采用传统固相法制备了ZnNb_2O_6微波介质陶瓷。研究了预烧温度对ZnNb_2O_6陶瓷的相结构、显微结构以及微波介电性能的影响。研究结果表明:预烧温度的变化对ZnNb_2O_6陶瓷的物相组成基本没有影响;随着陶瓷粉料预烧温度的上升,ZnNb_2O_6陶瓷的介电常数εr和品质因数Qf均呈现先增后降的变化规律,而陶瓷的谐振频率温度系数τf则向负值增大的方向变化;经950℃预烧处理的ZnNb_2O_6陶瓷粉体在1170℃烧结4 h可获得较佳的微波介电性能:ε_r=24.15,Q×f=69160 GHz,τf=-78×10^-6/℃。
ZnNb_2O_6 microwave dielectric ceramics were prepared by the traditional solid-state method. The effects of pre-sintering temperature on the phase structure, microstructure and microwave dielectric properties of the ceramics were investigated. The results indicated that the change of the pre-sintering temperature had no effect on the phase composition of ZnNb_2O_6 ceramics. With the increase of pre-sintering temperature of ceramic powders, the dielectric constant(εr) and the quality factor(Q×f) of ZnNb_2O_6 ceramics increased first and then decreased. However, the negative value of the temperature coefficient of the resonant frequency τf showed increase trend. The optimal microwave dielectric properties of ε_r=24.15, Qf=69160 GHz,τf=-78×10^-6/ ℃ were obtained for ZnNb_2O_6 ceramics sintered at 1170 ℃ for 4 h by pre-sintered at 950 ℃