An investigation was made of the diffusion of H into steel specimens which had various structures (table 49), but the same composition (0.54C, 0.35Si, 0.65Mn), by using cathodic H charging in 5% H2SO4 solution at a current density of 0.2A/cm2.

I.Onishi, Y.Kikuta, T.Araki, F.Tanichi, T.Fujii: Yosetsu Gakkaishi, 1967, 36[11], 1188-93