241 軸受鋼の動的ねじり-静的圧縮荷重下での疲労挙動に及ぼす水素の影響(OS8-2 水素環境が金属強度特性に及ぼす影響,OS8 水素環境が金属強度特性に及ぼす影響)
詳細
Fatigue tests were conducted on bearing steel, JIS-SUJ2 (SAE 52100) under cyclic torsion with compressive mean stress to simulate the stress condition of rolling bearing. Mode II fatigue cracks initiated and propagated along the axial direction of specimen in hydrogen-charged and uncharged specimens. Fatigue life was shorter by factor of 1/3-1/10 in hydrogen-charged specimens than that of uncharged specimens. More cracks were observed at the final stage in hydrogen-charged specimens (N/N_f=0.97) than in uncharged specimens (N/N_f=0.96). It is presumed that the slip deformation on the surface of the specimen was restricted and localized by hydrogen.
