Effect of Fe2O3 doping on the electrical and microstructural properties of ZnO-( Bi2O3, Sb2O3) varistor ceramics

This study will allow us to see the effect of Fe2O3 doping on the electrical and microstructural properties of the ceramic varistor based on (Bi2O3, Sb2O3). The study deals with a ZnO-based varistor, containing, 0.5 mol% of (Bi2O3, Sb2O3) doped with 1 mol%, 2 mol%, and 4 mol% of Fe2O3. The ceramics samples were developed using the conventional route of the oxides mixture, sintered all the samples at 1000 degree celsius. The mean grain size increased with the increase of the Fe2O3 amount and the grains were homogeneous, the varistors exhibited the relative density, the dielectric constant (epsilon '), dielectric dissipation factor (tan delta) and leakage current (IL) was increased with the increase of the Fe2O3 amount, Therefore, the nonlinearity coefficient (alpha) decreases from 23.58 to 8.61 and the breakdown field (Eb(1mA)) decreased from 341.41 to 202.01V/mm with an increase in the amount of Fe2O3.