스텐레스 철도차량 외판 압흔 깊이 감소를 위한 스폿용접용 전극팁 개발

Development of electrode tips for spot welding to reduce indentation of car body surface of stainless rolling stocks

Stainless rolling stocks are usually fabricated by spot welding process without painting. Indentation on the surface of the car body after spot welding injures the beauty of the stainless rolling stocks. In this study, electrode tips to reduce the indentation are developed and applied to the actual spot welding works. The developed tips are composed of head, nut hole far cooling water, body and resistance material. They provide large surface contact area with the base materials during spot welding and enhance the current density by necking. Experimental results using the developed tips show that small indentation and sufficient tensile shear strength is produced due to large contact area and enhanced current density.