Elemental development of beryllide electrode for pebble production by rotating electrode method

Beryllide (Be12Ti) is being considered one of the promising candidates for advanced neutron multipliers. In order to realize the pebble production, a vacuum casting process has to be applied. In the present study, an elemental technology to fabricate beryllide rods by a vacuum casting was developed. There were two major technical subjects to realize this process. The first was to identify a furnace material that shows minimum chemical reaction with beryllide. Another was to develop a procedure to cast durable ingot without any shrinkages and cracks. Reactivity between Be12Ti melt and refractory materials such as CaO, MgO and BeO was tested. It was clarified that the BeO crucible had less reactivity with melt and no contamination. Casting tests with a MgO cylindrical mold in a vacuum chamber revealed that the mold dimension was critical to minimize shrinkages and cracks. From this study, elemental technologies to be developed were made clear.