Permeation time-lag methods were used to determine the diffusivity of H at temperatures ranging from 200 to 300C. The results could be described by:

D (cm2/s) = 1.06 x 10-2 exp[-9.18(kcal/mol)/RT]

Properties of Hydride-Forming Metals and of Multilayer Hydrogen Permeation Barriers. W.G.Perkins, D.R.Begeal: Berichte der Bunsengesellschaft für Physikalische Chemie, 1972, 76[8], 863. See also: J.W.Guthrie, L.C.Beavis, D.R.Begeal, W.G.Perkins: Journal of Nuclear Materials, 1974, 53, 313-22