Samples which consisted of a Pd over-layer, sputter-deposited FeTi0.9 film, and a Pd plate were studied at temperatures of between 473 and 773K. The H diffusivity was deduced via a permeation theory for bi-layer composites. The film was amorphous at temperatures of up to 723K. The effective H diffusion coefficient of the sample was almost equal to that of Pd, and it was therefore impossible to estimate the H diffusion coefficient for the amorphous film. The permeability and diffusivity markedly decreased after crystallization of the film. The calculated H diffusion coefficient in the crystalline material exhibited a small temperature dependence:
D (m2/s) = 2.84 x 10-10 exp[-19.0(kJ/mol)/RT]
This was attributed to short-circuit diffusion through defects such as grain boundaries.
M.Amano, K.Nakamura: Transactions of the Japan Institute of Metals, 1988, 29[4], 308-13
Table 201
Diffusion of 14C in Fe-V
V (at%) | Temperature (K) | D (m2/s) |
0 | 1010.4 | 1.49 x 10-10 |
0.1 | 990.0 | 5.46 x 10-11 |
0.1 | 1136.5 | 5.14 x 10-10 |
0.5 | 990.0 | 1.27 x 10-11 |
0.5 | 1136.5 | 2.07 x 10-10 |
2.45 | 900.1 | 6.27 x 10-13 |
2.45 | 998.6 | 5.23 x 10-12 |
2.45 | 1141.8 | 6.98 x 10-11 |
2.45 | 1222.4 | 1.99 x 10-10 |
2.45 | 1325.3 | 8.76 x 10-10 |