| 摘要 |
PURPOSE:To provide an electrode for a spark plug having a large durability with which a sufficient weld strength can be obtained only by spot welding of an electrode base material with a precious metal chip by laser beam. CONSTITUTION:An electrode 10 for a spark plug comprises an electrode base material 1 in the form of a rod comprising heat-resistant and corrosion-resistant metal, and a precious metal chip 2 spot welded with an ignition part of the electrode base material 1 by laser beam. A spot welded part is formed as a closed ring alloy belt 30 which is formed continuous covering the whole circumference of a joint surface 20 of the electrode base material 1 with the precious metal chip 2 in which adjacent alloyed spots 3 are partly overlapped with each other. |
