Acta Metallurgica Sinica (English Letters) ›› 1997, Vol. 10 ›› Issue (3): 206-112.

• Research paper • Previous Articles     Next Articles

EFFECT OF MICROSTRUCTURE ON HYDROGEN DAMAGE OF JBK-75 PRECIPITATE-STRENGTHENED AUSTENITIC STEEL

L.M Ma;G.J. Liang;CG. Fan;and Y Y Li(Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110015, China)   

  • Received:1997-06-25 Revised:1997-06-25 Online:1997-06-25 Published:2009-10-10

Abstract: 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.

Key words: hydrogen damage, microstructure, precipitate-strengthened austenitic steel