| 摘要 |
PURPOSE:To obtain a W electrode material having superior ignition characteristic of an arc and consumption resistance by providing a composition containing Y2O3 in a prescribed percentage and having the balance consisting of W. CONSTITUTION:The W electrode material consists of 0.2-3.0wt% Y2O3 and the balance W. This W electrode material is manufactured, e.g., in the following way. At first, an aqueous solution of Y compounds is added to a metallic W powder (e.g. powder of 2-3mu average grain size) and the resulting mixture is blended and then heated to 300-500 deg.C in a hydrogen atmosphere so as to decompose the above-mentioned added compounds; as the Y compounds, nitrate compounds can be suitably used. Next, the resulting Y-added w powder is heated to 900-1,100 deg.C in a hydrogen air flow to undergo reduction, so that W powder in which Y2O3 is uniformly dispersed in the metallic W can be prepared. Subsequently, according to the conventional method in powder metallurgy, this W powder is subjected to press compacting, to sintering, and then to required workings such as swaging, etc., so that required W electrode material can be obtained. This W electrode material has ignition characteristic of an arc and consumption resistance equal to those of conventional thoriated tungsten.
|
