Effects of ZnO–B2O3 addition on sintering behaviors and microwave dielectric properties of Ba4Sm9.33Ti18O54 ceramics

Abstract

Effects of ZnO–B₂O₃ (ZB) addition on the densification, phase evolution and microwaves dielectric properties of Ba₄Sm_9.33Ti₁₈O₅₄ (BST) ceramics for low-temperature fired applications have been investigated. The sintering temperature of BST ceramics can be effectively lowered to about 1000°C with introduction of ZB. Tungsten bronze like single phase is observed in the BST ceramics with 0.5 and 1.0% ZB. However, Sm₂Ti₂O₇ secondary phase appears when ZB addition reaches 2%, and Sm₂Ti₂O₇ phase gradually increases with the increase ZB addition. Microwave dielectric properties of the present ceramics are strongly dependent on phase constitution and density. Optimal microwave dielectric properties of ε = 63.4, Qf = 2830 GHz, τ_f =–8.8 ppm/°C is obtained for BST ceramics with 1% ZB addition.