Fabrication of Li2TiO3 Ceramic Pebbles by Gelcasting Method

Lithium titanate (Li2TiO3) ceramic pebbles are considered to be a candidate material of the tritium breeders for fusion reactor from the viewpoints of good tritium recovery, chemical stability and other excellent properties. In this study, fine grain and pure Li2TiO3 powders were prepared by solid-state method at 700 degrees C using TiO2 and Li2TiO3 as raw materials. Li2TiO3 pebbles were prepared by gel-casting method using acrylamide (AM) as organic monomer, N,N'-methylenebisacrylamide (MBAM) as cross-linker, ammonium citrate as dispersant, and isooctyl alcohol as defoamer. The effect of solid content, dispersant, pH and the ball milling time on the fluidity and dispersion of ceramics slurry were investigated, and the effects of sintering temperature and holding time were also discussed in present study. The sintered ceramic pebbles with diameter of 1.0 mm show a smooth surface, uniform grain size and perfect sphericity. The Li2TiO3 ceramic pebbles sintered at 1250 degrees C for 8 hours had the highest density (>90% of theoretical density) and crush strength.