The boundary conditions for electrochemical permeation through annealed α-phase material were considered, and the diffusion coefficients were measured at between 278 and 333K. In permeation experiments, the changes in electrode potential and current density at the cathodic surface corresponded to changes in dissolved H content and H entry flux at the cathodic surface, respectively. It was found that the results for diffusion which was free of trapping and surface effects could be described by the expression:

D (m2/s) = 2.40 x 10-7 exp[-21.6(kJ/mol)/RT]

Boundary Conditions in Electrochemical Measurements of Diffusion Coefficients of Hydrogen in α-Palladium. H.Hagi: Journal of the Japan Institute of Metals, 1989, 53[8], 753-8