Evaluation of the low-cycle fatigue behaviors of stainless-steel elbows having local wall thinning

Abstract

Elbow pipes present a complex stress state, and it is difficult to predict their failure behavior. In previous studies, low-cycle fatigue tests were performed on carbon steel elbow pipes and the revised universal slope method was proposed to predict their fatigue lives. However, the predictions have not been verified on other materials. Therefore, herein, low-cycle fatigue tests and finite-element analysis was performed on the carbon steel (STPT410) and stainless-steel (SUS304) elbows. The low-cycle fatigue life of SUS304 was 3 to 4 times longer than that of STPT410. The analytical results showed that the revised universal slope method can accurately predict the low-cycle fatigue lives of the SUS304 and STPT410 elbow pipes.