摘要 |
In order to extend a lifetime of a welding tip in a simple way, a surface reinforcing layer 2 is formed by ejecting a metal powder shot onto at least an inner peripheral surface of a welding tip 1 (1, 12) formed of any material of copper, a copper alloy or ceramic-dispersed copper at an ejection velocity of 100 m/sec or higher. The metal powder shot has an average particle diameter of 40 to 150 mum and hardness equal to or higher than the material of the welding tip 1 (11, 12). Then, a semiconductor film 3 is formed on the surface reinforcing layer 2 by further ejecting a tin powder with an average particle diameter of 10 mum to 100 mum having a tin oxide film formed thereon onto the surface reinforcing layer 2 at an ejection velocity of 200 m/sec or higher. |