Fabrication and electrical characteristics of flash-sintered SiO2-doped ZnO-Bi2O3-MnO2 varistors

• DOI: 10.1007/s40145-020-0404-7
• Publication Date: 2020-07-29T09:03:51Z
• Authors: Pai Peng; Yujun Deng; Jingpeng Niu; Liyi Shi; Yunzhu Mei; Sanming Du; Juan Liu; Dong Xu
• Keywords: Clay industries. Ceramics. Glass; 02 engineering and technology; 01 natural sciences; TP785-869; 0205 materials engineering; flash sintering; ZBMS varistors; electrical properties; 0103 physical sciences; SiO2 additive

AbstractThe dense ZnO-Bi2O3-MnO2-xSiO2 (ZBMS) varistors for x = 0, 1, 2, 3 wt% were fabricated by flash sintering method under the low temperature of 850 °C within 2 min. The sample temperature was estimated by a black body radiation model in the flash sintering process. The crystalline phase assemblage, density, microstructure, and electrical characteristics of the flash-sintered ZBMS varistors with different SiO2-doped content were investigated. According to the XRD analysis, many secondary phases were detected due to the SiO2 doping. Meanwhile, the average grain size decrease with increasing SiO2-doped content. The improved nonlinear characteristics were obtained in SiO2-doped samples, which can be attributed to the ion migration and oxygen absorption induced by the doped SiO2. The flash-sintered ZBMS varistor ceramics for x = 2 wt% exhibited excellent comprehensive electrical properties, with the nonlinear coefficient of 24.5, the threshold voltage and leakage current of 385 V·mm−1 and 11.8 µA, respectively.