Effect of dual heat sink treatment during welding on distortion and mechanical properties

Welding results must be distorted as little as possible, because distortion can reduce weld dimensions accuracy, lengthen the repair process, and raise production costs. The purpose of this research is to investigate the effects of the dual heat method on distortion and mechanical properties. The heat sink uses hollow stainless steel rods filled with running water at a temperature of ±27°C which is applied simultaneously with the welding process. The single heat sink is characterized by the heat sink being above the workpiece, while the dual heat sink is characterized by the heat sink above and below the workpiece. The results showed that the treatment of single heat sink and dual heat sink reduced the distortion level significantly by 58% and 66%, respectively. Tensile test results show a tendency for the same value between as welded, single heat sink and dual heat sink, which is around 480 N/mm2 (480 Mpa), meaning that the heat sink does not reduce the tensile strength of the weld metal and HAZ. The results of the as-welded and dual heat sink bending tests also showed that the bending test passed the AWS criteria. Impact test results show a decrease in the toughness of the weld metal due to heat sink treatment.