1031 高温高圧水素雰囲気で使用される圧力容器用鋼材の鋼中水素による脆化

抄録

Large 3.5T-CT specimens were hydrogen charged in huge autoclave and crack growth tests were carried out in order to clarify the characteristics of hydrogen embrittlement due to absorbed hydrogen in steel. It was shown that absorbed hydrogen in the 3.5T-CT specimen remained for much longer period of time than 1.0T-CT specimen under exposure at room temperature air. The long-term tests developed under slow rising load reveals the fundamental crack growth characteristics. It was shown that when hydrogen is introduced in temper embrittled steel, the susceptibility to fast fracture significantly increases. K_<IC-H>; a stress intensity factor where crack growth rate shows rapid increase, was turned out to be lower than K_<IC>(H-free). Also, those temper + hydrogen effect at elevated temperatures are investigated.