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) = 6.06 x 10-3 exp[-11.0(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
Table 77
Parameters for H Diffusion in 34KhN3M Steel with or without 0.5wt%Pd
Pd (wt%) | Temperature (C) | Do (cm2/s) | E (kcal/mol) |
0 | 300-600 | 4.7 x 10-4 | 1.6 |
0 | 750-1000 | 1.6 x 10-3 | 7.5 |
0.5 | 300-600 | 5.4 x 10-4 | 2.0 |
0.5 | 750-1000 | 1.5 x 10-3 | 7.2 |