从材料组成、显微结构控制和制备工艺等方面综述了国内外高电位梯度ZnO压敏电阻片的研究进展,并展望了提高ZnO压敏电阻片电位梯度和通流容量的途径。采用三价过渡金属离子掺杂、减小添加剂粉料颗粒粒度以及控制合理的烧成制度,能明显减小晶粒尺寸,降低气孔率,增加晶界数目,提高晶界势垒,从而有效提高ZnO压敏电阻片的电位梯度。
The research and development of high potential gradient zinc oxide varistors including the chemical compositions, microstructure and processing are summarized in this paper. The possible methods to enhance the poten- tial gandient and energy absorption capability of zinc oxide varistors are suggested. Adding trivalent transition metal ions, reducing additives' particle size and controlling the sintering schedule can significantly reduce the grain size, low- er the porosity, increase the number of grain boundaries and enhance the grain boundary barrier, thus effectively improve the potential gradient of ZnO varistor.