| 摘要 |
<p>PURPOSE:To reduce the voltage fluctuation of a varistor by heat-treating a sintered body in an oxidizing atmosphere after forming the sintered body by sticking a material composed mainly of aluminum to the surface of a molded body composed mainly of strontium titanate and baking the molded body in a reducing gas atmosphere. CONSTITUTION:A sintered body is formed by baking a molded body in a reducing gas atmosphere after molding the powder of a raw material composed mainly of strontium titanate in a desired shape and sticking a material composed mainly of aluminum to the surface of the molded body. Then the sintered body is heat-treated in an oxidizing atmosphere. Powder, paste, or a sheet composed mainly of aluminum is used as the material to be stuck to the surface of the molded body. Aluminum oxide can be used in place of the aluminum. Therefore, a varistor which is suppressed in voltage fluctuation and has a large nonlinear coefficient can be manufactured at a low cost, since the contrast between the high-resistance layer and semiconductor layer constituting the varistor becomes distinct.</p> |
