Retention and release of tritium in BC irradiated as control rod of fast breeder reactor

Donomae, Takako  ; Ito, Masahiko*

The release and retention of tritium generated in FBR control rods of BC irradiated to high fluence were investigated for temperatures up to 800C. The amounts of tritium retention were expressed as a function of fluence, and the results agreed approximately with the theoretically calculated values. In addition, the amounts of tritium could be approximately evaluated by simply measuring the radioactivity of Mn using germanium semiconductor detector, which is generated from Fe impurity in BC. The temperature at which the tritium begins to be released from BC was investigated by heating a specimen at a constant temperature increasing rate. It was found in this experiment that the tritium begins to be released from BC at 400C. From the results of this isochronal heating, diffusion coefficients of tritium in BC were derived.