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 312), 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 315
Diffusivity of 16O in V
Temperature (K) | D (m2/s) |
624 | 9.35 x 10-17 |
580 | 1.20 x 10-17 |
529 | 1.23 x 10-18 |
496 | 2.18 x 10-19 |