表面层对TiO_2压敏陶瓷电学性能的影响  

Effect of Surface Layer on the Electrical Properties of TiO_2 Based Varistors

作　　者：张小文[1] 甘国友[1] 严继康[1] 陈敬超[1] 杜景红[1] 

机构地区：[1]昆明理工大学材料与冶金工程学院

出　　处：《压电与声光》2005年第3期260-262,共3页Piezoelectrics & Acoustooptics

基　　金：云南省科技攻关基金资助项目(2002GG09)

摘　　要：用电子陶瓷工艺制备了(La,Sr)掺杂的TiO2压敏-电容双功能元件,其压敏电压(V1mA)为8～38V·mm-1,非线性系数为3～5.5,介电常数可达105。样品的压敏电压受表面层影响显著,随着厚度的减少,V1mA从27～38V·mm-1降至8～15V·mm-1,但非线性系数与介电常数受表面层的影响甚小,这主要与烧结后在冷却过程中,空气中的氧在样品表面沿晶界扩散所形成的表面"氧化层"有关。The preparation and properties of (La,Sr)-doped TiO_2 varistors are systematically investigated.Samples have sensitive voltage (V_(1 mA)) of 8～38 V·mm^(-1), nonlinear coefficient of 3～5.5 and dielectric constant of 10~5.The sensitive voltage is greatly reduced from 27～38 V·mm^(-1)to 8～15 V·mm^(-1)with the reduction of thickness, however, nonlinear coefficient and dielectric constant are not affected by surface layer, which is mainly relevant to the 'oxidized surface layer' caused by diffusion of oxygen at the surface during cooling.

关 键 词：二氧化钛 压敏电阻 双功能 表面效应 陶瓷 

分 类 号：TN379[电子电信—物理电子学]