La2O3掺杂对Zn–Pr基压敏陶瓷电学特性的影响

Effects of La2O3 Doping on Electrical Properties of Zn–Pr Based Varistor Ceramics

利用固相烧结法制备出了ZnO–Pr6O11–Co2O3–Cr2O3–La2O3氧化锌压敏陶瓷。研究了La2O3掺杂对氧化锌压敏陶瓷微观结构、压敏特性以及介电性能等方面的影响。结果表明:在La2O3掺杂量为1.5%(摩尔分数)时,氧化锌压敏陶瓷的综合性能最好,其晶粒尺寸最小且较为均匀,击穿场强达到最高(752 V/mm),非线性系数较大(12),晶界电容达到最大(276 pF),介电损耗较小。

The ZnO–Pr6O11–Co2O3–Cr2O3–La2O3 varistors were prepared by solid state sintering method.The effect of La2O3 doping on the microstructure,varistor property,and dielectric characteristics of the ZnO varistor ceramics were studied in detail.The results show that the ZnO varistor has the best overall performance with La2O3 content of 1.5%(in mole fraction),the grain size is the smallest and uniform,the breakdown voltage E1 Ma is the highest(752 V/mm),the nonlinear coefficient is large(12),the grain boundary capacitance is the largest(276 p F),and the loss tangent is relatively low.