The effects of B2O3 additives on the microstructures and the microwave dielectric properties of complex perovskite 0.66Ca(Mg1/3Nb2/3)O3-0.34CaTiO3 ceramics were investigated. The B2O3 additives, acting as a sintering aid, can effectively lower the sintering temperature of the ceramics to as low as 1200 °C. No second phase was observed throughout the entire experiments. Moreover, boron was not found in the grains but residual at the boundaries indicating a liquid phase sintering. At 1250 °C, the 0.25 wt% B2O3-doped 0.66Ca(Mg1/3Nb2/3)O3-0.34CaTiO3 ceramics possesses a relative permittivity εr of 43.94, a Q × f value of 30,000 GHz (measured at 6.7 GHz) and a τf value of -1.9 ppm/°C. It exhibits a substantial temperature reduction (>200 °C) and compatible dielectric properties in comparison with that of un-doped one.
All Science Journal Classification (ASJC) codes
- Mechanics of Materials
- Mechanical Engineering
- Metals and Alloys
- Materials Chemistry