자동차용 초고장력강의 너트프로젝션 용접에서 용착강도 향상에 대한 연구

Abstract

Currently, an increasing number of products demand for the development of the automobile industry, we have made naturally increase the production rate accordingly. With the increase of these demands, resistance welding is used in the main welding method can be bonded in a relatively shorter time than other welding processes. Because of the environmental issues and improved fuel efficiency, weight reduction of the vehicle body is required. But data of the resistance welding process is not enough. In this study, it was conducting research in order to improve the welding strength in the weld nut projection welding of hot stamping boron steel. First, I elucidated the welding mechanism, and understand the process variables that affect the weld-ability. And I compared the Al-Si coating layer behavior and nugget growth in accordance with the steel grade of the weld nut, and selected one of the steels. Second, I analyzed the effect of the weld nut configuration, and secured the lobe curves for each conditions. Then, the spatters that affect weld quality was improved through the optimization process. As a result, I presented the proper welding conditions for the weld nut.