Study of tritium retention in graphite by simulating first wall circumstances

Hydrogen retention property on isotropic graphite was studied by exposure with a high flux atomized D/T particles. From the analysis of thermal desorption spectra it is clarified that deuterium implanted to graphite existed in two different states: One was that in a trap site; the other was that of C-D bond. The amount of deuterium retained in graphite was in proportion to a half power of total incident fluence and no saturation was observed up to 1026 atoms.m-2. The total hydrogen isotope retention in the sample exposed to atomized D/T particles with total incident fluence of 1025 - 1026 atoms.m-2 were in the range of 1x1022-4x1022 atoms.m-2. 16 refs., 6 figs