BSTO/MT复合陶瓷的结构及介电性能

Structure and Dielectric Properties of BSTO/MT Composite Ceramic

用固相反应法制备了Ba0.45Sr0.55TiO3-Mg2TiO4复合陶瓷，研究了陶瓷的烧结特性、相组成、显微组织及介电性能。结果表明，复合陶瓷可在1325～1430℃范围烧结成瓷，X-射线衍射仪（xRD）、EDS和SEM分析表明复合陶瓷由Ba0.45Sr0.55TiO2和Mg2TiO4两相组成，没有杂相出现，但两相间存在元素扩散现象。在Mg2TiO4质量分数为70％，10kHz、25℃时，试样的介电常数为98．2，介电损耗为0．0007，介电可调度Tun达12．2％（电场2kV／mm），在-20-50℃温度范围内，该组分的优化因子K值均大于80。

Ba0.45Sr0.55TiO3-Mg2TiO4 composite ceramic was fabricated by solid-state reaction technique. The sintering behavior, phase distribution, micrograph structure and dielectric properties were investigated. The results showed that the dense ceramic could be obtained between 1 325-1 430℃. XRD,SEM and EDS analysis detected that the main phase of the ceramic wereBa0.45Sr0.55TiO3 and Mg2TiO4 phases, without any other phase, but the inter-diffusion occured between two components. As the content of Mgz TiO4 was 70M, an optimum ceramic composite was attained with dielectric constant 98.2, loss tangent 0. 000 7, dielectric tunability 12.2 % （under a dc electric field 2 kV/mm） at 10 kHz,25℃, and within the temperature range from --20 ℃ to 50℃, the K-factor was above 80.