Scalable fabrication and deuterium release properties of Li2TiO3-Li2ZrO3 ceramic pebbles via centrifugal granulation

The Li 2 TiO 3 and Li 2 ZrO 3 ceramic pebbles are regarded as promising tritium breeder on account of their superb chemical stability, high tritium diffusion rates, and neutron multiplication potential of Zr, respectively. To integrate the advantages of these two materials, it is necessary to develop a composite such as Li 2 TiO 3 -Li 2 ZrO 3 , which is ideal for advanced fusion reactor designs. Up to now, fabricated biphasic ceramic pebbles generally suffer from low production yield, inadequate crushing load, and high cost, which restricts their application in practice. In this paper, biphasic Li 2 TiO 3 -Li 2 ZrO 3 tritium breeding pebbles with superior crushing strength are successfully fabricated employing the centrifugal granulation method by selecting the appropriate binder and controlling the growth rate. Moreover, by this technique, ceramic pebbles with wide diameter distribution can be obtained, which will help to improve the packing factor of pebble beds in the solid blanket. In addition, the composition, microstructure, and internal structure of the Li 2 TiO 3 -Li 2 ZrO 3 ceramic pebbles are thoroughly analyzed, respectively. The Li 2 TiO 3 -Li 2 ZrO 3 ceramic pebbles, after being sintered at 1100 °C, attained a high sphericity of 0.97, a superior crushing load of 67.6 N, and an optimum porosity of 9.75 % in the shell. Moreover, the Li 2 TiO 3 -Li 2 ZrO 3 ceramic pebbles also exhibit excellent deuterium release properties with the main form of HDO. The above results show that the centrifugal granulation method is not only applicable to the mass production of Li 2 TiO 3 -Li 2 ZrO 3 ceramic pebbles but also to other tritium breeders, which offers promising prospects for the development of advanced tritium breeding materials in the future.