Abstract
We have investigated the influence of 101 mass ppm hydrogen content on the mechanical behavior of an austenitic Fe30Mn6.5Al0.3C (wt.%) low-density steel. The steel exhibits high hydrogen embrittlement resistance, accompanied by a moderate increase in strength (yield stress increase of 10%) and ductility (increase in elongation to fracture of ~ 8%). We find that hydrogen influences the deformation
behavior by promoting deformation mechanisms associated with inhomogeneous plasticity. These processes are ascribed to hydrogen-induced effects on dislocation plasticity, resulting in macroscopic kink bands, sub-micron localized strain gradients, and localized shear at cell blocks. The contribution of these processes to the HE resistance of the steel is discussed.