Corrosion Science and Technology

✍ Scribed by Cheryl M. Burgess

• Publisher: CRC-Press
• Year: 1997
• Tongue: English
• Leaves: 391
• Series: Materials Science & Technology
• Edition: 1
• Category: Library

✦ Synopsis

Although they often appear to be permanent, metals are unstable in their service environments and are susceptible to degradation by corrosion. Corrosion occurs when protective mechanisms have been overlooked, break down, or have been exhausted, leaving the metal vulnerable to attack by hostile environments. Control of corrosion is essential in a wide variety of industries. It is of concern to materials scientists and engineers, yet both students and professionals often cannot assimilate the information they need in typical corrosion-related literature because they do not have the specialized background these sources assume. Corrosion Science and Technology clarifies this important background material and guides readers in its practical application.This text integrates the chemical, electrochemical, and metallurgical aspects of corrosion control for application in typical contemporary technologies with economical use of resources. The structures of water, oxides, and metals are examined to identify the interactions by which metals can corrode in natural and relevant artificial environments. The book describes the characteristics of metals and alloys often specified for corrosion-resistant service, and discusses the relative merits of various protective measures and the strategies available to control corrosion. Corrosion Science and Technology profiles aviation, automobile manufacture, food processing, and building construction to show how these sample industries currently address corrosion issues.Written from long experience of both teaching and practice in the field, this book includes explanations of scientific principles and real world applications and case histories. Extensive information on additional corrosion-related literature is provided to guide readers to sources of more specific information. Corrosion Science and Technology gives readers a solid foundation on which to understand and apply corrosion control measures and to comprehend and use information from other sources.

✦ Table of Contents

CORROSION SCIENCE and TECHNOLOGY......Page 4
Contents......Page 6
Preface......Page 13
The Authors......Page 15
Acknowledgments......Page 16
1.1.1 Corrosion as a System Characteristic......Page 17
1.1.2 The Electrochemical Origin of Corrosion......Page 18
1.1.3 Stimulated Local Corrosion......Page 19
1.2.1 Protective Oxides......Page 20
1.4.1 Passivity......Page 21
1.4.3 Cathodic Protection......Page 22
1.4.6 Criteria for Corrosion Failure......Page 23
1.4.7 Material Selection......Page 24
1.5.1 Ions and Ionic Equations......Page 26
1.5.2 Partial Reactions......Page 27
Active Dissolution of Iron with Oxygen Absorption......Page 28
Passivity of Iron in Alkaline Water......Page 29
Further Reading......Page 30
2.1.1 Phases......Page 31
2.1.1.1 Crystalline Solids......Page 32
The Face-Centered Cubic (FCC) Lattice......Page 33
The Simple Cubic Lattice......Page 35
2.1.1.2 Liquids......Page 36
2.1.2 The Role of Electrons in Bonding......Page 37
2.1.2.1 Atomic Orbitals......Page 38
2.1.2.2 Molecular Orbitals and Bonding of Atoms......Page 40
2.1.3 The Concept of Activity......Page 42
2.2.1 The Nature of Water......Page 43
2.2.3 Liquid Water......Page 44
2.2.3.1 Hydrogen Bonding......Page 45
2.2.3.2 Dielectric constant......Page 46
2.2.4 Autodissociation and pH of Aqueous Solutions......Page 47
2.2.5 The pH Scale......Page 48
2.2.6 Foreign Ions in Solution......Page 49
2.2.7 Ion Mobility......Page 51
2.2.8 Structures of Water and Ionic Solutions at Metal Surfaces......Page 53
2.2.9.1 Rainwater......Page 54
Example 2:pH of rainwater......Page 55
Example 3:pH of a representative hard water......Page 57
Solution:......Page 58
2.3 The Structures of Metal Oxides......Page 59
2.3.1 Electronegativity......Page 60
2.3.2 Partial Ionic Character of Metal Oxides......Page 61
2.3.3 Oxide Crystal Structures......Page 62
2.3.3.4 Spinel Structures......Page 64
2.3.4 Conduction and Valence Electron Energy Bands......Page 65
2.3.5 The Origins of Lattice Defects in Metal Oxides......Page 66
2.3.5.1 General Approach......Page 67
2.3.5.2 Configurational Entropy of Atoms or Ions on a Lattice......Page 68
2.3.5.3 Equilibrium Number of Defects......Page 69
2.3.5.4 Natures of Defects in Oxide Lattices......Page 70
2.3.6 Classification of Oxides by Defect Type......Page 71
2.3.6.2 Cation Excess Oxides......Page 72
2.3.6.3 Cation Deficit Oxides......Page 73
2.3.6.4 Anion Deficit Oxides......Page 74
2.4 The Structures of Metals......Page 75
Contraction During Solidification......Page 83
Texture......Page 84
2.4.1 The Metallic Bond......Page 76
2.4.3 Phase Equilibria......Page 77
2.4.3.1 Solid Solutions......Page 78
2.4.3.2 Eutectic Transformations......Page 79
2.4.3.3 Peritectic Transformations......Page 80
2.4.3.6 Real systems......Page 81
Further Reading......Page 85
3.1.1.1 Oxidation States......Page 86
3.1.1.2 Electrodes......Page 88
3.1.2 Equilibria at Electrodes and the Nernst Equation......Page 89
3.1.3 Standard State for Activities of Ions in Solution......Page 90
3.1.4.1 Convention for Representing Electrodes at Equilibrium......Page 91
3.1.4.3 The Standard Hydrogen Electrode......Page 92
Solution:......Page 94
3.1.5.1 Principle and Purpose......Page 95
Selection of Species and Reactions:......Page 96
Calculations:......Page 97
Plotting Lines on the Diagram:......Page 99
The Complete Diagram:......Page 100
3.1.5.3 The Domain of Stability for Water......Page 101
3.1.5.4 Application of Pourbaix Diagrams to Corrosion Problems......Page 102
3.1.5.5 Pourbaix (Potential-pH) Diagrams for Some Common Metals......Page 103
Solution:......Page 106
The Solid Oxides Cu2O and CuO:......Page 108
3.1.5.6 Limitations of Pourbaix Diagrams......Page 109
3.2 Kinetics of Aqueous Corrosion......Page 110
3.2.1 Kinetic View of Equilibrium at an Electrode......Page 111
3.2.2.1 Activation Polarization......Page 112
The Symmetry Factor, a......Page 114
3.2.2.2 Concentration Polarization......Page 115
3.2.2.4 The Hydrogen Evolution Reaction and Hydrogen Overpotential......Page 117
Solution:......Page 118
3.2.3 Polarization Characteristics and Corrosion Velocities......Page 120
3.2.3.1 Corrosion Velocity Diagrams......Page 121
Example 9......Page 122
Solution:......Page 123
3.2.4.1 Spontaneous Passivation......Page 125
3.2.4.3 Theories of Passivation......Page 126
Adsorption Theory......Page 127
3.2.5 Breakdown of Passivity......Page 128
Pitting......Page 129
3.2.6 Corrosion Inhibitors......Page 130
3.2.6.1 Cathodic Inhibitors......Page 131
Self-Sufficient Oxidizing Inhibitors......Page 132
Safe and Dangerous Inhibitors......Page 133
3.3.1 Factors Promoting the Formation of Protective Oxides......Page 134
3.3.2 Thin Films and the Cabrera-Mott Theory......Page 135
3.3.3 Thick Films, Thermal Activation and the Wagner Theory......Page 136
Interface Equilibria......Page 137
Atomic Mechanisms......Page 138
Atomic Mechanisms......Page 139
3.3.3.4 Oxidation of Metals Forming Stoichiometric Ionic Oxides......Page 140
Electrical Conductivities of n-type and p-type oxides......Page 141
Valency Effects in Semi-conducting oxides......Page 142
3.3.3.8 Loss of Integrity of Protective Oxides......Page 143
3.3.4.1 Principles......Page 144
Example 10......Page 147
Solution:......Page 148
The Iron-Chromium-Oxygen System......Page 149
Further Reading......Page 151
Problems for Chapter 3......Page 152
Solution to Problem 1.......Page 154
Solution to Problem 3.......Page 155
Solution to Problem 4.......Page 156
Solution to Problem 5.......Page 157
Solution to Problem 6.......Page 158
Example 2.The Aluminum–Water System......Page 159
Example 3.The Zinc-Water System......Page 160
Example 4.The Copper-Water System......Page 163
Example 5.The Tin-Water System......Page 165
Example 6.The Nickel-Water System......Page 167
4.1 Galvanic Stimulation......Page 169
4.1.2 The Origin of the Bimetallic Effect......Page 170
4.1.3.1 Active and Weakly Passive Metals......Page 171
4.1.3.2 Active/Passive Couples......Page 172
4.1.3.4 Compatibility Groups......Page 173
4.1.3.5 Indirect Stimulation......Page 174
Example......Page 176
4.2.1 Principle......Page 177
Galvanic Protection of Steel by Coatings......Page 178
4.3 Cathodic Protection by Impressed Current......Page 179
Further Reading......Page 181
5.1.1 Characteristic Features......Page 182
5.1.2.1 Susceptible Alloys......Page 184
Grain Boundary Precipitation......Page 185
Hydrogen Embrittlement......Page 186
5.1.3.1 Brief Description of Phenomena......Page 187
5.1.3.4 Mechanisms......Page 188
5.1.4.1 Brief General Description of Phenomena......Page 189
5.2.1 Characteristic Features......Page 190
5.2.2.2 Intervention of the Environment......Page 192
5.3.2 Cavitation......Page 193
Stresses......Page 194
Further Reading......Page 195
6.1.1 Surface Conditions of Manufactured Metal Forms......Page 197
Surfaces of Press-Formed Products......Page 198
Weathering......Page 199
Acid Pickling......Page 200
Solvent Degreasing......Page 201
Alkaline Cleaning......Page 202
6.1.2.4 Chemical and Electrochemical Polishing of Aluminum Alloys......Page 203
6.2.1.1 Cathodic and Anodic Reactions......Page 205
6.2.1.2 Hydrogen Discharge......Page 206
6.2.1.3 Throwing Power......Page 207
6.2.2.1 General Considerations......Page 210
6.2.2.3 Other Nickel Plating Processes......Page 212
6.2.4.1 Applications......Page 213
6.2.4.3 Operation of Chromic Acid Baths......Page 214
6.2.4.4 Quality of the Deposit......Page 215
6.2.5.1 General Principles......Page 216
Acid Sulfate Baths......Page 217
6.2.5.3 Alkaline Stannate Baths......Page 218
Acid Sulfate Baths......Page 219
6.3.1 Zinc Coatings (Galvanizing)......Page 220
6.3.3 Aluminum Coatings......Page 221
6.4.1.1 Mechanism of Phosphating......Page 222
6.4.1.2 Accelerated Phosphating Processes......Page 223
6.4.2 Anodizing......Page 224
6.4.2.2 Practice......Page 225
Decorative Protective Coatings......Page 227
6.4.3 Chromating......Page 228
6.4.3.1 Coatings on Aluminum......Page 229
6.5 Paint Coatings For Metals......Page 231
6.5.1.1 Binding Media......Page 232
Blends for Air-Drying Paints......Page 233
6.5.1.2 Pigments and Extenders......Page 234
Water......Page 235
6.5.2.1 Traditional Paints......Page 236
6.5.3 Paint Formulation......Page 237
Further Reading......Page 238
7.1.1 Solid Solutions in Iron......Page 239
7.1.2 The Iron-Carbon System......Page 241
7.1.3.1 Normalized Steels......Page 242
7.1.3.2 Quenched and Tempered Steels......Page 243
7.1.4 Cast Irons......Page 244
7.2.1.1 Iron(III) Oxides, Hydrous Oxides, and Derivatives......Page 246
7.2.1.2 Iron(II) Oxides, Hydroxides, and Derivatives......Page 247
7.2.2.1 Fresh Waters......Page 248
7.2.2.3 Alkaline Waters......Page 250
7.2.3.1 Rusting Due to Atmospheric Humidity......Page 251
7.2.4 Rusting of Cast Irons......Page 253
7.2.4.2 Other Irons......Page 254
7.3.2 Phase Equilibria in the Iron-Oxygen System......Page 255
7.3.3.1 Nature of Scale......Page 257
7.3.3.2 Oxidation Rates......Page 258
7.3.4 Oxidation of Steels......Page 259
7.3.4.2 Influence on Metal Quality of Scales Formed During Manufacture......Page 260
7.3.5 Oxidation and Growth of Cast Irons......Page 261
Graphitization......Page 262
Further Reading......Page 263
8 - Stainless Steels......Page 264
8.1.1 The Iron-Chromium System......Page 265
8.1.2.2 Nickel......Page 266
8.1.2.3 Nickel and Carbon Present Together......Page 267
8.1.2.4 Molybdenum......Page 268
8.1.3 Schaeffler Diagrams......Page 269
Solution:......Page 270
8.2.2.1 Ferritic steels......Page 271
8.2.2.4 Duplex Steels......Page 273
8.3.1.2 Determination......Page 274
8.3.1.3 Presentation......Page 275
Acidic Media......Page 276
Neutral Halide media......Page 277
8.3.1.5 Influence of Steel Composition and Condition......Page 279
Non-oxidizing Acids......Page 281
Phosphoric Acid......Page 282
8.3.2.2 Pitting Corrosion......Page 283
Solution:......Page 285
8.3.2.4 Sensitization and Intergranular Corrosion......Page 286
8.4 Resistance to Dry Oxidation......Page 288
8.5.2.1 Austenitic Steels Without Molybdenum......Page 290
8.5.2.3 Austenitic Steels With Manganese Substitution......Page 291
8.5.5 Oxidation Resistant Steels......Page 292
Further Reading......Page 293
Solution to Problem 1.......Page 294
(d) Beer barrels......Page 295
Solution to Problem 3.......Page 296
9.1 Summary of Physical Metallurgy of Some Standard Alloys......Page 298
Commercial Pure Aluminum Grades (AA 1100 Alloy Series)......Page 299
The Aluminum-Manganese Alloy AA 3003......Page 301
9.1.2 Heat Treatable (Aging) Alloys......Page 302
Aluminum-Copper-Magnesium Alloys (e.g., AA 2024)......Page 303
Aluminum Alloys Containing Lithium......Page 304
9.2 Corrosion Resistance......Page 305
Trihydroxides......Page 306
9.2.1.2 Soluble Species......Page 307
9.2.2.1 Passivation......Page 308
Fresh Waters......Page 309
9.2.2.3 Corrosion Resistance in Acidic and Alkaline Media......Page 310
Magnesium......Page 311
Copper......Page 312
Intercrystalline and Exfoliation Corrosion......Page 313
9.2.3.3 Stress-Corrosion Cracking......Page 314
9.2.4.1 Nature of the Air-Formed Film......Page 315
9.2.5 Geometric Effects......Page 316
9.2.5.2 Impingement, Cavitation, and Erosion-Corrosion......Page 317
Further Reading......Page 318
10 - Corrosion and Corrosion Control in Aviation......Page 319
10.1.3 Corrosion of Aluminum Alloys in Airframes......Page 320
10.1.4.1 Corrosion of Aluminum Structures......Page 321
10.1.5 Systematic Assessment for Corrosion Control......Page 322
10.1.6.1 Fatigue......Page 323
10.2.1 Engine Operation......Page 324
10.2.2 Brief Review of Nickel Superalloys......Page 326
10.2.3.2 Aluminizing for Oxidation Resistance......Page 327
10.2.3.3 Hot Corrosion and Sulfidation......Page 328
10.2.4.1 Factors Related to Engine Operation......Page 329
10.2.4.2 Flight Pattern Factors......Page 330
10.2.5.1 Turbine Blades......Page 331
10.2.5.3 Combustion Chambers......Page 332
10.2.6 Monitoring and Technical Development......Page 334
Further Reading......Page 335
11.2.1 Design Considerations......Page 336
Wheel Arches......Page 337
11.2.2 Overview of Paint-Shop Operations......Page 338
11.2.4 Phosphating......Page 339
11.2.5.2 Undercoating Color and Gloss Coats......Page 342
11.3.1 Exhaust Systems......Page 343
11.3.2 Cooling Systems......Page 344
11.3.3 Moving Parts......Page 345
11.4.1 Electrodeposited Nickel Chromium Systems......Page 346
Further Reading......Page 347
12.1.1.1 Possible Toxic Effects......Page 348
12.1.1.2 Hygiene......Page 349
12.1.2.1 Bacteria in the Environment......Page 350
Degradation of Protective Mechanisms......Page 351
12.1.2.4 Corrosion Control in Practice......Page 352
12.2.2 Modern Tinplate Cans......Page 353
12.2.2.2 Two-Piece Draw/Redraw Cans (DRD)......Page 354
12.2.3.1 Steel Grades for Three-Piece Cans and Non-Critical Parts......Page 355
12.2.4 The Manufacture of Tinplate......Page 356
12.2.5 Tin-Free Steel for Packaging......Page 360
Hot-Rolling......Page 357
Cold-Rolling......Page 358
Continuous Annealing......Page 359
12.3.1.2 Constitution......Page 361
12.3.1.1 Processing......Page 362
Recovery of Proteins from Whey......Page 363
12.3.2.1 Surfaces in Contact with the Product......Page 364
12.4.1 The Brewing Process......Page 366
12.4.2.2 Stress-Corrosion Cracking......Page 368
12.4.2.4 Cleaning and Sterilization......Page 369
12.4.3.2 Design......Page 370
Aluminum Alloys......Page 371
Austenitic Stainless Steels......Page 372
Further Reading......Page 373
13.1 Introduction......Page 374
13.2.1.1 Reinforced Concrete......Page 375
Chloride Penetration......Page 376
13.2.1.3 Protective Measures Applied to the Concrete......Page 377
Epoxy Resin Coated Steel......Page 378
13.2.1.5 Stress-Corrosion Cracking of Pre-Stressed Reinforcement......Page 379
13.2.2.2 Protection......Page 380
13.2.3.2 Rainwater Goods......Page 381
13.3.2 Aluminum Alloy Panels......Page 382
13.4.1 Self-Supporting Roofs and Siding......Page 383
13.4.2 Fully Supported Roofs and Flashings......Page 384
Copper......Page 385
13.5.4 Central-Heating Circuits......Page 386
13.6.1 Contact Corrosion......Page 387
13.6.2 Corrosion by Vapors from Wood......Page 388
Safety-Critical Damage by Stress-Corrosion Cracking......Page 389
13.7.2 Control......Page 390
Further Reading......Page 391