Effects of ZBS glass addition on sintering behavior and properties of Ba6−3x(Sm1−yBiy)8+2xTi18O54(x = 2/3, y = 0.1) microwave dielectric ceramics

The ZnO-B2O3-SiO2(ZBS)-doped Ba6−3x(Sm1−yBiy)8+2xTi18O54 (x = 2/3, y = 0.1, BST) microwave dielectric ceramics were prepared via solid-state reaction route. The sintering behavior, microstructure and microwave dielectric properties of the ceramics were investigated systematically. The main crystalline phase of the ceramics was orthorhombic tungsten-bronze structure. But more than 3 wt% ZBS content leaded to secondary phase which were Bi0.56Sm1.44Ti2O7 and BaTi7O14. The results illustrated that large addition of ZBS would have an effect on the formation of the pure phase of BST(x = 2/3, y = 0.1) ceramics. The addition of ZBS as liquid phase sintering aid lowered the sintering temperature of BST ceramics successfully from 1250 to 1050 °C. However, excessive ZBS doping deteriorated the dielectric properties of ceramics dramatically. Considering the sintering temperature and microwave dielectric properties of the samples, the BST ceramics with 3 wt% ZBS doping content sintered at 1100 °C had the good dielectric properties: er = 68.4133, Q × f = 1879.89 GHz, τf = − 18.57 ppm/ °C.