The dense ZnO-Bi_(2)O_(3)-MnO_(2)(ZBMS)varistors for x=0,1,2,3 wt% were fabricated by flash sintering method under the low temperature of 850℃ within 2 min.The sample temperature was estimated by a black body radiati...The dense ZnO-Bi_(2)O_(3)-MnO_(2)(ZBMS)varistors for x=0,1,2,3 wt% were fabricated by flash sintering method under the low temperature of 850℃ 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 SiO_(2)-doped content were investigated.According to the XRD analysis,many secondary phases were detected due to the SiO_(2) doping.Meanwhile,the average grain size decrease with increasing SiO_(2)-doped content.The improved nonlinear characteristics were obtained in SiO_(2)-doped samples,which can be attributed to the ion migration and oxygen absorption induced by the doped SiO_(2).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 11.8μA,respectively.展开更多
基金financially supported by National Natural Science Foundation of China(Grant Nos.51802003 and 51572113)State Key Laboratory of New Ceramic and Fine Processing Tsinghua University(No.KF201808)the Project National United Engineering Laboratory for Advanced Bearing Tribology(No.201912).
文摘The dense ZnO-Bi_(2)O_(3)-MnO_(2)(ZBMS)varistors for x=0,1,2,3 wt% were fabricated by flash sintering method under the low temperature of 850℃ 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 SiO_(2)-doped content were investigated.According to the XRD analysis,many secondary phases were detected due to the SiO_(2) doping.Meanwhile,the average grain size decrease with increasing SiO_(2)-doped content.The improved nonlinear characteristics were obtained in SiO_(2)-doped samples,which can be attributed to the ion migration and oxygen absorption induced by the doped SiO_(2).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 11.8μA,respectively.