A double-cell electrochemical technique was used to study H permeation in amorphous alloys. The H diffusivity versus H-content relationships were determined for various alloys (table 28). In each alloy, the H diffusivity increased markedly with increasing H concentration. This implied that there existed a broad range of energy states for H incorporation in the amorphous material. A key experimental feature was the sputter-deposition of a thin passivating surface film immediately after the sputter-deposition of Cu-Ti films.
Hydrogen Permeation in Amorphous Cu-Ti and Pd-Si Alloys. Y.S.Lee, D.A.Stevenson: Journal of Non-Crystalline Solids, 1985, 72[2-3], 249-66
Table 23
Diffusivity of H2 in Cu-Pd Alloys at 25C
Cu(at%) | Pressure(atm) | Phases Present | D(cm2/s) |
44.7 | 0 | α, β | 1.4 x 10-6 |
44.7 | 5 | α, β | 9.4 x 10-6 |
44.7 | 120 | α, β | 2.5 x 10-5 |
47.8 | 0 | α, β | 9.0 x 10-6 |
47.8 | 5 | α, β | 2.3 x 10-6 |
47.8 | 120 | α, β | 5.3 x 10-5 |
50.1 | 0 | α, β | 1.4 x 10-5 |
50.1 | 5 | α, β | 4.3 x 10-5 |
50.1 | 120 | β | 5.6 x 10-5 |
52.5 | 0 | α, β | 4.3 x 10-5 |
52.5 | 5 | β | 5.4 x 10-5 |
52.5 | 6.7 | β | 4.9 x 10-5 |
55.4 | 0 | β | 4.3 x 10-5 |
55.4 | 5 | β | 4.6 x 10-5 |
57.1 | 0 | β | 4.4 x 10-5 |
57.1 | 5 | β | 5.2 x 10-5 |
Table 24
Parameters for H Diffusion in Disordered Cu3Pd
Temperature (C) | Do (cm2/s) | E (kcal/g-atom) |
300-410 | 1.80 x 10-3 | 8.50 |
480-700 | 2.80 x 10-3 | 9.65 |
Table 25
Parameters for H Permeation in Disordered Cu3Pd
Temperature (C) | Po (cm mm/s atm½) | E (kcal/g-atom) |
300-410 | 1.06 x 10-2 | 7.77 |
480-700 | 2.15 x 10-2 | 8.30 |
Table 26
Parameters for H Diffusion in Ordered Cu3Pd at 300 to 400C
Annealing Time at 400C (h) | Do (cm2/s) | E (kcal/g-atom) |
20 | 5.30 x 10-4 | 7.75 |
45 | 3.35 x 10-4 | 7.30 |
70 | 3.35 x 10-4 | 7.30 |
Table 27
Parameters for H Permeation through Ordered Cu3Pd at 300 to 400C
Annealing Time(h) at 400C | Po (cm mm/s atm½) | E (kcal/g-atom) |
20 | 2.15 x 10-2 | 8.30 |
45 | 1.60 x 10-2 | 8.00 |
70 | 1.60 x 10-2 | 8.00 |
Table 28
Parameters for H Diffusion in Cu-Ti Amorphous Alloys
Material | H/M | Do (cm2/s) | E (kcal/mol) |
Cu48Ti52 | 0.13 | 9990 | 18.6 |
Cu48Ti52 | 0.22 | 185 | 15.6 |
Cu48Ti52 | 0.28 | 0.78 | 14.8 |
Cu48Ti52 | 0.36 | 0.22 | 13.6 |