A hot-extraction high-vacuum technique, involving mass-spectrographic detection, was used to determine the H content of U alloys. The time-dependences of H evolution from the bulk and of surface contamination were sufficiently different to separate. During the transient temperature portion of the analysis, the H evolution rate from various alloys was strongly influenced by the solubility of H. The H content which was due to surface contamination was equal to about 0.5ppm[wt]. This limited the lower limit of detection, for bulk H, to 0.05ppm[wt]. Diffusion data for H in U alloys were deduced from the H evolution rates (tables 175 to 177).
G.L.Powell, J.B.Condon: Analytical Chemistry, 1973, 45[14], 2349-54
Table 175
Diffusivity of H in U
T (C) | H (ppm[wt]) | H Evolution Rate (/s) | D (cm2/s) |
441 | 7.4 | 2.17 x 10-3 | 3.2 x 10-6 |
514 | 7.4 | 5.78 x 10-3 | 8.5 x 10-6 |
628 | 7.4 | 2.56 x 10-2 | 3.7 x 10-5 |
742 | 7.7 | 4.17 x 10-2 | 6.1 x 10-5 |
870 | 7.7 | 8.00 x 10-2 | 1.2 x 10-4 |
977 | 7.7 | 1.10 x 10-1 | 1.6 x 10-4 |
514 | 8.4 | 5.56 x 10-3 | 8.1 x 10-6 |
628 | 8.4 | 2.94 x 10-2 | 4.3 x 10-5 |
742 | 9.1 | 4.26 x 10-2 | 6.3 x 10-5 |
870 | 9.1 | 7.69 x 10-2 | 1.1 x 10-4 |
977 | 8.8 | 1.05 x 10-1 | 1.5 x 10-4 |
Table 176
Diffusivity of H in U-0.75wt%Ti
T (C) | H (ppm[wt]) | H Evolution Rate (/s) | D (cm2/s) |
555 | 11.2 | 2.0 x 10-3 | 2.0 x 10-5 |
640 | 11.0 | 3.7 x 10-3 | 3.7 x 10-5 |
730 | 4.7 | 6.1 x 10-3 | 6.2 x 10-5 |
820 | 10.9 | 1.37 x 10-2 | 1.4 x 10-4 |
900 | 52 | 1.72 x 10-2 | 1.8 x 10-4 |
900 | 48 | 1.82 x 10-2 | 1.9 x 10-4 |
990 | 8.3 | 2.04 x 10-2 | 2.1 x 10-4 |
990 | 7.5 | 2.04 x 10-2 | 2.1 x 10-4 |
Table 177
Diffusivity of H in U-7.5Nb-2.5wt%Zr
T (C) | H (ppm[wt]) | H Evolution Rate (/s) | D (cm2/s) |
1000 | 35 | 1.50 x 10-2 | 9.8 x 10-5 |
1000 | 23 | 1.38 x 10-2 | 9.0 x 10-5 |
1000 | 35 | 1.16 x 10-2 | 7.6 x 10-5 |
2000 | 8.0 | 1.50 x 10-2 | 9.8 x 10-5 |
1000 | 17 | 1.43 x 10-2 | 9.3 x 10-5 |
1000 | 17 | 1.36 x 10-2 | 8.9 x 10-5 |
1000 | 27 | 1.61 x 10-2 | 1.1 x 10-4 |
1000 | 15 | 1.31 x 10-2 | 8.6 x 10-5 |
900 | 29 | 1.20 x 10-2 | 7.8 x 10-5 |
800 | 29 | 9.30 x 10-3 | 6.1 x 10-5 |
475 | 8.7 | 4.70 x 10-3 | 7.7 x 10-6 |
370 | 9.2 | 4.00 x 10-3 | 6.5 x 10-6 |
610 | 8.1 | 1.81 x 10-2 | 3.0 x 10-5 |
730 | 7.0 | 2.59 x 10-2 | 4.2 x 10-5 |
830 | 6.0 | 3.57 x 10-2 | 5.8 x 10-5 |
continued
Table 177 (continued)
Diffusivity of H in U-7.5Nb-2.5wt%Zr
T (C) | H (ppm[wt]) | H Evolution Rate (/s) | D (cm2/s) |
920 | 8.8 | 4.17 x 10-2 | 6.8 x 10-5 |
1000 | 7.0 | 4.34 x 10-2 | 7.1 x 10-5 |
1050 | 8.5 | 4.76 x 10-2 | 7.8 x 10-5 |
425 | 27 | 6.70 x 10-3 | 1.1 x 10-5 |
530 | 33 | 7.00 x 10-3 | 1.2 x 10-5 |
645 | 28 | 1.19 x 10-2 | 1.9 x 10-5 |
775 | 32 | 3.00 x 10-2 | 4.9 x 10-5 |
860 | 26 | 4.35 x 10-2 | 7.1 x 10-5 |