Fabrication of Low-Voltage ZnO Varistors by a Two-Step Process

摘要

In order to make a low-voltage ZnO varistor of uniformly large-grained microstructure, a pure ZnO powder compact was first sintered at 1500℃. The abnormal grain growth that occurred during the sintering of the ZnO resulted in a relatively uniform matrix of very large grains. Subsequent heat-treatment in contact with a Bi_2O_3 powder mixture resulted in the formation of a low-voltage ZnO varistor.