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.