A study was made of diffusion, in material of technical purity, by using electrolytic charging of the specimens, and serial sectioning analysis for H and D following diffusion annealing. The results (table 161) could be summarised by:
H (0 to 300C): D (cm2/s) = 5.0 x 10-4 exp[-0.159(eV)/kT]
D (0 to 400C): D (cm2/s) = 6.4 x 10-4 exp[-0.186(eV)/kT]
B.A.Merisov, G.J.Khadzhay, V.I.Khotkevich: Fizika Metallov i Metallovedenie, 1974, 37[5], 1090-2
Table 161
Diffusivity of H and D in Ta
Isotope | Temperature (C) | D (cm2/s) |
H | 0 | 5.6 x 10-7 |
H | 22 | 9.9 x 10-7 |
H | 23 | 1.04 x 10-6 |
H | 25 | 1.07 x 10-6 |
H | 30 | 1.04 x 10-6 |
H | 30 | 1.16 x 10-6 |
H | 46 | 1.36 x 10-6 |
H | 60 | 1.65 x 10-6 |
H | 77 | 2.20 x 10-6 |
H | 100 | 3.10 x 10-6 |
H | 125 | 5.7 x 10-6 |
H | 150 | 7.7 x 10-6 |
H | 175 | 7.8 x 10-6 |
H | 205 | 1.24 x 10-5 |
H | 225 | 1.11 x 10-5 |
H | 225 | 1.11 x 10-5 |
H | 250 | 1.33 x 10-5 |
H | 302 | 2.00 x 10-5 |
D | 0 | 2.4 x 10-7 |
D | 30 | 4.8 x 10-7 |
D | 46 | 8.9 x 10-7 |
D | 60 | 9.6 x 10-7 |
D | 77 | 1.13 x 10-6 |
D | 100 | 1.80 x 10-6 |
D | 125 | 2.9 x 10-6 |
D | 150 | 3.5 x 10-6 |
D | 175 | 5.4 x 10-6 |
D | 205 | 7.6 x 10-6 |
D | 225 | 8.0 x 10-6 |
D | 225 | 7.3 x 10-6 |
D | 250 | 1.06 x 10-5 |
D | 400 | 2.72 x 10-5 |