基于传统电子陶瓷合成工艺,采用二次合成法在950℃合成了组织均匀、瓷体相对密度〉98%、非线性系数〉50的ZnVSb基多组分压敏电阻陶瓷材料。Sb以V2O5/Sb2O3预合成粉的形式进行添加,避免了由于Sb2O3挥发造成的对ZnO晶粒生长的阻碍,促进了陶瓷的低温烧结。随着预合成粉含量的增加,Sb^3+离子对Zn^2+离子的取代量增加,材料内部矿二等受主型缺陷的增加,使晶界势垒升高,使材料获得优异电学非线性特性。
Antimony doped ZnO-V2O5 varistor ceramics were synthesized at 950℃ by traditional electronic ceramic fabricating method with a modification in pre-calcining Sb2O3 with V2O5. By this two step fabrication, the hindering effect of Sb2O3 on the grain growth of ZnO grains, caused by its volatilization and re-coagulation on the surface of growing zinc oxide grains during the sintering process, could be avoided, by which the low temperature sintering of the ceramic is greatly promoted. As the content of presynthesized V2O5/Sb2O3 compound increases, VZn^* typed acceptors increase due to the way to add Sb into the ceramics in form of V2O5/Sb2O3. resulting in more substitutions of Sb^3+ cation for Zn^2+ cation. This finally contributes to the higher grain boundary barrier height and the better current-voltage nonlinearity of the ceramics. The optimum properties of the ceramic, with relative density 〉98%, nonlinearity exponent a〉50, could be achieved, the ceramic's potential in producing multilayer varistor is reasonably promoted.