ApL787
| ApL787 | |
|---|---|
| Fatigue Failure and Design | |
| Credits | 3 |
| Structure | 3-0-0 |
| Pre-requisites | APL 104/APL 105/APL 108 and 75 credits for |
| Overlaps | |
ApL787 : Fatigue Failure and Design
[edit]UG students Course Contents: Historical overview; Fatigue design philosophies; Stress-life approach: SN diagram, mean stress effects, notches; Strain-life approach: hysteresis loop, Bauschinger effect, shakedown, ratcheting, energy methods, Neuber's rule; Damage-tolerance approach: introduction to fracture, crack tip plasticity, fracture toughness, crack growth stages, crack closure, small fatigue cracks; Physics of fatigue: imperfections in crystalline solids, slip bands, intrusions/extrusions, crack initiation, microstructure effects; Residual stresses: origin, measurement methods, relationship with fatigue; Fatigue under variable amplitude loading: load spectrums, linear and nonlinear cumulative damage models, load interaction and sequence effects, rainflow method, life estimation; Multiaxial fatigue: multiaxial stress state, proportional and nonproportional loading, yielding and plasticity in multiaxial fatigue, stress-based criteria (Sines method), strain- and energy-based approaches, critical plane approach (Fatemi-Socie model); Environmental effects: corrosion, fretting, thermomechanical damage ( creep and creep-fatigue interactions), neutron irradiation; Statistical aspects of fatigue: regression analysis of fatigue data, fatigue scatter lognormal and Weibull distributions, tolerance limits, reliability analysis.