Effect of initial dislocation density on hydrogen accumulation behavior in martensitic steel

Abstract We investigated hydrogen accumulation behavior of martensite structures with different initial dislocation densities. The hydrogen micro-print technique and microstructure observation revealed that the higher initial dislocation density facilitated hydrogen accumulation around prior austenite grain boundaries during deformation within the apparent elastic strain regime. In contrast, once deformation was applied to the plastic strain regime, hydrogen accumulation behavior did not change with initial dislocation density. Based on the obtained results, we concluded that transportation of hydrogen by dislocation motion played an important role on hydrogen accumulation around prior austenite grain boundaries.