Effect of the B2O3 addition on the sintering behavior and microwave dielectric properties of Ba3(VO4)2–Zn1.87SiO3.87 composite ceramics

Abstract The effect of the B 2 O 3 addition on the low-temperature sintering, microstructure and microwave dielectric properties of the Ba 3 (VO 4 ) 2 –Zn 1.87 SiO 3.87 composite ceramics was investigated. The results indicate that the addition of B 2 O 3 can effectively promote the densification and further improve the microwave dielectric properties of the composite. The low-temperature sintering mechanism was ascribed to the formation of the liquid phase owing to the reaction between the additive B 2 O 3 and the residual SiO 2 in the composite. B 2 O 3 –SiO 2 liquid phases can not only lower the sintering temperature, but also speed up the grain growth of the composite ceramics. The rapid grain growth occurs as the B 2 O 3 content is more than 6 wt%. The 3 wt% B 2 O 3 doped 0.5Ba 3 (VO 4 ) 2 –0.5Zn 1.87 SiO 3.87 ceramics can be well sintered at 925 °C and exhibit excellent microwave dielectric properties of Q × f ∼40,800 GHz, e r ∼10 and τ f ∼0.5 ppm/°C.