| 摘要 |
<p>PURPOSE:To obtain a zinc oxide varistor wherein voltage dependent nonlinerality is more improved, by specifying content of P in a varistor element. CONSTITUTION:Loadings of P is increased as compared with the conventional case, and the loadgings of P in a varistor element are set to be 0.25-0.5mol%. Additive is added to ZnO, and subjected to wet mixing in a pot mill. P is added in the form of H3PO3. After dehydration and drying, binder is added and granulation is performed by special apparatus. Molding is performed at a pressure of 1000kg/cm<2> and baking is performed at a temperature of 1200$0C for 2 hours, thereby obtaining a varistor element 1. Since the loadings of P to the varistor element is increased, solid solution amount of P in ZnO is increased. As the result, the resistivity of ZnO is remarkably decreased. Thereby voltage dependent nonlinearity in the high current region can be improved.</p> |
