Effect of CuO Addition on Microwave Dielectric Properties of 0.80Sm(Mg^sub 0.5^Ti^sub 0.5^)O3-0.20Ca^sub 0.8^Sr^sub 0.2^TiO3 Ceramics

The effects of CuO addition on phase composition, microstructure, sintering behavior, and microwave dielectric properties of 0.80Sm(Mg^sub 0.5^Ti^sub 0.5^)O3-0.20 Ca^sub 0.8^Sr^sub 0.2^TiO3(8SMT-2CST) ceramics prepared by a conventional solid-state ceramic route have been studied. CuO addition shows no obvious influence on the phase of the 8SMT-2CST ceramics and all the samples exhibit pure perovskite structure. Appropriate CuO addition can effectively promote sintering and grain growth, and consequently improve the dielectric properties of the ceramics. The sintering temperature of the ceramics decreases by 50°C by adding 1.00 wt.%CuO. Superior microwave dielectric properties with a [straight epsilon] ^sub r^ of 29.8, Q × f of 85,500 GHz, and τ ^sub f^ of 2.4 ppm/°C are obtained for 1.00 wt.%CuO doped 8SMT-2CST ceramics sintered at 1500°C, which shows dense and uniform microstructure as well as well-developed grain growth.[PUBLICATION ABSTRACT]