Microstructure, electrical and dielectric properties, and impulse clamping characteristics of ZnO-V2O5-Mn3O4 semiconducting ceramics modified with Er2O3

作者：Nahm Choon W^*

来源：Journal of Materials Science: Materials in Electronics , 2013, 24(10): 4129-4136.

DOI：10.1007/s10854-013-1371-3

This study focuses on the effect of Er2O3 on microstructure, electrical and dielectric properties, and impulse clamping characteristics of the ZnO-V2O5-Mn3O4 varistor ceramics. Analysis of the microstructure indicated that the ZnO-V2O5-Mn3O4-Er2O3 ceramics consisted of major ZnO grain and minor secondary phases such as Zn-3(VO4)(2), ZnV2O4, ErVO4, and VO2. As the amount of Er2O3 increased, the densities of sintered pellets increased from 5.46 to 5.52 g/cm(3), whereas the average grain size decreased from 7.2 to 6.0 mu m. The breakdown field increased from 1,016 to 3,185 V/cm with an increase in the amount of Er2O3. The highest nonlinear coefficient was obtained at the varistor modified with 0.1 mol%, reaching alpha = 30. The clamp voltage ratio (K), which indicates an impulse absorption capability, was improved with an increase in the amount of Er2O3 and the varistor modified with 0.25 mol% exhibited the best K = 2.41.

• 出版日期2013-10