Mitigation of residual stresses and distortions in thin aluminium alloy GMAW plates using different heat sink models

This study aims to minimise the residual stresses and distortions in thin butt-welded aluminium alloy 5052-H32 plates during gas metal arc welding process by using three different heat sink models employing thick backing plate and cooling fluids. Experiments are conducted to investigate the efficacy of these models on the temperatures, longitudinal and transverse residual stresses and distortions produced in the welded plates. The results are compared against numerical simulation results obtained using a commercial finite element analysis software ANSYS. Temperature-dependent thermal and mechanical properties of plates are used and coupled transient thermal-structural analysis based on thermo-elastic-plastic approach is conducted. Residual stresses are measured using X-ray diffraction and distortions using a coordinate measuring machine. Temperatures were measured using thermocouples. Results show good conformity between experimental and numerical results and that the heat sink model using a mixture of argon gas and water is the most suitable scheme to achieve the mitigation.