Simulation on the microvaristor chain formation in liquid epoxy under electric field

The composite varistor of epoxy resin and microvaristor has the nonlinear voltage-current characteristics owing to the microvaristor chains which work as current paths. These chains are formed by applying an electric field during curing process, and it is important to form the chains homogeneously so as to obtain the stable quality. Forming the chains is affected by various factors such as length between electrodes, size of microvaristors, applied electric field and gravity. Therefore, the authors established a simulation method of the microvaristor movement in a liquid under AC electric field. The simulation results on the chain formation agreed well with the experimental results.