Studying Weldability in Semi-Finished Products Made of an Al–Mg–Si–Cu Alloy

Features of the formation of the microstructure in welding joints made at various parameters of automatic argon-arc welding in sheets of V-1381 aluminum alloy (Al–Mg–Si–Cu system) were explored. The welding conditions were selected to ensure a high-quality welding and a strength of no lower than 0.8 of the base metal. It was determined that welding without filler wire results in fracturing even without applying tensile deformation. The use of Sv1221 filler wire instead of SvAMg61 and SvAK5 wires increased the strength parameters of welded joints by about 15–20%. The corrosion resistance of welded joints made of V-1381 alloy sheets was estimeted. Various experimental conditions of laser welding were tested, and the microstructure and mechanical properties of the obtained welds were studied. The parameters ensuring high quality of welds were chosen. The possibility of using laser welding of semi-finished products made of V-1381 alloy was determined. New V-1381 alloy can be recommended for making structural elements of aircraft fuselage, in particular, as an alternative to less corrosion-resistant non-weldable D16 alloys, which will improve the weight efficiency of the structures due to both higher strength and the use of welded, rather than riveted, joints.