Fabrication and Characterization of Li₂TiO₃ Pebbles by an Extrusion and Spherodization Technique for the Test Blanket Module in a Fusion Reactor

Lithium titanate breeder powder was prepared at low temperature by a solid-state mixing method. Pebbles were prepared by an extrusion and spherodization technique. The effect of binder content on separation of the extruded mass was studied. The influences of different cone mesh opening diameters (1.5, 1.0, and 0.5 mm) and spherodization speed were investigated to obtain small (0.5- to 1.5-mm) pebbles with small variations in size. It was found that Li₂TiO₃ could be sintered at low temperature (900°C for 6 h) with appreciable density (89%) and small grain size (1 to 3 μm) without significant closed porosity. The sphericity, pore size distribution, grain size, and crushing load strength of the sintered pebbles were also characterized. Their values were found to conform with the desired properties for use as a solid breeder.