Effects of hydrogen charging and deformation on tensile properties of a multi-component alloy for nuclear applications

In this study, the influence of hydrogen charging and deformation on the tensile behavior of a 60Fe–12Cr–10Mn–15Cu–3Mo multi-component alloy was investigated using electron microscopy and positron annihilation lifetime spectroscopy. The results show that hydrogen-induced vacancy clusters found in the electrochemically charged hydrogen specimens are responsible for crack initiation. Upon ingress to the microstructure, hydrogen promotes the formation of cell-structured dislocations that are beneficial for the improvement of tensile strength. In addition, hydrogen embrittlement can be mitigated by dislocations that can hinder hydrogen mobility in the deformed specimens.