Effects of γ， η precipitates and grain size on hydrogen damage (HD) of JBK-75 precipitate-strengthened austenitic steel were examined using the method of high-pressure thermal hydrogen charging and tensile tests. T...Effects of γ， η precipitates and grain size on hydrogen damage (HD) of JBK-75 precipitate-strengthened austenitic steel were examined using the method of high-pressure thermal hydrogen charging and tensile tests. The hydrogen content in the charged specimens was 25.2 wppm. At the condition of η phase-free precipitating, the HD of the steel increased with increasing γ size, fine spherical γ dispersively dis-tributed was beneficial to improve the hydrogen-resistant property. η-phae precipitated at grain boundary increased HD tendency, while intragranular cellular η had less effect on it. Fine austenitic gruin Aize was beneficial to decrease the HD. At the condition of η phase-free precipitating, both hydrogen changed and uncharyed specimens of the steel fractured in ductile transgranular mode, whilst hydrogen promoted the intergranular fracture when obvious η precipitates were found.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.12172123)the Natural Science Foundation of Hunan Province(Grant Nos.2022JJ20001 and 2021JJ40032)+3 种基金the Science and Technology Innovation Program of Hunan Province(Grant No.2022RC1200)the Natural Science Foundation of Changsha City(Grant No.kq2202139)the National Science Foundation(Grant Nos.DMR-1611180 and 1809640)the US Army Research Office(Grant Nos.W911NF-13-1-0438 and W911NF-19-2-0049).
文摘Effects of γ， η precipitates and grain size on hydrogen damage (HD) of JBK-75 precipitate-strengthened austenitic steel were examined using the method of high-pressure thermal hydrogen charging and tensile tests. The hydrogen content in the charged specimens was 25.2 wppm. At the condition of η phase-free precipitating, the HD of the steel increased with increasing γ size, fine spherical γ dispersively dis-tributed was beneficial to improve the hydrogen-resistant property. η-phae precipitated at grain boundary increased HD tendency, while intragranular cellular η had less effect on it. Fine austenitic gruin Aize was beneficial to decrease the HD. At the condition of η phase-free precipitating, both hydrogen changed and uncharyed specimens of the steel fractured in ductile transgranular mode, whilst hydrogen promoted the intergranular fracture when obvious η precipitates were found.
