Present status of beryllide R&D as neutron multiplier

Abstract Since 1997, beryllide application as the neutron multiplier has been proposed in Japan and preliminary investigations revealed that some beryllides such as Be 12 Ti have excellent properties compared with beryllium metal. Recently, several international R&D programs were performed. Some pebbles of modified Be 12 Ti that included the Be phase were obtained by the rotating electrode method. Basic characterization using HIPped Be 12 Ti has also been performed. Preliminary experiments indicate that compatibility with stainless steel and tritium breeder materials, deuterium release, natural oxidation and oxidations by steam interaction were better than the behavior of beryllium. Preliminary neutron irradiation effects were studied in JMTR and by charged particle irradiation. It was observed that Be 12 Ti has less radiation damage than beryllium. In a future experiment, Japanese Be 12 Ti samples will be included in a long European irradiation program on beryllium to produce up to 6000 appm He. This is an IEA collaborative experiment, to evaluate neutron irradiation effects.