Ceramics-Silikáty 58 (2) 123-131 (2014)

CHARACTERIZATION OF COMPOSITES OF BERYLLIA AND LITHIUM-TITANATE PRODUCED BY SOL-GEL ROUTE

Beryllium oxide (BeO) can be used as a constituent for lithium titanate (Li₂TiO₃) based composite material for neutron multiplication and breeding in International Thermonuclear Experimental Reactor (ITER) having tritium breeding ratio (TBR) more than 1.1. In the present investigation, we report the synthesis of various volume ratios of BeO-Li₂TiO₃ composites. The characterization showed that the coefficient of thermal expansion values for the composites are half of that of the Lithium titanate. The novel composites showed improved thermal conductivity compared to Li₂TiO₃. The thermal conductivity at 672 K which is close to the operating temperature is 47 W/mK which is ~17 times that of Li₂TiO₃. So there is a large improvement in thermal conductivity by use of this composite instead of use of Li₂TiO₃ and metallic Be separately. The impedance measurement showed that with the addition of BeO, there is reduction in electrical conductivity which is better to be used in the fusion reactor. The composites are found to have better modulus properties in comparison to Li₂TiO₃. So, from the present investigation, it could be concluded that it is possible to achieve tritium breeding ratio (TBR) more than 1.1 by optimizing the BeO and Li₂TiO₃ ratio with better properties.

Keywords: Beryllium oxide, Lithium titanate, ITER, Tritium breeding ratio, Neutron multiplier, Neutron breeder