Implantation-Driven Tritium Permeation in Vanadium Alloy Fusion Reactors^a

The safety concerns resulting from tritium implantation into vanadium and vanadium alloys have been studied. Tests were conducted to measure the physical constants that determine permeation and inventory in these materials. Surface recombination coefficients, enhancement factors due to plasma sputtering, and the diffusion constants were measured. To determine the implications of these results, application was made to the TITAN-I fusion reactor design. For this design, the tritium permeation rate and inventory buildup in the first wall was calculated for a range of surface conditions on the coolant side.