Reduction Characteristics of Welding Deformation According to Cooling Distance in Heat Sink Welding

Abstract

When assembling a welding structure, welding deformation occurs inevitably due to the locally applied heat source. This not only decreases the strength of the structure but also decreases productivity efficiency. In recent years, in-process control welding by an additional cooling source has been applied for thin-plate structures. In the present study, a numerical analysis of Heat Sink Welding (HSW) was performed to examine the effect of the heat sink source on the degree of welding deformation. Then the numerical result was compared with that of conventional welding. Moreover, the result predicted from the numerical analysis was compared with the experimental result on displacement to be validated. As a result, a cooling zone appeared on the welding metal surface. In the case of the heat-affected zone (HAZ), it was confirmed that the maximum temperature decreased from 596 to 545 K compared to the conventional welding method. In addition, the displacement in the thickness direction decreased by about 5%, from 0.83 to 0.79 mm. The overall results obtained in numerical analysis indicated that the cooling efficiency significantly increases as the cooling distance is shorter.