Table of Contents
Preface xiii
Chapter 1 Introduction to Zinc 1
Element 30 Zn – Spelter 1
The Zinc Atom 9
History 11
Zinc Mineral Forms 17
Zinc in Art 18
Zinc as an Architectural Metal 24
Health and Hygiene 28
The Enigmatic Metal 31
Chapter 2 Zinc Alloys 33
Introduction 33
Alloying Descriptions 34
Ingot Alloys 36
Zinc Alloys – Rolled Forms 39
Zinc Alloys Used in Architecture 41
Wrought Zinc Alloys 44
Architectural Rolled Zinc 47
Forged and Extruded Zinc Alloys 53
Cast Zinc Alloys 55
Slush Casting 56
Zinc Die Casting 58
Gravity Cast Alloys 59
Kirksite 62
Chapter 3 Finishes 63
Introduction 63
Appearance among Metals 65
Mill Finishes 68
Natural Zinc Color 68
Mechanical Finishes 71
Mechanically Rolled Textures 72
Preweathered Zinc Surface 73
Clear Coating with Pigmentation 77
Blackened Zinc 77
Custom Patina Finish 79
Dark Variegated Patinas on Zinc 80
Zinc Oxide Patinas 87
Zinc Iridescent Patina 93
Galvanized Zinc Surfaces 93
Galvanized Steel Structural Shapes 99
Darkening Galvanized Steel 100
Zinc Phosphate Coatings on Galvanized Steel 101
Zinc Fabric 102
Other Methods of Applying Zinc to Steel 103
Zinc Anodizing 104
Chapter 4 Expectations 105
Introduction 105
Natural Finish on Thin Sheet Material 107
Natural Finish on Thick Plate Material 109
Natural Finish on Cast Surface 110
Preweathered Finish 113
Preweathered with Added Pigmentation 119
Expectations – Preweathered Surface 120
Blackened Zinc 121
Color Matching 122
Custom Patinas 124
Flatness and Visual Distortion 131
Creep 135
Galvanized Surface 138
Darkened Galvanized Steel 142
Chapter 5 Available Forms 145
Introduction 145
Wrought Forms of Zinc 148
Plate 152
Sheet and Coil 153
Zinc Foil 158
Extrusion 158
Tube and Pipe 159
Wire 160
Rod 160
Wire Mesh 160
Expanded Metal 160
Perforated Zinc 162
Textured Zinc Sheet 163
Zinc Ornamentation 165
Cast 166
Slush Cast 167
Die Cast 167
Sand Cast 169
Zinc Powder 171
Chapter 6 Fabrication 173
Working with Zinc 173
Storage and Handling 174
Cutting Zinc 177
Shearing and Blanking 177
Saw Cutting 177
Laser 178
Plasma 179
Waterjet 179
Punching / Perforating / Bumping 180
Forming and Bending 184
Grain Direction and Anisotropy 185
Temperature Effect on Forming 187
Brake Forming 187
V-Cutting 191
Roll Forming 191
Superplastic Forming 192
Forging 193
Extrusion 194
Machining 194
Soldering 195
Welding 197
Fusion Stud Welding 199
Resistant Welding of Zinc 201
Expansion / Contraction 202
Bolting and Fastening 204
Thermal Spray 206
Hot-Dipped Galvanizing 206
Casting 208
Die Casting 210
Slush Casting 211
Permanent Mold Casting 212
Sand Casting 212
Plaster Mold Casting 212
Spin Casting 212
Chapter 7 Corrosion 215
Introduction 215
Zinc as a Protective Coating 216
Galvanized Steel 218
Zinc Alloy Coatings on Steel 219
Zinc Powder in Paint Coatings 220
Sherardizing 221
Thermal Spray 221
Zinc Anodes 222
Battery 222
When Zinc Does Not Protect Steel 224
Zinc Corrosion 225
Interior Exposures 227
Exterior Exposures 228
Sheltered Exterior Surfaces 230
Uniform Corrosion 235
Underside Corrosion 236
Wet Storage Stain 237
Galvanic Corrosion 239
Determining Factors for Galvanic Corrosion 242
Difference in Electro-Potential 243
Geometric Relationship 243
Distance 244
Electrolyte Effects 244
Temperature Effects 245
Pitting Corrosion 246
Intergranular Corrosion 248
Stress Corrosion Cracking 248
Zinc Artifacts and Statues 249
Deicing Salts 251
Chlorides 252
Fertilizer 253
Saponification 254
Corrosive Substances in Proximity 254
Chapter 8 Maintaining the Zinc Surface 257
Introduction 257
Zinc Surfaces 258
Why a Maintenance Procedure 260
Develop a Maintenance Strategy 260
Restoring the Preweathered Appearance 264
Effects of Different Environments 266
Physical Cleanliness 267
Chemical Cleanliness 278
Mechanical Cleanliness 292
Galvanized Steel Surfaces 296
Appendix A Brand Names 301
Appendix B Select Specifications for Zinc 303
References 305
Index 307
