A study was made of the kinetics of the H take-up of cylindrical and spherical Ni specimens. At 200 to 600C, the data obeyed:

D (cm2/s) = 5.4 x 10-3 exp[-0.41(eV)/kT]

P.Combette, P.Azou: Comptes Rendus, 1969, 268[8], 677-80