Analyzing the Influence of Titanium Content in 5087 Aluminum Filler Wires on Metal Inert Gas Welding Joints of AA5083 Alloy

As the demand for lightweight structures in the transportation industry continues to rise, AA5083 aluminum alloy has become increasingly prominent due to its superior corrosion resistance and weldability. To facilitate the production of high-quality, intricate AA5083 components, 5087 aluminum filler wire is commonly utilized in metal inert gas (MIG) welding processes for industrial applications. The optimization of filler wire composition is critical to enhancing the mechanical properties of AA5083 MIG-welded joints. This study investigates the effects of modifying 5087 aluminum filler wires with different titanium (Ti) contents on the microstructure and weldability of AA5083 alloy plates using MIG welding. The influence of Ti contents was systematically analyzed through comprehensive characterization techniques. The findings reveal that the constitutional supercooling induced by the Ti element and the formation of Al₃Ti facilitate the heterogeneous nucleation of α(Al), thereby promoting grain refinement. When the Ti content of 5087 filler wire is 0.1 wt.%, the grain size of the weld center was 78.48 μm. This microstructural enhancement results in the improved ductility of the AA5083 MIG-welded joints, with a maximum elongation of 16.64% achieved at 0.1 wt.% Ti addition. The hardness of the joints was the lowest in the weld center zone. This study provides critical insights into the role of Ti content in MIG welding and contributes to the advancement of high-performance filler wire formulations.