中温热补偿MLC陶瓷

Temperature Compensating MLC Ceramic Sintered at Intermediate Temperature

本文研究了ＢａＯ－ＴｉＯ＿２－Ｎｄ＿２Ｏ＿３（ＢＴＮ）系陶瓷的结构和介电性质。在该系统中加入适量的玻璃和添加剂，获得了一系列中温热补偿独石电容器（ＭＬＣ）陶瓷，实验结果证实：当Ｔｉ／Ｂａ＝１．００３时，ＢＴＮ系陶瓷的居里温度（Ｔ＿ｃ）随Ｎｄ＿２Ｏ＿３含量的增大而产生逐步漂移。用ＸＲＤ确定了陶瓷的主晶相，ＳＥＭ照片显示出晶粒尺寸对Ｎｄ￣（３＋）含量的依赖关系，分析了Ｔｉ／Ｂａ比对陶瓷介电系数温度系数（α＿ε）的影响。通过改变Ｎｄ＿２Ｏ＿３含量和Ｔｉ／Ｂａ比可调节ＢＴＮ系的介电常数（ε）和α＿ε。此外，也讨论了ＣａＴｉＯ＿３对ＢＴＮ系电性能的影响。

The structure and dielectric properties of BaO-TiO_2-Nd_2O_3,(BTN) ceramics are studied. Doping with appropriate amount of glass and additives in the system,a series of temperature compensating monolithic capacitor ceramic (MLC) is obtained at intermediate firing temperature. The experimental results prove that the Curie temperature (T_c) of BTN ceramics shows a gradual shift with the increasing of Nd_2O_3 when Ti/Ba=1.003. The micrographs taken by SEM show that the grain size depends on Nd￣(3+) content. The influence of Ti/Ba ratio on the temperature coefficient of permittivity (α_ε) of the ceramic has been investigated. The permittivity (α_ε) and(ε) of BTN system can be adjusted both by changing the Nd_2O_3 content and Ti/Ba ratio. Moreover,the influences of CaTiO_3 on the electrical properties of BTN are also analyzed.