Hardening effects in plastically deformed Pd with the addition of H

Well-annealed Pd and Pd–H alloys were subjected to tensile tests. It is found that the presence of H does not affect the yield strength but enhances the strain hardening of Pd remarkably. This is explained by a negligible solute drag effect of H on the movement of dislocations, and by H-induced enhanced multiplication of dislocations upon plastic deformation, respectively.