Enhancing properties of Li2TiO3/Li4SiO4 tritium breeding ceramics by chitosan addition

Abstract

Li2TiO3/Li4SiO4 ceramics have been regarded as promising tritium breeders due to their numerous merits. In this work, chitosan was employed as an effective binder to provide adhesion of Li2TiO3 particles to Li4SiO4 particles, resulting in Li2TiO3/Li4SiO4 ceramics with improved performance. Chitosan could be removed during the sintering process and had little influence on the phase composition. The resulting Li2TiO3/Li4SiO4 ceramics had higher density (92.5%T.D.), greater crushing loads (115.2 ± 20.8 N) and superior thermal properties (3.61 W/m∙K) when compared to the samples prepared without chitosan. SEM analyses displayed a dual-scale structure and the inter- and trans-granular fracture mode. Thermal cycling tests revealed that the phase composition was stable but the crushing load fell slightly. The crushing load remained at 92.4 ± 17.1 N after 12 cycles. Overall, chitosan plays an important role in the amelioration of interface combination between Li4SiO4 and Li2TiO3, and thus significantly improve density, crushing load and thermal conductivity of Li2TiO3/Li4SiO4.

Keywords

• Tritium breeding materials
• Li2TiO3/Li4SiO4 ceramics
• Crushing load
• Thermal conductivity
• Thermal cycling stability