Diffusion behaviors of tritium formed in lithium-lead alloys by 14 MeV neutron irradiation

Tritium recovery experiments were performed with Li-Pb alloys irradiated with 14 MeV neutrons. The effects of temperature, alloy composition, and neutron fluence were observed on tritium recovery. Tritium was released mainly as HT from the alloy and its release rate was controlled by bulk diffusion in the alloy. From the chemical analysis of tritium species in the alloy, it was found that free tritium atoms in the T0 state diffuse more rapidly than the others such as tritide ions in the T- state. The diffusion mechanism for each species was discussed based on the obtained diffusion coefficients. It was also found that free tritium atoms might be trapped by radiation defects produced in the alloy. (orig.)