Tritium and lithium diffusion mechanism in neutron-irradiated β-⁶LiAl

In the Japan Atomic Energy Research Institute (JAERI), technology for tritium production by use of ⁶Li-Al alloy has been developed with the aim of furnishing tritium for fusion research. The alloy contains β-phase, i.e., intermetallic compound β-LiAl, which has a large influence on the tritium behaviour in ⁶Li-Al alloy. Since β-LiAl has a unique crystal structure and a large amount of Li vacancy at room temperature, the tritium behaviour in β-LiAl is affected by the defect structure and the lithium diffusion. In this paper, on the basis of a simultaneous measurement of tritium release rate and electrical reseistivity, it is suggested that the tritium diffusion has a strong correlation with the lithium diffusion in the neutron-irradiated β-⁶LiAl.