Reactivity of plasma-sintered beryllium–titanium intermetallic compounds with water vapor

Beryllium–titanium intermetallic compounds (beryllides) are candidates for advanced neutron multipliers in water-cooled solid breeder demonstration (DEMO) reactor. In contrast to beryllium, which is highly reactive with water vapor above 873 K, the beryllide is considerably more stable with much lower hydrogen-gas-generation rates. To investigate the effect of phase compositions on the reactivity with water vapor, the beryllides were plasma-sintered for different times to produce different phase compositions. They were examined by thermogravimetric analysis and the H2-generation rate was measured at 1273 and 1473 K for 24 h under Ar gas containing 1% H2O. The resulting weight gain of the beryllides under 1% H2O was in good agreement with previous results showing that with an increase in the area fraction of Be, the oxidation resistance under Ar gas containing 1% H2O decreases. The result of the H2-generation rate at 1273 K demonstrates that the larger the fraction of Be, the higher the H2-generation rate. It is clear that the Be phase in the plasma-sintered beryllides attributes to an increase in H2-gas generation. We report here on the effect of phase compositions on reactivity with water vapor of the plasma-sintered beryllides.