抄録
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.
