物理学报2012，Vol.61Issue(15)：147-152,6.
ZnO压敏陶瓷缺陷结构表征及冲击老化机理研究
Characterization of defects and research on impulse aging in ZnO varistor ceramics
摘要
Abstract
The electrical and dielectric properties and the microstructures of a polynary ZnO-based varistor ceramics with 14000 times impulse current aging test are measured.The relationship between defect structure and impulse current aging is mainly investigated. It is found that the electrical properties decrease rapidly with impulse aging and the dimensional effect of ZnO varistor ceramics is dominated not only by grain but also by grain boundary.Additionally,four defect relaxations are found at different temperatures by using dielectric spectra.Two defect relaxations appearing below—60℃with activation energies about 0.24 eV and 0.35 eV are identified to be intrinsic defects originating from interstitial Zn L（Zn_i） and vacancy oxygen L（V_o）,which are not affected by impulse current aging.Other two relaxations appearing above 80℃are suggested to be extrinsic defects originating from trap levels L（ingr） at intergranular phase and trap levels L（gb） at grain-boundary interfaces,respectively.Only L（gb） decreases from 0.84 eV to 0.76 eV due to impulse current aging while other trap levels keep unchanged.It is further proposed that L（gb） is responsible mainly for the electrical property and stability of ZnO ceramics.关键词
ZnO压敏陶瓷/缺陷结构/冲击老化/压敏电压Key words
ZnO varistor ceramics/defect structures/impulse degradation/varistor voltage分类
化学化工引用本文复制引用
赵学童,李建英,李欢,李盛涛..ZnO压敏陶瓷缺陷结构表征及冲击老化机理研究[J].物理学报,2012,61(15):147-152,6.基金项目
国家自然科学基金（批准号：50977071,51177121）资助的课题 （）
