Design, synthesis and characterization of advanced tritium breeder: Li4Si1-xTixO4 ceramics

• Published in: Ceramics international 2021-05, Vol.47 (10), p.14178-14182
• Main Authors: Yan, Juemin, He, Nanlin, Chen, Xiaojun, Xiao, Chengjian, Zhao, Lin Jie, Gao, Tao
• Format: Article
• Language: English
• Subjects: Fabrication and characterization; Li4Si1-xTixO4; Tritium breeder materials
• ISSN: 0272-8842; 1873-3956
• DOI: 10.1016/j.ceramint.2021.02.004

Lithium orthosilicate (Li4SiO4) is an important tritium breeder for the fusion blanket concept. It was selected as the first candidate in China's test blanket model. In this study, in order to improve the thermal conductivity and mechanical properties of Li4SiO4, titanium was chosen to replace the silicon in it. This is because Ti has large atomic radius and the same charge as that of silicon. The fabrication and characterization of Li4Si1-xTixO4 solid solution was carried out. The Li4(Si,Ti)O4 powders were synthesised via a solid-state reaction, and the pebbles were fabricated using the freeze-drying method. The structure, morphology, thermal conductivity, and mechanical properties of the Li4(Si,Ti)O4 samples were analysed using X-ray diffraction, scanning electron microscopy-energy dispersive spectroscopy, a laser thermal conductivity meter, and a universal testing machine. Moreover, the thermal conductivity of Li4SiO4 improved significantly after Ti doping, and the mechanical properties of the Li4(Si,Ti)O4 pebbles sintered at 1000 °C were significantly better than those of Li4SiO4.