Effect of cyclic plastic strain and flow stress on low cycle fatigue life of 316L(N) stainless steel

Hysteresis loop can lead to cyclic plastic deformation. Both cyclic style and amplitude of cyclic plastic strain in a saturated cycle are very different from that of applied strain. Cyclic plastic strain and its corresponding stress (flow stress) are strongly dependent on hysteresis loop. Considering that fatigue damage accumulation is mainly induced by cyclic plastic deformation, a damage model for low cycle fatigue has been proposed based on flow stress. The whole ɛ−N curve, not only the linear part, but also the curve part, can be well described by this model. Examinations with experimental results of 316L(N) stainless steel show that it can also be used to the case even the ɛ−N curve is not smooth.