Synthesis of Be-Ti-V ternary beryllium intermetallic compounds

Kim, Jae-Hwan; Nakamichi, Masaru

Beryllium intermetallic compounds (beryllides) such as BeTi and BeV are the most promising advanced neutron multipliers in demonstration power reactors. We developed a new combined plasma sintering and rotating electrode method for the fabrication of beryllide rods and pebbles. Previously, we prepared a beryllide pebble with a Be-7.7 at.% Ti composition as the stoichiometric value of the BeTi phase; however, BeTi and Be phases were present along with the BeTi phase that formed as the result of a peritectic reaction due to re-melting during granulation using the rotating electrode method. This Be phase was found to be highly reactive with oxygen and water vapor. Accordingly, to investigate the Be phase reduction and applicability for fabrication of electrodes prior to granulation using the rotating electrode method, Be-Ti-V ternary beryllides were synthesized using the plasma sintering method. Surface observation results indicated that increasing plasma sintering time and V addition led to an increase in the intermetallic compound phases compared with plasma-sintered beryllide with a Be-7.7 at.% Ti composition. Additionally, evaluation of the reactivity of samples with water vapor at high temperature revealed that specimens with larger fractions of Be phases experienced larger weight gains and H generation rates because of oxidation, as BeTi and BeV phases have a similar oxidation tendency.