铌掺杂对Ce-Nb-TiO_2系压敏陶瓷结构与电性能的影响  

Effect of Nb on Microstructure and Electric Properties of Nb and Ce doped TiO_2 Based Varistor Ceramics

作　　者：姬颖敏[1] 唐子龙[1] 苏利红 李红耘[1] 罗绍华[1] 

机构地区：[1]新型陶瓷与精细工艺国家重点实验室清华大学材料科学与工程系,北京100084 [2]河南省滑县滞洪管理局,滑县456465

出　　处：《电瓷避雷器》2006年第5期21-24,28,共5页Insulators and Surge Arresters

基　　金：清华大学新型陶瓷与精细工艺国家重点实验室开放课题基金(X.GZ0207).

摘　　要：研究了铌对Ce,Nb掺杂的二氧化钛压敏陶瓷结构和电性能的影响。结果表明,在1 350℃烧结条件下,掺入0.8%Nb2O5的样品具有优良的综合电性能,显示出低的压敏电压(U1mA=7.22V/mm)、高的非线性系数(α=5.76),是一种很有潜力的新型电容-压敏陶瓷材料。铌掺杂主要是Nb5+对Ti4+的掺杂取代,该掺杂存在一饱和值。Nb2O5在不同的掺杂浓度下,存在的形式和位置不同,同时与一些低熔点化合物相如Ce2Ti2(Si2O7)O4等相互作用,使得样品的电性能发生变化。The microstructure and electrical properties of （Ce, Nb）-doped TiO2 ceramics with various Nb2O5 amount had been investigated by varistor and dielectric measurements, SEM, EDAX and XRD. It was found that the Nb2O5 dopant had significant effect on the varistor properties and dielectric properties of （Ce, Nb）-doped TiO2 based varistor ceramics sintering at 1 350℃. An optimal composition dopant with 0.8% Nb2O5 was obtained with low breakdown voltage of 7.22 V/mm, high nonlinear coefficient of 5.76. It is a potential new type material for capacitor and varistor. The Nbdopping is attributed to substitution of Nb^5＋ to Ti^4＋ . As the content of Nb2O5 increases, its form and position of existence are different. The characteristics of the ceramics can be explained by the effect and the maximum of the substitution of Ti^4＋ with Nb^5＋ , and the interaction between Nb^5＋ and some lowmelting compounds such as perrierite （Ce2Ti1（Si2O7）O4） produced on grain boundary and sample face.

关 键 词：Ce—Nb—TiO2系压敏电阻 压敏陶瓷微观结构 压敏电阻电性能 

分 类 号：TM282[一般工业技术—材料科学与工程]