Enhancing weld joint performance of dissimilar aluminium alloy joints through filler rod selection

In this work, Tungsten Inert Gas (TIG) welding with four distinct filler rods—ER4043, ER4047, ER5183, and ER5356—is used to explore the mechanical properties and microstructural features of butt-welded joints on aluminium alloy plates (AA5083-H11 and AA5052-H32). The welding trials utilized a 2% Thoriated tungsten electrode, argon shielding gas, and precise welding parameters to ensure consistency. Tensile testing and microhardness measurements were employed to assess mechanical qualities, while optical and scanning electron microscopy was used to analyze microstructural features. ER5356 and ER5183 were the two filler rods that performed the best in terms of tensile strength (140.83 MPa and 100.21 MPa), elongation (7.62% and 4.01%), and weld joint efficiency (74.4% and 49.1%) respectively. The microhardness profiles revealed enhanced hardness in the weld zones with ER5183 (80Hv) and ER5356 (83Hv), attributed to the presence of magnesium, which contributed to grain refinement and improved mechanical properties. The findings highlight the critical role of filler material selection in achieving optimal weld quality. These results are particularly relevant for applications requiring high-strength and durable aluminum welds, such as in the aerospace, automotive, and marine industries, where structural integrity and performance are paramount. This study underscores the importance of choosing the appropriate filler rod to meet specific application requirements and ensure reliable welded structures.