Mechanical Properties of Engineered Materials

Cover\r......Page 1
Title\r......Page 2
Preface......Page 4
Table of Contents......Page 7
1.2 ATOMIC STRUCTURE......Page 14
1.3.1.1 Ionic Bonding......Page 15
1.3.1.2 Covalent Bonds......Page 17
1.3.1.3 Metallic Bonds......Page 19
1.3.2.1 Temporary Dipoles......Page 20
1.4.1 Polymers......Page 21
1.4.2 Metals and Ceramics......Page 24
1.4.4 Semiconductors......Page 28
1.4.5 Composites......Page 29
1.5 STRUCTURAL LENGTH SCALES: NANOSTRUCTURE, MICROSTRUCTURE, AND MACROSTRUCTURE......Page 32
1.6 SUMMARY......Page 33
BIBLIOGRAPHY......Page 34
2.2 INDICIAL NOTATION FOR ATOMIC PLANES AND DIRECTIONS......Page 36
2.2.1 Miller Indicial Notation......Page 37
2.2.2 Miller–Bravais Indicial Notation......Page 39
2.3 DEFECTS......Page 41
2.3.2 Line Defects......Page 42
2.3.3 Surface Defects......Page 44
2.3.4 Volume Defects......Page 45
2.4.1 Statistical Mechanics Background......Page 46
2.4.2 Diffusion......Page 47
2.4.3 Phase Nucleation and Growth......Page 48
2.4.4 Introduction to Phase Diagrams......Page 52
2.4.5.1 Time–Temperature–Transformation Diagrams......Page 57
2.4.5.2 Continuous Cooling–Transformation Diagrams......Page 62
2.5.1 Tensile and Compressive Properties......Page 64
2.5.3 Strength......Page 65
2.5.4 Hardness......Page 66
2.5.5 Fracture......Page 67
2.5.6 Creep......Page 68
2.5.8 Environmental Effects......Page 69
BIBLIOGRAPHY......Page 70
3.2 BASIC DEFINITIONS OF STRESS......Page 72
3.3 BASIC DEFINITIONS OF STRAIN......Page 77
3.4 MOHR’S CIRCLE OF STRESS AND STRAIN......Page 83
3.5 COMPUTATION OF PRINCIPAL STRESSES AND PRINCIPAL STRAINS......Page 85
3.6 HYDROSTATIC AND DEVIATORIC STRESS COMPONENTS......Page 88
3.7.1 Strain Gauge Measurements......Page 91
3.7.2. Introduction to Photoelasticity......Page 93
3.8 MECHANICAL TESTING......Page 94
BIBLIOGRAPHY......Page 97
4.1 INTRODUCTION......Page 98
4.2 REASONS FOR ELASTIC BEHAVIOR......Page 99
4.3 INTRODUCTION TO LINEAR ELASTICITY......Page 102
4.4.1 Introduction......Page 106
4.4.2 Equilibrium Equations......Page 109
4.4.3.1 Plane Stress and Plane Strain Conditions......Page 111
4.4.3.2 Generalized Three-Dimensional State of Stress......Page 113
4.4.3.3 Compatibility Conditions and Stress Functions......Page 114
4.5 INTRODUCTION TO TENSOR NOTATION......Page 116
4.6 GENERALIZED FORM OF LINEAR ELASTICITY......Page 120
4.7 STRAIN ENERGY DENSITY FUNCTION......Page 122
4.8 SUMMARY......Page 123
BIBLIOGRAPHY......Page 124
5.1 INTRODUCTION......Page 125
5.2.1 Plasticity in Ceramics......Page 126
5.2.2 Plasticity in Metals......Page 128
5.2.3 Plasticity in Intermetallics......Page 132
5.2.4 Plasticity in Polymers......Page 133
5.3 ELASTIC–PLASTIC BEHAVIOR......Page 134
5.4 EMPIRICAL STRESS–STRAIN RELATIONSHIPS......Page 141
5.5 CONSIDERE CRITERION......Page 144
5.6.1 Introduction......Page 146
5.6.2.2 Von Mises Yield Criterion......Page 147
5.7 INTRODUCTION TO J2 DEFORMATION THEORY......Page 149
5.8 FLOW AND EVOLUTIONARY EQUATIONS (CONSTITUTIVE EQUATIONS OF PLASTICITY)......Page 151
BIBLIOGRAPHY......Page 152
6.1 INTRODUCTION......Page 154
6.2 THEORETICAL SHEAR STRENGTH OF A CRYSTALLINE SOLID......Page 155
6.3.1 Edge Dislocations......Page 157
6.3.3 Mixed Dislocations......Page 159
6.4 MOVEMENT OF DISLOCATIONS......Page 161
6.4.1 Movement of Edge Dislocations......Page 165
6.4.2 Movement of Screw Dislocations......Page 166
6.4.3 Movement of Mixed Dislocations......Page 167
6.5 EXPERIMENTAL OBSERVATIONS OF DISLOCATIONS......Page 169
6.6 STRESS FIELDS AROUND DISLOCATIONS......Page 170
6.6.1 Stress Field Around a Screw Dislocation......Page 172
6.6.2 Stress and Strain Fields Around an Edge Dislocation......Page 174
6.7 STRAIN ENERGIES......Page 176
6.8 FORCES ON DISLOCATIONS......Page 178
6.9 FORCES BETWEEN DISLOCATIONS......Page 182
6.10 FORCES BETWEEN DISLOCATIONS AND FREE SURFACES......Page 186
BIBLIOGRAPHY......Page 188
7.1 INTRODUCTION......Page 190
7.2 DISLOCATION MOTION IN CRYSTALS......Page 191
7.3 DISLOCATION VELOCITY......Page 194
7.4 DISLOCATION INTERACTIONS......Page 196
7.5 DISLOCATION BOWING DUE TO LINE TENSION......Page 200
7.6 DISLOCATION MULTIPLICATION......Page 201
7.7 CONTRIBUTIONS FROM DISLOCATION DENSITY TO MACROSCOPIC STRAIN......Page 204
7.8.2 Slip in Body-Centered Cubic Structures......Page 206
7.8.4 Condition for Homogeneous Plastic Deformation......Page 208
7.8.5 Partial or Extended Dislocations......Page 210
7.8.6 Superdislocations......Page 214
7.9 CRITICAL RESOLVED SHEAR STRESS AND SLIP IN SINGLE CRYSTALS......Page 215
7.10 SLIP IN POLYCRYSTALS......Page 219
7.11 GEOMETRICALLY NECESSARY AND STATISTICALLY STORED DISLOCATIONS......Page 222
7.12 DISLOCATION PILE-UPS AND BAUSCHINGER EFFECT......Page 229
7.13 MECHANICAL INSTABILITIES AND ANOMALOUS/SERRATED YIELDING......Page 231
7.13.1 Anomalous Yielding Phenomena......Page 232
7.13.2 Portevin–LeChatelier Effect......Page 233
BIBLIOGRAPHY......Page 234
8.1 INTRODUCTION......Page 237
8.2 DISLOCATION INTERACTIONS WITH OBSTACLES......Page 238
8.3 SOLID SOLUTION STRENGTHENING......Page 239
8.4 DISLOCATION STRENGTHENING......Page 242
8.5 GRAIN BOUNDARY STRENGTHENING......Page 244
8.6 PRECIPITATION STRENGTHENING......Page 247
8.6.1 Dislocation/Orowan Strengthening......Page 248
8.6.2 Strengthening by Dislocation Shearing or Cutting of Precipitates......Page 250
8.6.3 Dislocation Looping Versus Shear......Page 253
8.6.4. Precipitation Strengthening of Aluminum Alloys......Page 254
8.7 DISPERSION STRENGTHENING......Page 257
8.8 OVERALL SUPERPOSITION......Page 258
BIBLIOGRAPHY......Page 259
9.1 INTRODUCTION......Page 261
9.2 TYPES OF COMPOSITE MATERIALS......Page 262
9.3.1 Constant-Strain and Constant-Stress Rules of Mixtures......Page 270
9.4 DEFORMATION BEHAVIOR OF UNIDIRECTIONAL COMPOSITES......Page 275
9.5 MATRIX VERSUS COMPOSITE FAILURE MODES IN UNIDIRECTIONAL COMPOSITES......Page 278
9.6 FAILURE OF OFF-AXIS COMPOSITES......Page 280
9.7 EFFECTS OF WHISKER/FIBER LENGTH ON COMPOSITE STRENGTH AND MODULUS......Page 284
9.8.1 Fibers and Matrix Materials......Page 288
9.8.2.1 Polymer Composites......Page 290
9.8.2.2 Ceramic Matrix Composites......Page 291
9.8.2.3 Metal Matrix Composites......Page 293
9.9 STATISTICAL VARIATIONS IN COMPOSITE STRENGTH......Page 295
BIBLIOGRAPHY......Page 300
10.1 INTRODUCTION......Page 302
10.2 UNIDIRECTIONAL LAMINATES......Page 303
10.3 OFF-AXIS LAMINATES......Page 305
10.4 MULTIPLY LAMINATES......Page 308
10.5 COMPOSITE PLY DESIGN......Page 313
10.6.1 Critical Stress or Critical Strain Approaches......Page 315
10.6.2 Interactive Failure Criteria......Page 316
10.7 SHEAR LAG THEORY......Page 317
10.8 THE ROLE OF INTERFACES......Page 321
BIBLIOGRAPHY......Page 326
11.1 INTRODUCTION......Page 328
11.3 NOTCH CONCENTRATION FACTORS......Page 330
11.4 GRIFFITH FRACTURE ANALYSIS......Page 331
11.5.1 Load Control or Deadweight Loading......Page 333
11.5.2 Displacement-Controlled Loading......Page 335
11.5.3 In.uence of Machine Compliance......Page 336
11.6.1 Derivation of Crack-Tip Fields......Page 337
11.6.2 Crack Driving Force and Concept of Similitude......Page 345
11.6.3.1 Plastic Zone Size for Plane Stress and Plane Strain Conditions......Page 348
11.6.3.2 Dugdale Model......Page 349
11.6.5 Equivalence of G and K......Page 351
11.6.5.1 Worked Example—G and K for Double Cantilever Bend Specimen......Page 353
11.7.1 Crack Opening Displacement......Page 355
11.7.2 The J Integral......Page 356
11.7.3 Conditions of J Dominance......Page 360
11.7.4 Two-Parameter J–Q......Page 363
11.8 FRACTURE INITIATION AND RESISTANCE......Page 364
11.9 INTERFACIAL FRACTURE MECHANICS......Page 368
11.10 DYNAMIC FRACTURE MECHANICS......Page 372
BIBLIOGRAPHY......Page 374
12.1 INTRODUCTION......Page 379
12.2 FRACTOGRAPHIC ANALYSIS......Page 380
12.3 TOUGHNESS AND FRACTURE PROCESS ZONES......Page 382
12.4.2 Cleavage Fracture......Page 384
12.4.3 Ductile Fracture......Page 393
12.4.4 Intergranular Fracture......Page 397
12.5 FRACTURE OF INTERMETALLICS......Page 398
12.6 FRACTURE OF CERAMICS......Page 400
12.7 FRACTURE OF POLYMERS......Page 402
12.8 FRACTURE OF COMPOSITES......Page 406
12.9 QUANTITATIVE FRACTOGRAPHY......Page 409
12.10.1 Review of Thermal Shock......Page 410
12.10.2 Materials Selection for Thermal Shock Resistance......Page 417
12.11 SUMMARY......Page 423
BIBLIOGRAPHY......Page 424
13.1 INTRODUCTION......Page 427
13.1.1 Historical Perspective......Page 428
13.2 TOUGHENING AND TENSILE STRENGTH......Page 429
13.3 REVIEW OF COMPOSITE MATERIALS......Page 431
13.4 TRANSFORMATION TOUGHENING......Page 432
13.5 CRACK BRIDGING......Page 439
13.5.1 Bridging By Ductile Phase......Page 440
13.5.2 Crack Bridging by Discontinuous Reinforcements......Page 444
13.5.3 Bridging by Stiff Fibers and Fiber Pull-Out......Page 446
13.6 CRACK-TIP BLUNTING......Page 449
13.7 CRACK DEFLECTION......Page 453
13.8 TWIN TOUGHENING......Page 455
13.9 CRACK TRAPPING......Page 456
13.11 LINEAR SUPERPOSITION CONCEPT......Page 458
13.12 SYNERGISTIC TOUGHENING CONCEPT......Page 459
13.13 TOUGHENING OF POLYMERS......Page 462
13.14 SUMMARY AND CONCLUDING REMARKS......Page 464
BIBLIOGRAPHY......Page 465
14.1 INTRODUCTION......Page 469
14.2 MICROMECHANISMS OF FATIGUE CRACK INITIATION......Page 473
14.3 MICROMECHANISMS OF FATIGUE CRACK PROPAGATION......Page 475
14.4.1 Stress Amplitude or Stress Range Approach......Page 480
14.4.2 Strain-range Approach......Page 482
14.4.3 Effects of Mean Stress......Page 484
14.4.4 Fatigue Behavior in Smooth Specimens......Page 485
14.5 DIFFERENTIAL APPROACH TO FATIGUE......Page 486
14.6 FATIGUE CRACK GROWTH IN DUCTILE SOLIDS......Page 487
14.7 FATIGUE OF POLYMERS......Page 490
14.8.2 Growth of Cracks......Page 493
14.9.1 Introduction......Page 499
14.9.4 Oxide-induced Closure......Page 502
14.9.6 Closure Measurement Techniques......Page 504
14.10 SHORT CRACK PROBLEM......Page 506
14.11 FATIGUE GROWTH LAWS AND FATIGUE LIFE PREDICTION......Page 509
14.12 FATIGUE OF COMPOSITES......Page 512
14.13 SUMMARY......Page 517
BIBLIOGRAPHY......Page 518
15.1 INTRODUCTION......Page 524
15.2.2 Maxwell and Voigt Models......Page 526
15.2.2.1 Maxwell Model......Page 527
15.2.2.2 Voigt Model......Page 529
15.3 MECHANICAL DAMPING......Page 533
15.4 TEMPERATURE DEPENDENCE OF TIMEDEPENDENT FLOW IN POLYMERS......Page 536
15.5 INTRODUCTION TO CREEP IN METALLIC AND CERAMIC MATERIALS......Page 538
15.6 FUNCTIONAL FORMS IN THE DIFFERENT CREEP REGIMES......Page 541
15.7 SECONDARY CREEP DEFORMATION AND DIFFUSION......Page 544
15.8.1 Introduction......Page 546
15.8.2 Dislocation Creep......Page 549
15.8.3 Diffusion Creep and Grain Boundary Sliding......Page 550
15.8.4 Deformation Mechanism Maps......Page 552
15.9 CREEP LIFE PREDICTION......Page 555
15.10 CREEP DESIGN APPROACHES......Page 557
15.11 THRESHOLD STRESS EFFECTS......Page 559
15.12 CREEP IN COMPOSITE MATERIALS......Page 560
15.13 THERMOSTRUCTURAL MATERIALS......Page 561
15.14 INTRODUCTION TO SUPERPLASTICITY......Page 569
15.15.1 Creep Damage......Page 575
15.15.2 Time-Dependent Fracture Mechanics......Page 577
15.16 SUMMARY......Page 580
BIBLIOGRAPHY......Page 581