| 摘要 |
PURPOSE:To obtain a zinc oxide type varistor with a large surge resisting amount of sintering a mixture whose main component is zinc oxide, and sub- compoents are bismuth oxide, chromium oxide, etc., and further containing a predetermined amount of boron silicide. CONSTITUTION:Raw material powder is formed whose main component is zinc oxide, and sub-components are bismuth oxide, chromium oxide, etc., and further to which at least 0.05-0.5mol% boron silicide, when converted to the form of SiB6, is added. Next, this raw is compression molded, then sintered, and further glass paste 3 is applied to the side surface of the sintered body 1 and baking treatment is carried out. Both end surfaces of thus obtained sintered body are polished to form flame sprayed electrodes of 2 of Al. Namely, boron silicide suppresses the growth of zinc oxide grains as conventional silicon oxide, and moreover the bulk specific gravity thereof is high and grinding proceeds uniformly, and has good dispersibility so that voids are scarcely produced. Thus, a zinc oxide type varistor with a large surge resisting amount can be obtained. |
