[1G05-07] Tritium Permeation

[1G06] Oxidation behavior of Inconel 600 under high temperature, high pressure water environment and its effect on tritium permeation

*Azusa Matsumoto¹, Yuji Hatano¹ (1. University of Toyama)

Keywords:tritium, permeation, Inconel, steam, oxide layer

We have examined tritium (T) permeation through Inconel 600 in high temperature water and found that the permeation rate increased with H₂ addition and decreased with O₂ addition by a factor of 10. To clarify the underlying mechanisms, the surfaces of Inconel 600 samples were analyzed after exposure to water at 280 ℃ for 14 or 28 hours. The oxide film thickness was 30-40 nm without additive gas, 20-30 nm with H₂, and 50-100 nm with O₂. The oxide film thickness changed just by a factor of ~2; the change in T permeation rate cannot be explained by that in oxide thickness. It appears the change in HT partial pressure also contributed to the change in permeation rate.