새로운 저항용접 공법에 의한 자동차강판 접합기술

RSW(Resistance Spot Welding) have been the most successful sheet metal joining process in automotive industry for many decades. However, there are certain limitations due to the access of welding gun and electrodes. Laser welding or arc welding is used to weld a closed section and hydro-formed parts where resistance spot welding is hard to apply. In this research, an automated single-sided spot welding system is introduced to overcome typical RSW issues and its applications to automotive body assembly are presented. This new welding machine is designed to make a weld by singled-sided access with low electrode force. Weldability lobe curves were developed to find applicable operating conditions and found that relatively low welding current was possible to make a reasonable size of weld nugget. Various applications for Body-In-White were investigated. Hydro-formed side member parts and brackets were welded together and got successful result. Large floor panels were joined together with small-sized single-sided welding gun. Although a few limitations and challenges have to be considered to maintain good-quality weld, this technique can be a great alternative to hard-to-spotweld applications on automotive body assembly.