Hydrogen permeation through materials is one of the major problems in the fusion reactor design. In this study, hydrogen permeabilities of nickel and Hastelloy X were measured with a permeation method.
For nickel, the dependence of hydrogen permeability on hydrogen pressure and sample thickness was investigated systematically, and for Hastelloy X, the effects of sample treatments, mainly heat treatment, were studied.
Main results are as follows:
(1) Hydrogen permeability in nickel was obtained within the temperature range of 473 to 973 K, the hydrogen pressure range of 3.4×10
2 to 8.67×10
4 Pa and the sample thickness of 0.20 to 0.80 mm, which is as follows:
(This article is not displayable. Please see full text pdf.)
(2) Because of the good reproducibility of the data, the effectiveness of the apparatus was established.
(3) It was confirmed that the bulk diffusion is the rate-limiting step of hydrogen permeation through nickel and the dissolution of hydrogen into nickel depends on Sieverts’ law.
(4) Within the temperature range of 673 to 873 K, hydrogen permeabilities of Hastelloy X were obtained as follows:
\
oindentFor a sample without heat treatment
(This article is not displayable. Please see full text pdf.)
\
oindentfor a sample heated at 1023 K for 30 h before measurements
(This article is not displayable. Please see full text pdf.)
\
oindentfor a sample heated at 1023 K for 100 h before measurements
(This article is not displayable. Please see full text pdf.)
(5) Activation energy of hydrogen permeation in Hastelloy X was increased by the heat treaments, and this was qualitatively explained connecting with some precipitates.
View full abstract