Effects of ZnO-H_3BO_3 addition on sintering behavior and dielectric properties of ZnO-MgO-TiO_2-CaO ceramics

摘要

Abstract ZnO-MgO-TiO2-CaO(abbreviated as ZMTC) dielectric ceramics were prepared by conventional mixed oxide route. The effects of ZnO-H3BO3(abbreviated as ZH) glass addition on the microstructures and dielectric properties of ZMTC ceramics were investigated. The formation of second phase can be detected at the high addition of ZH (8.0~16.0 wt%). Variation of grain shapes were observed with ZH content increasing. The sintering temperature of ZH-doped ZMTC ceramics can be effectively lowered from 1270 to 950 °C due to liquid phase sintering. The dielectric properties were affected by the amount of ZH addition. At 950 °C for 6 h, ZMTC ceramics with 8.0 wt% ZH possesses excellent dielectric properties: εr = 21.7, Qƒ = 60000 GHz, and TCF = 21.63 ppm/°C.