Abstract
ZnO-based varistors were fabricated by sintering zinc oxide micro crystals with several additives of metal Oxides. The effect of sintering temperature on varistor properties of (131; Co, Cr, Mn, Sb, AI) -doped ZnO ceramics was investigated in the range of 1280-1350 degrees C. The average grain size increased to 513 to 7.88 pm with the increase of sintering temperature. However, the nonlinear coefficient of this system was nearly constant in the range of sintering temperature. The highest breakdown voltage was 1143.4 v / cm for the varistor sintered at 1350 degrees C the sample C sintered exhibited the best electrical properties.