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Slip and Crystallographic Textures . . . . . . . . . . . . . . . . . . . . . . . . . . 113
Introduction 113
Slip Systems 113
Schmid’s Law 113
Strains Produced by Slip 116
Strain Hardening of fcc Single Crystals 117
Tensile Deformation of fcc Crystals 118
Slip in bcc Crystals 120
Slip in hcp Crystals 121
Lattice Rotation in Tension 121
Lattice Rotation in Compression 123
Texture Formation in Polycrystals 124
Approximate Calculations of R Values 125
Deformation of Polycrystals 126
Texture Strengthening 127
Effects of Texture on Microstructure 128
References 132
Notes 132
Problems 133
8 Dislocation Geometry and Energy . . . . . . . . . . . . . . . . . . . . . . . . . . 137
Introduction 137
Theoretical Strength of Crystals 137
The Nature of Dislocations 139
Burgers Vectors 141
Energy of a Screw Dislocation 142
Reactions between Parallel Dislocations and Frank’s Rule 144
Stress Fields around Dislocations 144
Forces on Dislocations 146
Partial Dislocations in fcc Crystals 147
Stacking Faults 149
viii Contents
References 152
Notes 152
Problems 153
9 Dislocation Mechanics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155
Introduction 155
Frank-Read Sources 155
Dislocation Pile-Ups 158
Cross-Slip 158
Dislocation Intersections 159
Climb 163
References 163
Note 163
Problems 164
10 Mechanical Twinning and Martenitic Shear . . . . . . . . . . . . . . . . . . . 166
Introduction 166
Formal Notation 167
Twinning Shear 167
Twinning in fcc Metals 169
Twinning in bcc Metals 169
Twinning in hcp Metals 171
Shapes of Twins 173
Mechanism of Twinning 175
Martensite Transformation 178
Shape Memory and Superelasticity 178
References 181
Note 181
Problems 181
11 Hardening Mechanisms in Metals . . . . . . . . . . . . . . . . . . . . . . . . . . 184
Introduction 184
Crystal Structure 184
Grain Size 184
Strain Hardening 186
Solid Solution Strengthening 187
Dispersion Strengthening 188
Yield Points and Strain Aging 191
Combined Effects 192
References 195
Notes 195
Problems 196
12 Discontinuous and Inhomogeneous Deformation . . . . . . . . . . . . . . . 199
Stick-Slip Phenomena 199
Dynamic Strain Aging 200
Other Causes of Serrated Stress–Strain Curves 205
Contents ix
Strain Localization 205
Reference 206
Notes 206
Problems 206
13 Ductility and Fracture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 208
Introduction 208
Ductile Fracture 210
Brittle Fracture 216
Impact Energy 218
References 221
Notes 221
Problems
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