Low-Cycle Fatigue of Metals-Literature Review

Abstract

Evaluation of data on low-cycle fatigue of metals based on type of test, cyclic rate, stress concentration, crack propagation, material property change and method of analysis indicates that (a) there is presently no general analysis applicable to all low-cycle fatigue test conditions; (b) the shape of the load-time curve is important in analyzing low-cycle fatigue test; (c) the extent of the time effect on low-cycle fatigue behavior, particularly with respect to creep and crack propagation, remains to be explored; (d) use of strain rather than stress is more desirable in low-cycle fatigue studies of coupon-type specimens because of the plastic deformation that takes place during such tests; and (e) the fatigue hypotheses based on strain, although developed from limited data, exhibit good agreement with the test results and show promise of providing a good indication of low-cycle fatigue behavior for selected loading condi ions. (Author)