Tritium diffusion in single crystals of rutile was measured between 155 and 300C. The diffusivities were deduced from concentration profiles obtained from microdensitometer traces of autoradiographs generated by β-decay of the tritium. The diffusivity was anisotropic, with estimated diffusivities given by:
a-axis: D(cm2/s) = 2.7 x 10-6exp[-13.100(kcal/mol)/RT]
c-axis: D(cm2/s) = 7.5 x 10-6exp[-9.040(kcal/mol)/RT]
Diffusion of Tritium in Rutile (TiO2). Caskey, G.R.: Materials Science and Engineering, 1974, 14[2], 109-14
Table 11
Diffusion coefficient for T diffusion parallel
to the c-axis of rutile (dominant mechanism)
Temperature (C) | Equilibrium O Pressure (atm) | D (cm2/s) |
254 | 7 x 10-39 | 5.35 x 10-10 |
304 | 1 x 10-34 | 2.24 x 10-9 |
350 | 3 x 10-31 | 7.96 x 10-9 |
401 | 3 x 10-28 | 2.18 x 10-8 |
406 | 3 x 10-28 | 2.38 x 10-8 |
500 | 1 x 10-23 | 1.20 x 10-7 |
504 | 4 x 10-16 | 1.18 x 10-7 |
509 | 2 x 10-29 | 7.94 x 10-8 |
510 | 1 x 10-23 | 1.06 x 10-7 |
602 | 7 x 10-20 | 3.29 x 10-7 |
700 | 5 x 10-17 | 9.60 x 10-7 |