Effect of hydrogen on the dislocation structure of deformed nickel

The present note reports a part of the continuing study of the effects of H on the dislocation and fracture behavior of Ni. The dislocation structures produced in Ni by deforming in H2 and He gas environments and 0.20 m/m were compared using transmission electron microscopy. The specimens were those which exhibited H solution softening at low strain rates when tested in an H2 atmosphere. The question addressed is whether specimens tested at the same strain rates and to similar total strains in different atmospheres exhibit different dislocation structures