4. Strain measurements 26 2.4.1. Polar decomposition of F 26 2.4.2. Strain rate tensor 27 2.4.3. Canonical decomposition of F 28 2.4.4. Kinematics of the problem in convective coordinates 28 2.4.5. Transformation tensor 29 2.4.6. Strain rate measures 32 2.4.7. Strain tensor 35 2.5. Constitutive relations 36 2.5.1. Large elastoplastic transformations 38 2.5.2. Kinematic decomposition of the transformation 41 2.6. Incremental behavioral problem 42 2.6.1. Stress incrementation 42 2.6.2. Strain incrementation 44 2.6.3. Solution of the behavior problem 46 2.7. Definition of the P.V.W. in major transformations 49 2.7.1. Equilibrium equations 49 2.7.2. Definition of the P.V.W 50 2.7.3. Incremental formulation 51 2.8. Contact kinematics 52 2.8.1. Definition of the problem and notations 52 2.8.2. Contact formulation 53 2.8.3. Formulation of the friction problem 53 2.8.4. Friction laws 54 2.8.5. Coulomb's law 54 2.8.6. Tresca's law 55 Chapter 3. Stamping 57 3.1. Introduction 57 3.2. Forming limit curve 59 3.3. Stamping modeling: incremental problem 60 3.3.1. Modeling of sheet metal 61 3.3.2. Spatial discretization: finite elements method 62 3.3.3. Choice of sheet metal and finite element approximation 63 3.4. Modeling tools 64 3.4.1. Tool surface meshing into simple geometry elements 64 3.4.2. Analytical representation of tools 65 3.4.3. Bezier patches 65 3.5. Stamping numerical processing 72 3.5.1. Problem statement 73 3.5.2. The augmented Lagrangian method 75 3.6. Numerical simulations 79 3.6.1. Sollac test 81 Chapter 4. Hydroforming 83 4.1. Introduction 83 4.2. Hydroforming 85 4.2.1. Tube hydroforming 85 4.2.2. Sheet metal hydroforming 86 4.3. Plastic instabilities in hydroforming 87 4.3.1. Tube buckling 88 4.3.2. Wrinkling 90 4.3.3. Necking 91 4.3.4. Springback 92 4.4. Forming limit curve 92 4.5. Material characterization for hydroforming 94 4.5.1. Tensile testing 95 4.5.2. Bulge testing 95 4.6. Analytical modeling of a inflation test 97 4.6.1. Hill48 criterion in planar stresses 97 4.7. Numerical simulation 100 4.8. Mechanical characteristic of tube behavior 101 Chapter 5. Additive Manufacturing 105 5.1. Introduction 105 5.2. RP and stratoconception 107 5.3. Additive manufacturing definitions 109 5.4. Principle 113 5.4.1. Principle of powder bed laser sintering/melting 114 5.4.2. Principle of laser sintering/melting by projecting powder 116 5.5. Additive manufacturing in the IT-based development process 117 5.5.1. Concept "from the object to the object" 117 5.5.2. Key element of the IT development process 118 Chapter 6. Optimization and Reliability in Forming 121 6.1. Introduction 121 6.2. Different approaches to optimization processes 122 6.2.1. Limitations of the deterministic approaches 124 6.3. Characterization of forming processes by objective functions 125 6.4. Deterministic and probabilistic optimization of a T-shaped tube 126 6.4.1. Problem description 126 6.4.2. Choice of the objective function and definition of the stresses 127 6.4.3. Choice of the uncertain parameters 128 6.4.4. Choice of the objective function and the stresses 130 6.4.5. Deterministic formulation of the optimization problem 132 6.4.6. Probabilistic formulation of the optimization problem 133 6.4.7. Optima sensitivity to uncertainties 140 6.5. Deterministic and optimization-based reliability of a tube with two expansion regions 142 6.5.1. Problem description 142 6.5.2. Deterministic and reliabilist formulation of the optimization problem 147 6.6. Optimization-based reliability of circular sheet metal hydroforming 150 6.6.1. Problem description 150 6.6.2. Construction of the objective function and of the stresses 151 6.6.3. Effects diagram 151 6.6.4. Deterministic solution of the optimization problem 155 6.6.5. Reliabilist solution of the optimization problem 157 6.6.6. Effect of uncertainties on the optimal variables 159 6.7. Deterministic and robust optimization of a square plate 160 6.7.1. Robust resolution of the optimization problem 166 6.8. Optimization of thin sheet metal 168 Chapter 7. Application of Metamodels to Hydroforming 171 7.1. Introduction 171 7.2. Sources of uncertainty in forming 172 7.3. Failure criteria 173 7.3.1. Failure criteria for necking 174 7.3.2. Failure criteria for wrinkling 174 7.4. Evaluation strategy of the probability of failure 175 7.4.1. Finite element model and choice of uncertainty parameters 176 7.4.2. Identification of failure modes and definition of boundary states 180 7.4.3. Identification of elements and critical areas 181 7.5. Critical strains probabilistic characterization 185 7.5.1. Choice of numerical experimental design 186 7.5.2. Construction of metamodels 186 7.5.3. Validation and statistical analysis of metamodels 187 7.5.4. Fitting of distributions 187 7.6. Necking and wrinkling probabilistic study 193 7.7. Effects of the correlations on the probability of failure 196 7.7.1. Spatial estimation of the probability of failures 197 Chapter 8. Parameters Identification in Metal Forming 199 8.1. Introduction 199 8.2. Identification methods 199 8.2.1. Validation test 200 8.3. Welded tube hydroforming 203 8.3.1. Thin sheet metal hydroforming 205 Appendices 213 Appendix 1. Optimization in Mechanics 215 Appendix 2. Reliability in Mechanics 223 Appendix 3. Metamodels 233 Bibliography 243 Index 253

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Book SynopsisLeakage and emmission control is a critical function in process plant, industrial equipment, machinery, and transportation systems. This volume reflects many of the recent advances in sealing technology with topics including: tribology; static seals; and mechanical seals.Table of ContentsPart 1 Tribology: tribological behaviour of PTFE seal materials in sealing contact with steel and ceramic coatings; influence of the sealing surface characteristics on friction behaviour. Part 2 Dynamic seals - 1: the sealing mechanisms of rotary shaft seals with reference to the elastomer deformation in the contact zone; a study on the fluid-flow and the film-thickness of radial shaft seals using fluorescent microcapsule visualization and laser-induced fluorescent method; prediction of lip seal performance - an advanced FEA/interface iterative solver; material models for finite element analysis based on the example of rotary lip seals for pressure. Part 3 Modelling: gas pressure and leakage rate in static seals; cost-effective perfluoroelastomer sealing solutions for aggressive environments; increased confidence in sealing system design using FEA simulations; simulation of fluid seals by coupled fluid-solid-mechanical analysis. Part 4 Static seals: experience with bolted-flanged joints and the selection of gaskets to minimize fugitive emissions; fastener phobia in fluid sealing; an alternative to asbestos for high-temperature gasketting applications; the further development of a high-temperature sealing material based upon chemically exfoliated vermiculite; the use of serrated core metallic gaskets on air coolers. Part 5 Mechanical seals - 1: towards the universal mechanical seal for industrial pumps; development and application of double pulse gas-liquid face seals; condition monitoring of mechanical seals using actively generated ultrasonic waves; reactor coolant pump seal response to loss of cooling. Part 6 Dynamic seals - 2: optimal surface roughness of the shafts co-operating with oil lip seals; leakage of radial lip seals at large eccentricities; face packing seals - new opportunities for pump rotor hermetic sealing; study of sealing capability of magnetic fluid shaft seals. Part 7 Emissions: joint industry project on the measurement of fugitive emissions from valve stems; improved gland packings for control valves; fugitive emissions from VCM - PVC units - results of the ECVM survey; in-situ repair of double "O" ring seals on CO2 pressure boundaries. Part 8 Mechanical seals -2: the influence of the duty parameter G on the PV limit in mechancial seals; an advanced test bench for mechanical face seals testing; development and tests of the advance wear-resistant mechanical face seals; analysis of lubricant regime transition, experimentally observed in liquid face seals, using an analytical model for thermoelastic face distortion. Part 9 Non-contacting: a model of zero pressure differences and zero leakage for non-contacting spiral groove liquid face seals; determination of optimal parameters of labyrinth-screw seals and pumps; advanced aerostatic dry gas seal; influence of centrifugal growth of runner on floating bushing oil seal performance and compressor stability using finite element methods.

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Book SynopsisVibrations in Rotating Machinery provides an opportunity for the reader to be informed of new developments and industrial applications of current trechnology relevant to the vibration of machines and assemblies.Table of ContentsBladed systems; balancing; case studies; surface influences; rub; impacts and rub; identification; active control; bearings and rotors; rotors; bearings; bearing and seals; condition monitoring and cracked rotors; condition monitoring; theoretical considerations.

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Book SynopsisStandardized processing routes for PM fabrication Powder Metallurgy in Design: Wear, Corrosion and Fatigue Resistance is an essential resource for anyone in the field. Powder metallurgy allows engineers to control the microstructure of the metal, resulting in materials more suitable for the fabrication of unique parts with unique properties — yet the process of formulating these metals is itself unique. This book standardizes and codifies the necessary processing routes, and helps engineers incorporate the potential of these products into the design stage of a project.Table of ContentsPowder metallurgy - the process and possibilities; design powder metallurgy for adhesive wear resistance; designing with tungsten carbide for erosive/corrosive applications; tungsten carbide for abrasion resistant aplications; designign with powder metallurgy for increased fatigue life; using powder metallury for friction metals.

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Book SynopsisFlow-Induced Vibration of Power and Process Plant Components is an indispensable, single source of information on the most common flow-induced vibration problems in power and process plant components. Based on the author’s own experience that most errors in engineering analysis come from confusions in the units, the book begins with a short chapter on units and dimensions. It also provides step-by-step examples in dual US and SI units, leading to the final objective of design analysis, problem solving, diagnosis, and trouble shooting covering: Fundamentals of vibration; Acoustics and structural dynamics; Vibration of structures in quiescent fluids; Vortex-induced vibration; Turbulence-induced vibration; Impact, fatigue, and wear caused by flowinduced vibration; Acoustically induced vibration; Signal analysis and diagnostic techniques. CONTENTS INCLUDE: The kinematics of vibration and acoustics Fundamentals of structural dynamics Vortex-induced vibration Fluid-elastic instability of tube bundles Axial and leakage-flow-induced vibrations Impact, fatigue and wear Signal analysis and diagnostic techniques Table of ContentsUnits and dimensions; the kinematics of vibration and acoustics; fundamentals of structural dynamics; vibration of structures in quiescent fluid 1 - the hydrodynamic mass; vibration of structures in quiescent fluids 2 - simplified methods; vortex-induced vibration; fluid-elastic instability of tube bundles; turbulence-induced vibration in parallel flow; turbulence-induced vibration in cross-flow; axial and leakage-flow induced vibrations; impact, fatigue and wear; acoustically induced vibration and noise; signal analysis and diagnostic techniques.

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Book SynopsisNow available in a new improved format, this second edition is completely revised and updated. An Introductory Guide to Flow Measurement is an indispensable guide for the busy practising engineer. It provides a ready source of information on flowmeters, their operation, installation, and relative advantages and disadvantages in different applications. This revised edition retains the succinct style of the original, with plenty of clear line diagrams and shading to highlight key points, it is comprehensive and easy-to-use. The material is based on the author’s own lectures at Cranfield Institute of Technology, UK, but incorporates lessons learned through using the first edition as a teaching tool during the 13 years since its first publication. It aims to transmit as much information as possible, as efficiently as possible, in as short a time as possible. Essential reading for any engineer faced with a flow measurement problem – this book will enable the reader to assess advice received from manufacturers and contribute to discussions with experts. Existing and new readers alike will welcome this updated version of the well established and highly regarded Introductory Guide to Flow Measurement. Key areas considered include: Accuracy; flow behavior, and fluid parameters Calibration techniques Selection Momentum flowmeters Volumetric flowmeters Mass flowmeters Probes and tracers Recent developments and future trends Table of ContentsPart 1 Introduction: accuracy; flowmeter systems; flow in pipes; effect on flowmeters; essential equations of flow; fluid parameters; multiphase flows. Part 2 Calibration: datum conditions; steady flow; calibration rigs for liquids; calibration rigs for gases; master meters; site calibrations; general comments. Part 3 Selection: considerations in selecting a flowmeter; nature of the fluid to be metered; flowmeter constraints; environment; special effects; price; choosing. Part 4 Momentum flowmeters: orifice plate meter; Venturi meter; special orifice plates and flow nozzles; critical nozzle (sonic nozzle); other differential pressure devices; target meter (drag plate); variable area, Rotameter (R) or float-in-tube meter; momentum-sensing flowmeters - general comments. Part 5 Volumetric flowmeters: positive displacement meters; turbine meters; oscillatory meters; electromagnetic meters; ultrasonic meters. Part 6 Mass flowmeters: introduction; thermal mass flow measurement; angular momentum fuel flowmeter; Coriolis flowmeters. Part 7 Probes and tracers: probes; averaging pitot; tracers; conclusions. Part 8 Recent developments and likely future trends in flow measurement: instruments; meters for multiphase flow; developing technologies; manufacture and management; conclusions.

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Book SynopsisA collection of papers from an IMechE event held in February 2004. Materials are critical to the safety, reliability, performance and total life cycle costs of machines, and are therefore of great importance to both users and suppliers. The papers in this volume review: The increasing availability and improvements of superior materials over the last decade, moving from niche markets to a wide field of applications The advancement of materials from the experimental stage to the point where they can make real contributions to machine life and reliability New developing or nontraditional materials which have real potential for future reduction in life cycle costs of fluid machinery. Advanced Materials for Fluid Machinery will be of value to all those involved in materials for fluid machinery, including manufacturers and users, material suppliers, refurbishers, contractors, consultants, materials specialists and researchers.Table of ContentsS965/001/2004 Developments in the use of stainless steels for pumps and valves R Francis and L M Phillips 1; S965/002/2004 A cavitation-resistant casting alloy for pumps - status after ten years' commercial use C McCaul 15; S965/003/2004 Applications of advanced materials in centrifugal pumps B Germaine, P Meuter, and W Duchting 29; S695/004/2004 Using polymer composite wear materials in centrifugal pumps S A Smith 47; S965/005/2004 Centrifugal compressor redesign utilizing carbon fibre composite impellers D A Sarin, O A Majamaki, J K Kuokkanen, and A G Sheard 67; S965/006/2004 Chemically formed ceramic coatings S R Gibson 83; S965/007/2004 Meeting the challenges in pump durability by advanced surface engineering A Neville, V A D Souza, L M Phillips, P A Smith, P Gourdji, and H W Wang 95; S965/008/2004 Challenges of living with erosion-corrosion R J K Wood 113; S965/009/2004 Laser Engineered Net Shaping[trademark] - technology, applications, and opportunities in fluid machinery M Hedges 133; Authors' Index 145

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Book SynopsisThis book serves as a practical guide for applications of X-ray fluorescence spectrometry, a nondestructive elemental analysis technique, to the study and understanding of archaeology. Descriptions of XRF theory and instrumentation and an introduction to field applications and practical aspects of archaeology provide new users to XRF and/or new to archaeology with a solid foundation on which to base further study. Considering recent trends within field archaeology, information specific to portable instrumentation also is provided. Discussions of qualitative and quantitative approaches and applications of statistical methods relate back to types of archaeological questions answerable through XRF analysis. Numerous examples, figures, and spectra from the authors' field work are provided including chapters specific to pigments, ceramics, glass, construction materials, and metallurgical materials.

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Book SynopsisSolidification is one of the oldest processes for producing complex shapes for applications ranging from art to industry, and remains as one of the most important commercial processes for many materials. Since the 1980s, numerous fundamental developments in the understanding of solidification processes and microstructure formation have come from both analytical theories and the application of computational techniques using commonly available powerful computers. This book integrates these developments in a comprehensive volume that also presents and places them in the context of more classical theories. This second edition highlights the key concepts within each chapter to help guide the reader through the most important aspects of the topics. The figures are now in color, in order to improve the visualization of phenomena and concepts. Recent important developments in the field since the first edition was published have also been added. The three-part text is aimed at graduate and professional engineers. The first part, Fundamentals and Macroscale Phenomena, presents the thermodynamics of solutions and then builds on that subject to motivate and describe equilibrium phase diagrams. Transport phenomena are discussed next, focusing on the issues of most importance to liquid-solid phase transformations, then moving on to describing in detail both analytical and numerical approaches to solving such problems. The second part, Microstructure, employs these fundamental concepts for the treatment of nucleation, dendritic growth, microsegregation, eutectic and peritectic solidification, and microstructure competition. This part concludes with a chapter describing the coupling of macro- and microscopic phenomena in microstructure development. The third and final part describes various types of Defects that may occur, with emphasis on porosity, hot tearing and macrosegregation, presented using the modeling tools and microstructure descriptions developed earlier.Table of ContentsOverview Introduction Solidification processes References PART 1 FUNDAMENTALS AND MACROSCALE PHENOMENA Thermodynamics Introduction Thermodynamics of unary systems Binary alloys Departure from equilibrium Exercises References Phase diagrams Motivation Binary systems Ternary systems Exercises References Balance Equations Introduction Mass balance Momentum balance Energy balance Solute balance in multicomponent systems Scaling Exercises References Analytical solutions for solidification Introduction Solidification in a superheated melt Solidification in an undercooled melt The effect of curvature Exercises References Numerical methods for solidification Introduction Heat conduction without phase change Heat conduction with phase change Fluid flow Optimization and inverse methods Exercises References PART II MICROSTRUCTURE Nucleation Introduction Homogeneous nucleation Heterogeneous nucleation Mechanisms for grain refinement Exercises References Dendritic growth Introduction Free growth Constrained growth Growth of a needle crystal Convection and dendritic growth Phase-field methods Exercises References Eutectics, peritectics and microstructure selection Introduction Eutectics Peritectics Phase selection and coupled zone Exercises References Microsegregation and homogenization Introduction 1-D microsegregation models for binary alloys Homogenization and solution treatment Multicomponent alloys Exercises References Macro- and microstructures Introduction Equiaxed grains growing in a uniform temperature field Grains nucleating and growing in a thermal gradient Columnar grains Columnar-to-Equiaxed Transition Micro-macroscopic models Exercises References PART III DEFECTS Porosity Introduction Governing equations Interdendritic fluid flow and pressure drop Thermodynamics of gases in solution Nucleation and growth of pores Boundary conditions Application of the concepts Exercises References Deformation during solidification and hot tearing Introduction Thermomechanics of castings Deformation of the mushy zone Hot tearing Hot tearing criteria and models Exercises References Macrosegregation Introduction Macrosegregation during planar front solidification Composition field and governing equations Macrosegregation induced by solidification shrinkage Macrosegragation induced by fluid flow Macrosegregation induced by solid movement Exercises References

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Book SynopsisThis indispensable handbook provides comprehensive coverage of the current state-of-the-art in inorganic, organic, and composite aerogels – from synthesis and characterization to cutting-edge applications and their potential market impact. Built upon Springer’s successful Aerogels Handbook published in 2011, this handbook features extensive revisions and timely updates, reflecting the changes in this fast-growing field. Aerogels are the lightest solids known to man. Up to 1000 times lighter than glass and with a density only four times that of air, they possess extraordinarily high thermal, electrical, and acoustic insulation properties, and boast numerous entries in Guinness World Records. Originally based on silica, R&D efforts have extended this class of materials to incorporate non-silicate inorganic oxides, natural and synthetic organic polymers, carbon, metal, and ceramic materials. Composite systems involving polymer-crosslinked aerogels and interpenetrating hybrid networks have been developed and exhibit remarkable mechanical strength and flexibility. Even more exotic aerogels based on clays, chalcogenides, phosphides, quantum dots, and biopolymers such as chitosan are opening new applications for the construction, transportation, energy, defense and healthcare industries. Applications in electronics, chemistry, mechanics, engineering, energy production and storage, sensors, medicine, nanotechnology, military and aerospace, oil and gas recovery, thermal insulation, and household uses are being developed.Readers of this fully updated and expanded edition will find an exhaustive source for all aerogel materials known today, their fabrication, upscaling aspects, physical and chemical properties, and the most recent advances towards applications and commercial use. This key reference is essential reading for a combined audience of graduate students, academic researchers, and industry professionals.Table of ContentsPART A: Unit Operations: Processing Steps used in Aerogel Science.- Sol-Gel.- Solvent Exchange and Functionalization.- Supercritical drying of aerogels: theory and practice.- Freeze drying.- Postprocessing.- PART B: Characterization.- Structural Characterization of Aerogels.- Mechanical Characterization of Aerogels.- Thermal Properties of Aerogels.- Permeability of Aerogels.- Simulation and Modeling of Aerogels Using Atomistic and Mesoscale Methods.- Part C: Oxide Based Aerogels.- SiO2 aerogels.- Hydrophobic Silica Aerogels.- Superhydrophobic and Flexible Aerogels and Xerogels derived from organosilane precursors.- Sodium Silicate-based Aerogels.- A Robust Approach to Inorganic Aerogels: The Use of Epoxides in Sol-Gel Synthesis.- High Temperature Oxide Aerogels.- Preparation of TiO2 Aerogels-Like Materials under Ambient Pressure.- ZrO2 Aerogels.- Part D: Synthetic Polymer Aerogels.- Phenolic-type aerogels and derived carbons: the paradigms of resorcinol-formaldehyde and polybenzoxazine chemistries.- Isocyanate-derived aerogels and applications.- Aerogels from Engineering Polymers: Polyimide and Polyamide Aerogels.- Part E: Biopolymer Aerogels.- Cellulose Aerogels: Monoliths, Beads and Fibers.- Silica Biopolymer Aerogel Nanocomposites.- Polysaccharide (non-cellulosic) aerogels.- Nanocellulose Aerogels.- Potential of anisotropic cellulosic aerogels.- Part F: Organic-Inorganic Hybrid Aerogels.- Polymer Crosslinked Aerogels.- Improving Elastic Properties of Polymer-Reinforced Aerogels.- Aerogels containing metal, alloy and oxide nanoparticles embedded into dielectric matrices.- Tuning the physical properties of aerogels by spatially selective modification.- Aerogels through ultrasonically-assisted synthesis.- Part G: Carbon-Based Aerogels.- Preparation and Application of Carbon Aerogels.- Nanocarbons: Diamond, Fullerenes, Nanotubes and Graphene Aerogels.- Nanotube Aerogels made through Elastic Smoke.- Part H: Frontier / Emerging Aerogels.- Chalcogenide Aerogels.- Fluorinated and Fluoride Inorganic Aerogels.- Nanoparticle-Based Inorganic Aerogels.- Metal aerogels.- Noble Metal Aerogels.- Nanoporous metal foams made by combustion synthesis.- Interpenetrating phenolic/oxide networks and carbothermal synthesis of metallic aerogels as energetic materials.- Synthesis of largescale nanoporous metallic networks by PVD.- Part I: Applications.- Aerogels and Sol-Gel Composites as Nanostructured Energetic Materials.- Aerogel as thermal super-insulating materials: an overview.- Aerogels as platforms for chemical sensors.- Aerogels for Electrochemical energy storage applications.- Transparent Silica Aerogel Blocks for High-Energy Physics Research.- Aerogels for fusion target fabrication.- Porous Glasses, Binary Glasses and Composite Glasses from Aerogels.- Aerogels for Environmental Applications.- Aerogels for Pollution Mitigation.- Application of Aerogels in Optical Devices.- Biomedical Applications of Aerogels.- in vivo Biomedical Applications of Aerogels.- Pharmaceutical Applications of Aerogels.- Applications of Aerogels in Space Exploration.- Airbone Ultrasonic Transducer.- Aerogels for foundry applications.- Aer()sculpture: A Free-Dimensional Space Art.- Aerogels from industrial waste.- Part J: Commercial Products and Industry Overview.- Industry overview.- Part K: Recipes and Designs.- Recipes and Designs.- Subject index.- Glossary, Acronyms and Abbreviations.

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Book SynopsisThis book examines recent developments in inert anodes for aluminum electrolysis. It describes the composition and application of the most promising metal ceramic inert anode materials and nickel-oxide nanotechnology in the aluminum industry. The volume addresses concepts, analysis, properties, conductivity and corrosion, microstructure and microanalysis, and machinability of inert anodes for aluminum electrolysis. The book will be valuable to the aluminum industry, where inert anodes are having a profound impact in creating more energy saving, greener, and more functional aluminum materials in high-strength and high-temperature applications.Table of ContentsResearch background of inert anodes for aluminum electrolysis.- Nanomaterials and Nanocermets.- Nancermet anodes for aluminum electrolysis.- Metallographic analysis of cermet materials.- X-ray diffraction analysis of nanocermets.- Bulk density, apparent porosity, and density of nanocermets.- Conductivity of nanocermets.- Corrosion resistance of nanocermet.- Post processing of samples.- Characterization of specimen structure of nanocermets.- Measurement of mechanical properties of NiFe2O4 nanocermet.- Microstructure and microanalysis of cermet materials.- Optimization and machinability of nanocermets for aluminum electrolysis.

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