Effect of internal hydrogen on very high cycle fatigue of precipitation-strengthened steel SUH660. (January 2015) - Wu, Hao
Highlights: We investigated the effect of internal hydrogen on very high cycle fatigue life. The influence of hydrogen was discussed on the initiation lives of all cracks. New crack initiation life dominates very high cycle fatigue life of SUH660 steel. New crack initiation near the temporarily arrested crack dominates the fatigue life. We found the hardness change of SUH660 steel after hydrogen charging. Abstract: The fatigue life of SUH660 steel is dominated by crack initiation in the region of very high cycle fatigue owing to the new crack initiation behavior near the tip of temporarily arrested crack. The effect of internal hydrogen on very high cycle fatigue life is investigated focused on crack initiation life via fatigue and Vickers hardness tests. Hydrogen inhibits cracks initiation, and accelerates the increase in crack initiation lives with decreasing stress in low and medium hardness zones. Hydrogen increases the hardness in low and medium hardness zones. Hydrogen extends new crack initiation lives and causes longer very high cycle fatigue life.