Development of Lithium Titanate Ceramic for the Test Blanket Module (TBM) in Fusion Reactor

Abstract

Lithium-based ceramic, Li2TiO3, is being considered as promising solid breeder materials in the tritium breeding blanket of thermonuclear fusion reactors, because of its reasonable lithium atom density, prominent tritium release rate at low temperatures between 200 and 400oC, its low activation characteristics, low thermal expansion coefficient, high thermal conductivity. For tritium recovery purpose samples having 85-90% of true density with open porosity (around 5%) is required. Uniform small grain size distribution (having diameter between 2-4μm) is preferable as activation energy for tritium diffusion through grain is higher compared to grain boundary. Solid state method requires higher calcination temperature, producing coarser particle and impurity, which adversely affects in achieving high sintered density (above 85% of theoretical density) and forms large grain size with entrapped closed pore inside the grain.