S0301-1-2 Effect of H_2 gas environment on low cycle fatigue damage accumulation and crack initiation of SUS304 stainless steel

Abstract

Notched compact tension specimens of SUS304 stainless steel (notch tip radius of 1mm and thickness of 6mm) were low cycle fatigued (stress ratio of -1) at RT in H_2 gas and in Pure air at 0.1Hz. Fatigue crack length of 2-3mm on the notch root surface was observed at number of cydes N=〜700 in Pure air and at N=〜200 in H_2. It is found that H_2 enhances the fatigue crack Initiation. The fatigue damage accumulation at midthickness of the specimens were observed by the recrystallization technique.