Effect of B2O3 Additives on the Sintering and Dielectric Behaviors of CaMgSi2O6 Ceramics

The effects of B2O3 addition, as a sintering agent, on the sintering behavior, microstructure and dielectric properties of CaMgSi2O6 ceramic have been investigated. The CaO-MgO-B2O3-SiO2 glassy phase came forth by adding B2O3 into CaO-MgO-SiO2 ceramic powders, and it was advantageous to lower the synthesis temperature of CaMgSi2O6 crystalline phase. Moreover, the emergence of CaO-MgO-B2O3-SiO2 glass phase could effectively lower the sintering temperature of CaMgSi2O6 ceramic and promote the CaMgSi2O6 grains growing. With 6 wt pct B2O3 addition, the densification temperature of CaMgSi2O6 ceramic could be effectively reduced from 1300 to 1100°C, and the dielectric constant (ɛr) and dielectric loss (tanδ) were: ɛr=7.61 and tanδ=7.4×10−4 (1 MHz).