| 摘要 |
PURPOSE:To improve a damp-proof property and to provide a surgeproof property without deterioration of a voltage-current property by adding B2O3, CdO and PdO to ZnO or ZnO and MgO. CONSTITUTION:A damp-proof property is improved by adding 0.02 to 2.0 mol% of B2O3 to a metal oxide which is composed of ZnO or ZnO and MgO as a major component. A varister voltage is elevated and a current-voltage property and damp- proof property are improved by adding 0.1 to 3.5 mol% of CdO. But addition of only CdO results a deterioration on standing and an insufficient damp-proof property. The damp-proof propery and current-voltage property are further improved by adding 0.2 to 2.0 mol% of PbO besides B2O3 and CdO. The varister voltage is lowered, the non-linearity and damp-proof property are not improved with only PbO. With B2O3 and PbO, PbO is not effective. |
