Development of a synthesis method of beryllides as advanced neutron multiplier for DEMO reactors

Advanced neutron multipliers with low swelling and high stability at high temperature are desired for pebble bed blankets, which will impact on the DEMO design features, especially blanket operating temperature. Among candidates for multiplier, beryllium intermetallic compounds (beryllides) are one of the most promising advanced neutron multipliers. In order to fabricate the beryllide pebble, beryllide with the shape of rod are necessary if a melting granulation method is applied. A plasma sintering method and a high-frequency heating method have been proposed as a new technique, because these methods are simple process and easy to control. A plasma sintering method for beryllide synthesis has been proposed as a new technique which uses a non-conventional consolidation process. The present paper describes beryllide synthesis results using this method for development of fabrication technique for a beryllide rod. It was clarified that the beryllide could be both synthesized and jointed with no variation of phase and hardness by the plasma sintering method. Additionally, trial synthesis of beryllide by a melting process using high-frequency heating was carried out. Although there were some pores in a melted ingot, beryllides could be also synthesized by this method.