스테인리스강의 Heat Sink Welding시 용접변형 저감 특성에 관한 연구

Abstract

The HSW(Heat sink welding) process is a technology that reduces welding deformation and residual stress of the weld by spraying a heat sink medium along the welding arc at the same time as welding processes. Furthermore, it is effective in reducing longitudinal deformation and angular deformation of thin plate structures with low stiffness and it is possible to control deformation in real time, thereby shortening the post-processing time for welding deformation. In this study, 3-D thermal elastic plastic analysis was performed using HSW on 3mm thick 304L stainless steel, and welding deformation reduction characteristics were investigated according to heat sink process parameters such as the distance from the welding heat source to the center of heat sink area, and the effective heat sink radius. From the result, numerical simulation model shows that the cooling efficiency is significantly increase as the standoff distance is shorter and the heat sink radius is smaller. Moreover, it was confirmed that the longitudinal deformation and angular deformation were 2.22mm and 0.51mm under the heat sink condition of a standoff distance of 40mm and a heat sink radius of 7.5mm, which was about 60% and 70% less than the conventional welding.