Comparative Evaluation of Oscillating Fiber Laser Welding and GMAW/MAG for SAE 1010 Agricultural Wheel Rims

This study evaluates oscillating fiber laser welding as an alternative to gas metal arc welding with an active shielding gas (GMAW/MAG) for manufacturing 4.25 mm thick SAE 1010 agricultural wheel rims. A systematic product development approach guided technology selection. The comparison included process energy, weld geometry, microstructure, grain size, Vickers microhardness, guided-bend testing, and industrial forming. Estimated GMAW/MAG heat input was 0.64 kJ/mm, whereas nominal incident laser energy was 0.019 kJ/mm; these quantities do not represent equivalent measurements of absorbed heat. Measurements from one transverse cross-section per welding condition showed a smaller weld-face width (5.70 vs. 12.97 mm), lower convexity (0.56 versus 3.93 mm), and a narrower heat-affected zone (0.85 versus 2.10 mm) for laser welding compared with GMAW/MAG. Less grain coarsening was observed in the laser-welded heat-affected zone. Mean fusion-zone hardness was 158.6 ± 18.9 HV1 for laser welding and 190.4 ± 11.0 HV1 for GMAW/MAG. Both conditions passed the guided-bend tests. All ten laser-welded specimens completed industrial forming, whereas two of ten GMAW/MAG specimens fractured during cone opening. The examined laser-welded cross-section exhibited a narrower weld profile than the examined GMAW/MAG cross-section. The laser-welding manufacturing route also eliminated the post-weld grinding operation under the investigated conditions.