Abstract
In this study, the effects of Co2+ substitution for Mg2+ on the sintering behavior and dielectric properties of Ca(Mg0.92−xCoxAl0.08)(Si0.96Al0.04)2O6 ceramics were investigated. The main phase transformed from Ca(Mg,Co,Al)(Si,Al)2O6 to CaCoSi2O6 as the x value varied from 0.1 to 0.92. Meanwhile, the sintering temperature decreased from 1250°C (x = 0.1) to 1150°C (x = 0.8 and x = 0.92), and both the dielectric constant and the τf value increased with the increase of the x value. Typically, the coexistence of the two phases resulted in a relatively porous structure that lowered the Q×f value of the ceramic system when the x value was 0.4 and 0.5. Sintered at the temperature of 1150°C, a Q×f value of 60,125 GHz with dielectric constant of 8.46 and τf value of −49.26 ppm/°C was obtained for the Ca(Mg0.92−xCoxAl0.08)(Si0.96Al0.04)2O6 ceramics with the x value of 0.92.