The influence of process variables on the microstructure and electrical properties of low-voltage ZnO varistor

摘要

The effects of process variables, such as sintering temperature, cooling rate, calcination, baling time on the microstructure and electrical properties of the low voltage ZnO varistor have been investigated. There exists a maximum sintering temperature when the breakdown field is the lowest. The results provide information about the grain size control to fabricate low voltage ZnO varistor, as well as the relationship between the microstructure and the varistor performance. We sicussed the sintering temperature dependence of breakdown field in terms of the formation rate of gain core and grain growth rate.