Low-temperature-sintering characteristic and microwave dielectric properties of (Zn0.7Mg0.3)TiO3 ceramics with LBSCA glass

Abstract

(Zn0.7Mg0.3)TiO3 (ZMT) powders were synthesized by a traditional solid-state preparation process. Meanwhile, the effects of adding Li2O–B2O3–SiO2–CaO–Al2O3 (LBSCA) glass on the microstructure, phase formation, and microwave dielectric properties of ZMT ceramic were investigated. The LBSCA glass as a sintering agent can effectively reduce the sintering temperature of ZMT ceramic from 1100°C to 900°C, which can be attributed to its liquid-phase effect. Only 0.5wt% LBSCA-doping contributed to a 20.2% increase in relative density. XRD patterns indicated that ZnTiO3 was the major crystalline phase. Scanning electron microscopy images demonstrated that low LBSCA-doping (≤2.5wt%) promoted the grain densification and uniformity of specimens. A dense microstructure with uniform grain size could be obtained with 1wt% LBSCA and sintered at 900°C. The ceramic also exhibited excellent microwave dielectric properties: εr=21.6; Q×f=62,000GHz; and τf=−60ppm/°C.