1 Stress and Strain 1
Introduction 1
Stress 2
Sign Convention 3
Transformation of Axes 4
Principal Stresses 6
Mohr’s Stress Circles 6
Strains 9
Small Strains 11
Transformation of Axes 12
Mohr’s Strain Circles 14
Force and Moment Balances 15
Boundary Conditions 16
Note 17
Problems 18
2 Elasticity 21
Introduction 21
Isotropic Elasticity 21
Variation of Young’s Modulus 24
Isotropic Thermal Expansion 26
Anisotropic Elasticity 27
Orientation Dependence of Elastic Response 29
Orientation Dependence in Cubic Crystals 31
Orientation Dependence in Noncubic Crystals 32
Orientation Dependence in Materials Other Than Single Crystals 34
Anisotropic Thermal Expansion 34
Notes 35
References 36
Problems 36
3 Tensile Testing 39
Introduction 39
Tensile Specimens 39
Stress-Strain Curves 40
Ductility 43
True Stress and Strain 44
The Bridgman Correction 45
Temperature Rise 47
Sheet Anisotropy 47
Measurement of Force and Strain 48
Axial Alignment 49
Special Problems 49
Notes 50
References 51
Problems 51
4 Other Tests of Plastic Behavior 53
Introduction 53
Compression Test 53
Plane-Strain Compression 56
Plane-Strain Tension 57
Biaxial Tension （Hydraulic Bulge Test） 57
Torsion Test 59
Bend Tests 61
Hardness Tests 62
Mutual Indentation Hardness 66
Note 67
References 67
Problems 67
5 Strain-Hardening of Metals 70
Introduction 70
Mathematical Approximations 70
Power-Law Approximation 72
Necking 73
Work per Volume 75
Localization of Strain at Defects 75
Notes 76
Problems 77
6 Plasticity Theory 80
Introduction 80
Yield Criteria 80
Tresca Maximum Shear Stress Criterion 81
Von Mises Criterion 82
Flow Rules 84
Principle of Normality 85
Effective Stress and Effective Strain 86
Other Isotropic Yield Criteria 89
Anisotropic Plasticity 90
Effect of Strain-Hardening on the Yield Locus 93
Notes 93
References 94
Problems 94
7 Strain-Rate and Temperature Dependence of Flow Stress 99
Introduction 99
Strain-Rate Dependence of Flow Stress 99
Superplasticity 102
Combined Strain and Strain-Rate Effects 106
Strain-Rate Sensitivity of bcc Metals 107
Temperature Dependence 110
Combined Temperature and Strain-Rate Effects 111
Hot Working 115
Notes 116
References 116
Problems 116
8 Slip 120
Introduction 120
Slip Systems 120
Schmid’s Law 121
Strains Produced by Slip 123
Strain-Hardening of fcc Single Crystals 125
Tensile Deformation of fcc Crystals 126
Slip in bcc Crystals 128
Slip in hcp Crystals 128
Lattice Rotation in Tension 129
Lattice Rotation in Compression 131
Texture Formation in Polycrystals 132
Approximate Calculation of R-Values 133
Notes 134
References 135
Problems 135
9 Dislocation Geometry and Energy 139
Introduction 139
Theoretical Strength of Crystals 139
The Nature of Dislocations 141
Burgers Vectors 142
Energy of a Screw Dislocation 144
Reactions between Parallel Dislocations and Frank’s Rule 146
Stress Fields around Dislocations 147
Forces on Dislocations 149
Partial Dislocations in fcc Crystals 150
Stacking Faults 151
Notes 154
References 154
Problems 156
10 Dislocation Mechanics 158
Introduction 158
Frank-Read Sources 158
Dislocation Pile-Ups 161
Cross-Slip 161
Dislocation Intersections 163
Climb 166
Notes 166
References 167
Problems 167
11 Mechanical Twinning and Martensitic Shear 170
Introduction 171
Formal Notation 171
Twinning Shear 172
Twinning in fcc Metals 173
Twinning in bcc Metals 173
Twinning in hcp Metals 175
Shapes of Twins 178
Mechanism of Twinning 179
Martensite Transformation 182
Shape Memory and Superelasticity 183
Notes 184
References 185
Problems 186
12 Hardening Mechanisms in Metals 188
Introduction 188
Deformation of Polycrystals 188
Texture Strengthening 190
Crystal Structure 191
Grain Size 193
Strain-Hardening 194
Solid-Solution Strengthening 195
Dispersion Strengthening 196
Yield Points and Strain-Aging 199
Dynamic Strain-Aging 201
Combined Effects 202
Notes 206
References 206
Problems 206
13 Ductility and Fracture 210
Introduction 210
Ductile Fracture 212
Brittle Fracture 217
Impact Energy 220
Notes 224
References 224
Problems 225
14 Fracture Mechanics 227
Introduction 227
Theoretical Fracture Strength 227
Stress Concentration 229
Griffith Theory 230
Orowan Theory 231
Fracture Modes 231
Irwin’s Fracture Analysis 231
Plastic Zone Size 233
Thin Sheets 235
Temperature and Loading Rate 236
Metallurgical Variables 237
Fracture Mechanics in Design 237
Compact Tensile Specimens 239
Strain-Energy Release 240
The J-integral 241
Notes 242
References 243
Problems 243
Appendix Ⅰ 245
Size and Shape of the Plastic Zone at a Crack Tip 245
1 5 Viscoelasticity 247
Introduction 247
Rheological Models 247
Series Combination of a Spring and Dashpot 248
Parallel Combination of a Spring and Dashpot 249
Combined Parallel-Series Model 250
More Complex Models 251
Damping 251
Natural Decay 253
Elastic Modulus - Relaxed Versus Unrelaxed 254
Thermoelastic Effect 255
Snoek Effect in bcc Metals 256
Other Damping Mechanisms 257
References 258
Notes 258
Problems 259
16 Creep and Stress Rupture 262
Introduction 262
Creep Mechanisms 262
Temperature Dependence of Creep 266
Deformation Mechanism Maps 267
Cavitation 268
Rupture Versus Creep 269
Extrapolation Schemes 270
Alloys for High-Temperature Use 273
Notes 275
References 275
Problems 276
17 Fatigue 279
Introduction 279
Surface Observations 279
Nomenclature 281
S-N Curves 282
Effect of Mean Stress 283
The Palmgren-Miner Rule 285
Stress Concentration 286
Surfaces 288
Design Estimates 290
Metallurgical Variables 291
Strains to Failure 291
Crack Propagation 294
Cyclic Stress-Strain Behavior 296
Temperature and Cycling Rate Effects 297
Fatigue of Polymers 300
Fatigue Testing 302
Design Considerations 302
Summary 303
Notes 303
References 304
Problems 304
18 Residual Stresses 308
Introduction 308
Small-Scale Stresses 308
Bauschinger Effect 311
Nonuniform Cooling 312
Nonuniform Material 313
Stresses from Welding 313
Stresses from Mechanical Working 314
Consequences of Residual Stresses 316
Measurement of Residual Stresses 317
Relief of Residual Stresses 319
Notes 321
References 321
Problems 321
19 Ceramics and Glasses 324
Introduction 324
Elastic Properties 324
Slip Systems 325
Hardness 326
Weibull Analysis 326
Testing 329
Porosity 329
High-Temperature Behavior 331
Fracture Toughness 331
Toughening of Ceramics 334
Fatigue 335
Silicate Glasses 335
Strength of Glasses 338
Thermally Induced Stresses 339
Delayed Fracture 340
Glassy Metals 341
Notes 342
References 343
Problems 343
20 Polymers 345
Introduction 345
Elastic Behavior 345
Rubber Elasticity 350
Damping 353
Yielding 353
Effect of Strain Rate 356
Effect of Pressure 356
Crazing 361
Yielding of Fibers in Compression 363
Fracture 364
Deformation Mechanism Maps 366
Shape-Memory Effect 367
References 368
Notes 368
Problems 370
21 Composites 372
Introduction 372
Fiber-Reinforced Composites 372
Elastic Properties of Fiber-Reinforced Composites 372
Strength of Fiber-Reinforced Composites 376
Volume Fraction of Fibers 377
Orientation Dependence of Strength 378
Fiber Length 379
Failures with Discontinuous Fibers 381
Failure under Compression 382
Typical Properties 383
Particulate Composites 384
Brick-Wall Model 385
Lamellar Composites 387
Notes 388
References 389
Problems 389
22 Mechanical Working 392
Introduction 392
Bulk-Forming Energy Balance 392
Deformation Zone Geometry 396
Friction in Bulk Forming 399
Formability 400
Deep Drawing 401
Stamping 403
Notes 407
References 409
Problems 409
Appendix A 413
Appendix B 418
Index 421