CO<sub>2</sub> Laser - MIG Hybrid Welding of Titanium Alloy

CO2 laser - Metal Inert Gas (MIG) hybrid welding process was investigated in the butt welding of Ti-6Al-4V titanium alloy sheets of 3.0mm in thickness. Using a Design of Experiment (DoE) approach, bead on plate tests were planned with the aim to analyze the effect of laser and laser-MIG welding parameters on the bead shape, hardness profiles in the weld cross section and welding efficiency. Butt welds performed in correspondence of the bead on plate working conditions which assure the complete penetration of the samples, the absence of undercuts and the maximum welding efficiency, confirm the results of the bead on plate tests and highlights the gap bridging ability of the hybrid welding process.