| 摘要 |
PURPOSE:To obtain an electrode material which excells in electric conductivity and hardness of the electrode, the refractoriness at the tip of the electrode, self-matchability, and the separability from a material to be welded by forming a copper alloy contg. a specific amt. of bismuth into a desired shape by casting or forging. CONSTITUTION:A copper alloy contg. 0.1-10wt% bismuth is formed by casting or forging into an electrode having a desird shape, and the bismuth in the copper alloy is diffusion precipitated like a cell at the grain boundary of copper or in the copper substrate, whereby an electrode material having high electric conductivity and hardness is obtd. The electrical heating to the electrode is repeated to form a refractory oxide at the tip thereof, and the oxide is stripped as fine powder from the tip, whereby the tip is separated from the material to be welded and the self-matching of the electrode tip is accomplished. The excellent electric conductivity and high heat transmission characteristic are thus provided to the electrode material in which large current flows and which receives strong pressing force. The realization of the electrode provided with satisfactory refractoriness and resistance to deformation at the tip thereof is made possible. |
