Numerical Investigation on Reduction Characteristics of Welding Deformation According to Standoff Distance in Heat Sink Welding Process

Abstract

Welding with a trailing heat sink process is proposed as a useful technique to reduce welding deformation without a significant loss of manufacturing efficiency. In particular, this method is effective than the existing mechanical or thermal correction method in thin plate steel structures with low stiffness. In this study, a three-dimensional thermal elastic-plastic finite element model using a 3-mm thick 304L stainless steel sheet was developed to simulate heat sink welding. The reduction characteristics of welding deformation according to the standoff distance between the welding heat source and the heat sink zone was investigated in the numerical simulation. The results confirmed that the longitudinal and angular deformations were significantly reduced compared with those by conventional welding. The longitudinal deformation was reduced by approximately 60%, from 5.50 mm to 2.22 mm, and the angular deformation was reduced by approximately 70%, from 1.68 mm to 0.51 mm. The overall results obtained in the numerical analysis indicated that welding deformation significantly decreased as the standoff distance was shorter owing to the temperature cooling effect of the welds.