With the advent of computational facilities, numerical simulation has become a powerful tool to estimate many interactions related to welding processes.

Researchers have employed finite element (FE) based numerical models to study residual stresses and distortion in fillet welds 1. In this investigation, a 3D thermal-mechanical FE procedure was adopted to predict thermal fields, angular distortion, and residual stresses in T-joint AA 6061-T6 plates welded using gas metal arc welding equipment.

The effect of welding sequences on the angular distortion and residual stresses of GMA welded AA 6061-T6 fillet joints were analysed using five different welding sequences. These sequences included welding in one direction (case 1), welding in the opposite direction (case 2), welding from the front end towards the centre and from centre to back end (case 3), welding towards the centre (case 4), and welding away from the centre (case 5).

Temperature-dependent material properties, heat loss due to conduction, radiation, and convection, and Goldak's volumetric heat source were employed in the model. The consumable filler material ER5356 grade alloy of diameter 1.2 mm was used in the experiments. For measuring angular distortions, data points were selected 25 mm apart at the top of the plate. To predict residual stresses in five different welding sequences, Von- Mises contours were compared.

From the obtained results it was found that in five different welding sequences, the minimum angular distortion was observed in case-5 i.e. the welding away from the centre. Also, the residual stress is found to be tensile near the weld region and compressive away from the weld region.

This article is shared by Tapas Bajpai and Sunil Pandey