Dielectric characteristics of (Mg1/2Co1/2)Al2O4 ceramics at microwave frequencies

The microwave dielectric properties and the microstructures of (Mg1/2Co1/2)Al2O4 ceramics prepared by conventional solid-state route have been studied. The dielectric constant values (ɛr) saturated at 8.3–8.7. The Q × f values of 4500–107,300 GHz can be obtained when the sintering temperatures are in the range of 1480–1600 °C. The temperature coefficient of resonant frequency τf was not sensitive to the sintering temperature. The ɛr value of 8.75, Q × f value of 107,300 GHz, and τf value of −54 ppm °C−1 were obtained for (Mg1/2Co1/2)Al2O4 ceramics sintered at 1600 °C for 4 h. For applications of high selective microwave ceramic resonator, filter and antenna, (Mg1/2Co1/2)Al2O4 is proposed as suitable material candidate.