Autogenous Yb:YAG laser disk welding domain of AA6061-T4 aluminium alloy

Abstract— The aerospace industry is developing lighter, stronger and more heat- and corrosion-resistant components to reduce manufacturing costs and fuel consumption. To achieve this goal, laser welding represents a real opportunity to replace the riveting assemblies developed in the 1920s. In this article, we present our research to obtain the weldability domain of AA6061 aluminium alloy by autogenous disk laser welding. A systematic study of the samples butt-welded by X-ray and optical microscopy allowed us to determine the defects and the dimensions of the weld beads according to the process parameters. The data analysis with the CORICO software made it possible to determine the regression models considering the welding parameters in order to avoid the appearance of defects such as melt pool collapse, lack of penetration or hot cracking. A range of weldability was defined for power values between 2000 to 2500 W, welding speeds below 4m/min and focal diameters below 170 microns.