| 摘要 |
<p>PURPOSE:To improve electrical characteristics by a method wherein a raw wire is heated to a temperature not lower than 700 deg.C and a part of the wire in a heating region is heated to a temperature not lower than the melting point to form a floating melt zone. CONSTITUTION:A case of, for instance, manufacturing an oxide resistor made of Bi-Sr-Cd-Cu2-Oy system material is described. First, the respective oxide powders of Bi2O3, SrO and, etc., are mixed and, after the mixture is formed into a wire, the wire is subjected to a thermal treatment to obtain a raw wire 1 having a composition of Bi-Sr-Cd-Cu2-Oy. The wire 1 is put into a heating furnace 5 and a current is applied to a heater 4a to heat the wire 1 to a temperature not lower than 700 deg.C. At that time, a current is applied to a resistance heating coil 4b to heat the top part of the wire 1 locally to form floating melt 3. Then the wire 1 is lifted and cooled in the air to be solidified and an oxide resistance wire 2 is obtained. Thus, by heating the raw wire and forming the floating melt zone stably, gaps can be stably eliminated. The development of crackings, therefore, can be avoided even if the wire 2 is subjected to heat-cycle and the electrical characteristics can be stabilized and free from the aging deterioration.</p> |
