Fabrication and characterization of Li4SiO4 ceramic pebbles by wet method

Li4SiO4 (lithium orthosilicate) is an important tritium breeder for fusion blanket concept. In test blanket module (TBM) design of China, Li4SiO4 ceramic pebbles have been selected as the first candidate material of tritium breeders. The fabrication process and properties of the pebbles have been investigated. Wet method is used to fabricate Li4SiO4 ceramic pebbles. XRD results show that Li4SiO4 with a high phase purity has been prepared by wet method. SEM photographs indicate that the pebbles have porous structure and small grain size. Li4SiO4 ceramic pebbles, which were sintered at 1020 °C, have good properties, such as small diameter (0.5–0.8 mm), high density (over 80% TD), good sphericity (1.02) and large crush load (a.v, 20 N). The results show that Li4SiO4 ceramic pebbles can be successfully fabricated by wet method, under the appropriate conditions of solid/liquid ratio and sintering temperature.