Effect of the aluminum alloy composition (Al-Cu-Li or Al-Mg-Li) on structure and mechanical properties of dissimilar laser welds with the Ti-Al-V alloy

This paper presents the results of the studies of dissimilar Ti-Al-V/Al-Cu-Li and Ti-Al-V/Al-Mg-Li laser welds. The main variable parameter was the laser offset towards the titanium alloy. It was found that strength properties of the welds were significantly affected by alloying elements (copper or magnesium) in the aluminum alloys. The presence of copper improved kinetics and thermodynamics of the welding process due to the formation of specific phases in the fusion zone. Also, it increased the strength of the dissimilar welds by 2.5 times compared with the Ti-Al-V/Al-Mg-Li joints.