溶胶—凝胶法制备CaCu_3Ti_4O_(12)-MgTiO_3复合陶瓷的介电性能与IV特性

Dielectric Properties and IV Characteristic of CaCu_3Ti_4O_(12)-MgTiO_3 Composite Ceramic Synthesized by Sol-Gel Method

通过溶胶凝胶方法制备得到CaCu3Ti4O12-MgTiO3复合陶瓷粉料,并在1000,1050和1100℃3个温度点烧结成瓷。采用XRD、SEM等对得到的样品成分、结构进行了分析,发现材料为CCTO-MgTiO3/MgTi2O4复相体系。在此基础上,对材料的介电性能、IV非线性特性做了相关测试。复合陶瓷在1100℃下烧结后,其介电常数比纯的CCTO要提高3到4倍。对材料的IV测试发现,复合陶瓷的IV非线性系数可以通过复合体系的线性法则拟合得到,材料的非线性系数约为4.56。

The CaCu3Ti4O12-MgTiO3 ceramics, containing main phases of CCTO and MgTiO3/MgTi2O4, were prepared by sol-gel method and then sintered at 1000, 1050 and 1100 ℃, respectively. The sample sintered at 1050 ℃ presents a high dielectric permittivity (~1×104) and a low dielectric loss (~0.1), both of which are stable with the temperature and frequency. The dielectric permittivity of the sample sintered at 1100 ℃ is about 3 times as that of pure CCTO samples sintered at the same temperature. The current-voltage nonlinear coefficient of the sample is 4.56.