The gas permeation method, and quadrupole mass spectrometry, were used to monitor the super-diffusion of H under the influence of a stress which was applied to polycrystalline V specimens with electroplated Pd films. It was found that the effective diffusion coefficients (table 259), measured under an applied stress of more than 18MPa at a temperature of 404 or 426K, increased steeply to values which were 6 to 10 times higher than those under no applied stress. It was also noted that the H solubility decreased by a factor of about 1/3. It was suggested that super-diffusion involved the hopping motion of 4T-type H atoms.

M.Kano, N.Kagawa, S.Koike, K.Furuya, T.Suzuki: Acta Metallurgica, 1988, 36[6], 1553-62

Table 259

Diffusion of H in V