Abstract:
The influence of Bi2O3 and Sb2O3 doping on the microstructure and electrical characteristics of Zinc Oxide based varistor has been investigated. The as-sintered ceramic varistors with different compositions have been characterized via laboratory X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and electrical measurements. Bismuth oxide doping resulted in liquid phase sintering, rapid densification, grain growth and electrical varistor precipitating to a spinel phase and thereby inhibiting grain growth. Electrical property measurements indicate varistor behaviour for both cases of doping.