Tritium release behavior of Li2TiO3 and 2Li2TiO3-Li4SiO4 biphasic ceramic pebbles fabricated by microwave sintering

Abstract

Abstract Li2TiO3-Li4SiO4 biphasic ceramic is considered as an advanced tritium breeder material for its potential to combine the advantages of both Li2TiO3 and Li4SiO4. In this study, Li2TiO3 and 2Li2TiO3-Li4SiO4 biphasic pebbles with promising properties were fabricated by microwave sintering. The 2Li2TiO3-Li4SiO4 biphasic pebbles displayed porous structure with a grain size of 170 nm. Tritium release behavior for the microwave sintered ceramic breeder pebbles was investigated. It was found that the microwave sintered Li2TiO3 pebbles show the same release behavior with that of conventional sintered pebbles due to the similar microstructure and density properties. Besides, the tritium release results indicated that high closed porosity may lead to the increase of release temperature. The 2Li2TiO3-Li4SiO4 biphasic ceramic pebbles hold satisfactory tritium release behavior with a low release temperature around 450 °C. According to the tritium release results, it could be concluded that the interfaces between Li2TiO3 and Li4SiO4 can improve the tritium release behavior by promoting the surface reaction.