Hydrogen compatibility of HT-9 martensitic stainless steel☆

Abstract The hydrogen compatibility of the alloy HT-9 is addressed. The results of tensile tests performed on specimens both in a gaseous hydrogen environment and after cathodic charging are described. The findings show that there is only a small effect of hydrogen (at the levels tested) on the ductility of quenched-and-tempered HT-9. However, larger reductions in ductility are observed for the as-quenched specimens. It is also shown that increasing the hydrogen concentration and the strength level generally increases the likelihood of surface crack initiation which is an indication of a decrease in damage tolerance.