Introduction of the normalized damage function for the creep-fatigue life prediction of austenitic stainless steels

摘要

For the austenitic stainless steels, it is well known that grain boundary cracking due to the cavitation is one of the most detrimental degradation processes for the reduction of the creep-fatigue life at high temperatures.A new unified damage function based on a model of the grain boundary cavity formation by fatigue and growth by the creep effect for the creep-fatigue life prediction is introduced.This unique normalized damage function includes the cavity nucleation process by fatigue and cavity growth process by creep deformation under various combinations of temperature, stress, plastic strain range, strain rate and hold time.