Tritium release from irradiated beryllium during and after surface oxidation

Beryllium will almost certainly be used for plasma-facing components and in the ITER blanket. Tritium, generated in the Be by neutrons, will make up most of the ITER tritium inventory. Computer models for predicting tritium release from beryllium in the first wall and blanket have not considered the effect of surface oxidation, although some reports say this is significant. The present work measures the tritium release rate from irradiated beryllium during and after oxidation by air and/or water vapour. The results help assess: (a) how leaks would affect the subsequent extraction of tritium from the blanket, and (b) the amount of tritium released from beryllium in the blanket, or from bulk beryllium in the first wall, during a loss-of-cooling accident. (authors)