Reaction sintering of a rock salt structured Li4WO5 ceramic and its microwave dielectric properties

Rock salt structured Li4WO5 ceramics were prepared by the reaction sintering method. Without calcination, a mixture of Li2CO3 and WO3 were sintered directly. XRD shows that a single orthorhombic Li4WO5 phase was obtained throughout the sintering temperature range 870-910 A degrees C. Dense ceramic with a high relative density similar to 94.2% was achieved through reaction sintering at 880 A degrees C. Excellent microwave properties with epsilon (r) = 9.1, Q x f = 43,000 GHz, and tau (f) = - 3 ppm/A degrees C were obtained. In contrast with the conventionally sintered ceramics, it should be noted that the reaction sintered samples have a higher permittivity and quality factor. These results show that the reaction sintering can enhance the densification of Li4WO5, which in turn would improve the dielectric performances.