The diffusivity of H in α-phase films was measured, at temperatures of between 278 and 323K, by using an electrochemical stripping method. The films were deposited onto Fe substrates by means of radio-frequency sputtering. The diffusion coefficients which were found for 0.00068 and 0.00136mm films were some 2 orders of magnitude lower than the values reported for bulk specimens. The results could be described by the expression:

D (m2/s) = 4.16 x 10-9 exp[-25.7(kJ/mol)/RT]

H.Hagi: Journal of the Japan Institute of Metals, 1989, 53[11], 1085-8