Effects of Fe impurity on performances of ZnO varistors

被引：0

作者：

Lu Zhenya ^{[1
]}

Cai Yuanyuan

Chen Zhiwu

Wu Jianqing

机构：

[1] S China Univ Technol, Guangzhou 510640, Peoples R China

[2] S China Univ Technol, Dept Elect Mat & Engn, Guangzhou 510640, Peoples R China

来源：

RARE METAL MATERIALS AND ENGINEERING | 2007年 / 36卷

关键词：

ZnO varistors; Fe impurity; electric performances;

D O I：

暂无

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The effects of Fe impurity on the performances of ZnO-based ceramic varistors are investigated. With the Fe content increases, the surge residual voltage increases and the pulse impulsion resistance decreases seriously. XRD analysis reveals that solid solution Zn7Sb2O12- ZnFe2O4 forms in the grain boundaries. And some added Fe ions enter the ZnO grains which cause the decrease of the crystal lattice parameters. When the trivalent Fe cation substitute for Zn cation, half number vacancies form in the Zn sublattice. During the temperature decreasing process, the trivalent Fe ions in the Zn sublattice combine with conductive electrons contributed by donor additives or interstitial Zn ions. As a result, the resistance of ZnO grains increases, the non-linear coefficient in high current area is depressed and the residual voltage increases.

引用

页码：187 / 190

页数：4