An efficient fatigue and creep-fatigue life prediction method by using the hysteresis energy density rate concept

Fatigue damage, time-dependent creep damage and their interaction are considered as the main failure mechanisms for many high temperature structural components. A generalized methodology for predicting both the high temperature low cycle fatigue (HTLCF) and creep-fatigue lives by using the hysteresis energy density rate (HEDR) and fatigue damage stress concepts was proposed. Experimental data for HTLCF and creep-fatigue in Alloy 617, Haynes 230 and P92 steel were respectively collected to validate the method. A better prediction capacity and most of the data points that fall within a 1.5 scatter band were obtained compared with the traditional energy-based method, time fraction rule and ductility exhaustion model. Moreover, a creep-fatigue damage diagram was also constructed by using the proposed approach.