Effects of multi-ion irradiation on microstructural changes in lithium titanate

The irradiation behavior of Li2TiO3 under a fusion reactor environment was simulated by simultaneous irradiation of Li2TiO3 by the triple ion beams and the respective single ion beams of O2+, He+ and H+. The microstructural changes in Li2TiO3 caused by the irradiation were measured by FT-IR photoacoustic spectroscopy. The results suggest that the amount of TiO2 formed is proportional to the dpa and that the method of irradiation does not affect the dependence of formation of TiO2. On the other hand, the amount of defects and/or radiolytic products generated by irradiation, which is considered to trap hydrogen near the surface, is found to be affected by the method of irradiation. Such phenomena are believed to affect the tritium release behavior from Li2TiO3, and durability of Li2TiO3 and compatibility of Li2TiO3 with other components of the breeder blanket such as structural materials in the fusion reactor system under operation.