First-grade protective high-energy varistor and preparation method thereof

The invention discloses a first-grade protective high-energy varistor and a preparation method thereof. The varistor is composed of 90.7-97.7 mol% of zinc oxide and the remaining amount of an additive, wherein the additive is composed of Co element, Mn element, Ni element, Cr element, Sb element and Bi element, and the molar percentages of the added elements in terms of oxide forms are as follows:0.5-1.5 mol% of Co3O4, 0.2-1.2 mol% of Mn2O3, 0.2-1.2 mol% of NiO, 0.2-1.2 mol% of Cr2O3, 0.7-1.7 mol% of Sb2O3, and 0.5-2.5 mol% of Bi2O3. According to the varistor prepared by adopting the formulaand process conditions provided by the invention, the 34S product of the varistor can withstand single impact of 8 KA or more under the waveform of 10/350, the use performance is greatly improved, andthe varistor can fully meet requirements for use. 本发明公开一种一级防护高能性压敏电阻及其制备方法，压敏电阻由氧化锌及添加剂组成，其中ZnO含量为90.7～97.7mol%，其余量为添加剂；所述的添加剂由Co、Mn、Ni、Cr、Sb和Bi元素组成，添加的各元素按其氧化物形式计算的摩尔百分数分别如下：CoO为0.5～1.5，MnO3为0.2～1.2，NiO为0.2～1.2，CrO为0.2～1.2，Sb