Effect of B2O3 additive on the sintering temperature and microwave dielectric properties of Ba(Mg1/3Ta2/3)O3 ceramics

This paper reported a research of the sinterability, microstructures, and microwave dielectric properties of Ba(Mg1/3Ta2/3)O3 (BMT) ceramics with different amounts of B2O3 additive. The results showed that B2O3 addition had an obvious effect on reducing the densification sintering temperature without detriment of the dielectric properties. Appropriate B2O3 addition could effectively lower the densification sintering temperature of BMT ceramics from 1650 to 1250 °C and achieved superior microwave dielectric properties. However, surplus B2O3 content addition caused abnormal grain growth and therefore deteriorated the densification and microwave dielectric properties of the BMT ceramics. Finally, BMT ceramics with 3 wt% B2O3 possessed superior microwave dielectric properties: εr = 24.2, Q × f = 92,600 GHz (f = 8 GHz), and τf = 3.5 ppm/°C were achieved when sintered at 1250 °C.