Cyclic plastic deformation behaviour of Ni single crystals oriented for single slip as a function of hydrogen content

Ni single crystals oriented for single slip, exhibit well defined cyclic stress-strain curves at room temperature, corresponding, partly to the formation of persistent slip bands in a given plastic strain range. The aim of the paper is to study the influence of hydrogen on the cyclic plastic behaviour of such crystals. Tests on pre-charged specimens show a decrease of the saturation stress, in comparison with pure nickel samples. Such effects are discussed in terms of hydrogen-dislocation interactions, and reduced cross slip ability in presence of hydrogen.