High Cycle Fatigue: A Mechanics of Materials Perspective

Cover......Page 1
Contents......Page 6
Preface......Page 11
Introduction and Background......Page 16
Historical background......Page 18
What is High Cycle Fatigue?......Page 19
HCF design considerations......Page 20
HCF design requirements......Page 24
Root causes of HCF......Page 26
Field failures......Page 28
Damage tolerance......Page 31
Application to HCF......Page 35
Current status......Page 38
Field experience......Page 40
Gigacycle fatigue......Page 42
Characterizing fatigue cycles......Page 49
Fatigue limit stresses......Page 50
Equations for constant life diagrams......Page 56
Haigh diagram at elevated temperature......Page 62
Role of mean stress in constant life diagrams......Page 66
Jasper equation......Page 71
Observations on step tests at negative R......Page 80
Coaxing......Page 85
Early test methods......Page 87
Step test procedures......Page 90
Statistical considerations......Page 91
Influence of number of steps......Page 93
Validation of the step-test procedure......Page 95
Observations from the last loading block......Page 100
Comments on step testing......Page 104
Staircase testing......Page 105
Probability plots......Page 106
Dixon and Mood method......Page 110
Numerical simulations......Page 114
Sample size considerations......Page 119
Construction of an “artificial” staircase......Page 120
Other methods......Page 121
Random fatigue limit (RFL) model......Page 124
Data analysis......Page 128
Summary comments on FLS statistics......Page 135
Constant stress tests......Page 138
Run-outs and maximum likelihood (ML) methods......Page 141
Resonance testing techniques......Page 144
Frequency effects......Page 149
Effects of Damage on HCF Properties......Page 158
Small cracks and the Kitagawa diagram......Page 160
Behavior of notched specimens......Page 164
Effects of LCF loading on HCF limit stress......Page 168
Crack-propagation thresholds......Page 185
Overloads and load-history effects......Page 187
An overload model......Page 195
Analysis using an overload model......Page 197
Examples of LCF–HCF interactions......Page 198
Design considerations......Page 208
LCF–HCF nomenclature......Page 211
Example of anomalous behavior......Page 212
Another example of anomalous behavior......Page 215
Combined cycle fatigue case studies......Page 219
Stress concentration factor......Page 228
What is kt?......Page 230
Fatigue notch factor......Page 231
kf versus kt relations......Page 232
Equations for kf......Page 233
Fracture mechanics approaches for sharp notches......Page 237
Cracks versus notches......Page 240
Mean stress considerations......Page 243
Plasticity considerations......Page 247
Negative mean stresses......Page 253
Fatigue limit strength of notched components......Page 254
Non-damaging notches......Page 256
Critical distance approaches......Page 257
Analysis methods......Page 261
Effects of defects on fatigue strength......Page 266
Notch fatigue at elevated temperature......Page 269
Introduction......Page 276
Observations of fretting fatigue......Page 278
Representing total contact loads, Q and P......Page 282
Load and stress distributions......Page 286
Effects of local and bulk stresses on stress intensity......Page 287
Mechanisms of fretting fatigue......Page 292
Mechanics of fretting fatigue......Page 294
Stress analysis of contact regions......Page 296
Multiple crack considerations......Page 298
Analytical solutions......Page 299
Role of slip amplitude......Page 307
Stress-at-a-point approaches......Page 310
Fracture mechanics approaches......Page 315
A combined stress and K approach......Page 321
Comparison of fretting-fatigue fixtures......Page 324
Role of coefficient of friction......Page 327
Summary comments......Page 332
Introduction......Page 337
Field experience and observations......Page 339
Repair by blending......Page 340
FOD data mining and investigation......Page 341
Definition of FOD......Page 343
Types of damage......Page 344
Scope of the FOD problem......Page 351
Pendulum......Page 353
Simulations using a leading edge geometry......Page 354
Role of residual stresses......Page 359
Energy considerations......Page 360
Fatigue limit strength......Page 362
Simulations using a flat plate......Page 367
Other laboratory FOD simulations......Page 374
Analytical modeling of FOD......Page 382
Perturbation study......Page 386
Summary comments......Page 389
Applications......Page 392
Factors of safety......Page 394
Modeling errors......Page 396
Material variability......Page 399
Fracture mechanics considerations......Page 401
Effects of defects......Page 405
Application to LCF–HCF......Page 411
Damage tolerance for HCF......Page 413
Material allowables......Page 415
Threshold concept for HCF......Page 418
Representing fatigue limit data......Page 420
Threshold considerations......Page 423
“Jump-in” method......Page 424
Mechanisms in threshold testing......Page 427
Load-history effects......Page 429
Load-shed rates......Page 431
Crack closure......Page 433
Kmax−DeltaK concept......Page 434
Crack propagation stress intensity factor......Page 437
An engineering approach to thresholds......Page 438
Observations from field failures......Page 439
Probabilistic approach to HCF/FOD design......Page 440
Residual stresses in HCF design......Page 445
Application to notches......Page 451
Shot peening......Page 456
Deep residual stresses......Page 462
Application to an airfoil geometry......Page 464
Crack arrest......Page 473
Crack growth retardation......Page 476
A numerical example......Page 477
Autofrettage......Page 479
Early Railroad Accidents and the Origins of Research on Fatigue of Metals......Page 487
Final Report for the USAF High Cycle Fatigue Program......Page 508
HCF in ENSIP......Page 514
Evaluation of the Staircase Test Method using Numerical Simulation......Page 532
Estimation of HCF Threshold Stress Levels in Notched Components......Page 546
Analytical Modeling of Contact Stresses......Page 557
Experimental and Analytical Simulation of FOD......Page 573
FOD in JSSG......Page 615
Computation of High Cycle Fatigue Design Limits under Combined High and Low Cycle Fatigue......Page 632
Index......Page 654