Microwave Dielectric Properties and Thermally Stimulated Depolarization Currents of (1-x)MgTiO3-xCa(0.8)Sr(0.2)TiO(3) Ceramics
Microwave Dielectric Properties and Thermally Stimulated Depolarization Currents of (1-x)MgTiO3-xCa(0.8)Sr(0.2)TiO(3) Ceramics
复制标题
(1-x)MgTiO3-xCa(0.8)Sr(0.2)TiO(3)陶瓷的微波介电性能和热激去极化电流
DOI：
10.1111/jace.13485
复制
发表时间：
2015
影响因子：
3.9
通讯作者：
Li Longtu
中科院分区：
文献类型：
--
作者：
Zhang Jie;Yue Zhenxing;Zhou Yuanyuan;Zhang Xiaohua;Li Longtu
采用常规固相反应法制备了（1−x） MgTiO3-xCa0.8Sr0.2TiO3（0.04≤x≤0.2,MT‐CST）复合陶瓷。研究了其相组成、微波介电性能和微波介电损耗机理。采用ca0.8 sr0.2 tio3作为MgTiO3的τ补偿器，两者共存良好，不形成二次相。有趣的是，通过介电温度谱，在所有MT - CST陶瓷中都观察到与氧空位缺陷相关的显著介电弛豫。因此，热模拟退极化电流得到了与外在介质损耗机制相关的缺陷。缺陷偶极子和晶粒内氧空位的浓度随x的增加而增加，从而引起微波介电损耗。结果表明：ofQ×fwere的行为主要受相组成和缺陷的影响。温度稳定的陶瓷在x= 0.06时，其微波介电性能分别为εr= 21.19,Q×f= 110 900 GHz (f= 9.295 GHz), τf=−0.9 ppm/°C。
(1 −x)MgTiO3–xCa0.8Sr0.2TiO3(0.04 ≤x≤ 0.2, MT‐CST) composite ceramics were prepared by the conventional solid‐state reaction process. The phase composition, microwave dielectric properties, and microwave dielectric loss mechanisms were studied. Ca0.8Sr0.2TiO3was employed as a τfcompensator for MgTiO3, and they coexisted well without forming any secondary phases. Interestingly, significant dielectric relaxations associated with oxygen vacancy defects were observed in all the MT‐CST ceramics through the dielectric‐temperature spectra. Thermally simulated depolarization current was therefore conducted to obtain the defects associated with extrinsic dielectric loss mechanisms. The concentrations of both defect dipole and in‐grain oxygen vacancies increased with the increasingx, which could induce microwave dielectric loss consequently. It demonstrated that the behaviors ofQ×fwere basically influenced by phase composition and defects here. Temperature‐stable ceramics can be achieved atx= 0.06, where the microwave dielectric properties were εr= 21.19,Q×f= 110 900 GHz (f= 9.295 GHz), and τf= −0.9 ppm/°C, respectively.