Hydrogen retention behavior of beryllides as advanced neutron multipliers

Beryllium intermetallic compounds (beryllides) are the most promising candidate materials for use as advanced neutron multipliers in future fusion reactors because of their low swelling and high stability at high temperatures. Recently, beryllium-titanium beryllide pebbles such as Be12Ti have been successfully fabricated using a novel granulation process. In this study, the fundamental aspects of the behavior of hydrogen isotopes in Be12Ti pebbles were investigated via thermal desorption spectroscopy and transmission electron microscopy. In addition, atomistic calculations using first principles electronic-structure methods were applied to determine the solution energy of hydrogen in Be12Ti. The results showed simpler and weaker hydrogen-trapping efficiency for Be12Ti than for pure Be.