Study on arc and laser powers in the hybrid welding of AA5754 Al-alloy

• 5754 Al-alloy weldability with a hybrid welding source was assessed.
• Weld porosity sensitiveness to laser and arc powers was demonstrated.
• Microstructure, residual stress and the mechanical properties were evaluated.
• The best levels of welding parameters were given in the investigated range.

In this paper a new generation of fiber laser assisted by a MIG source was used to weld AA5754-H111 aluminum alloy in 3 mm thick butt configuration. The effects of laser and arc powers on the weld geometry and properties were studied. Weld geometry and porosity were measured. The microstructure was investigated by optical microscope and Vickers micro-hardness was taken. The residual stress close to the heat affected zone was measured by the incremental hole-drilling method. Eventually, the tensile test was conducted in order to compare the mechanical properties of the weld with those of the parent metal.For the first time the sensitiveness of the hybrid welding of the 5754 aluminum alloy to the arc and laser powers was demonstrated. Higher laser power favored the stability of the process and provided good structural and geometrical properties of the weld. Further investigation can be performed in order to optimize the weld soundness and the energy efficiency of hybrid welding an aluminum alloy using a fiber laser.