Influence of friction stir welding parameters on titanium-aluminum heterogeneous lap joining configuration

International audienceLap joining configuration for Friction Stir Welding process is a methodology mostly dedicated to heterogeneous bonding. This welding technology was applied to join pure titanium with 1050 aluminum alloy by varying the rotation speed and the movement speed of the tool. Regardless of the process parameters, it was found that the maximum strength of the junction remains almost constant. Microstructural observations by means of Scanning Electron Microscopy and Energy Dispersive Spectrometry analysis enable to describe the interfacial join and reveal asymmetric Cold Lap Defects on the sides of the junction. Chemical analysis shows the presence of one exclusive intermetallic compound through the interface identified as TiAl3. This compound is responsible of the crack spreading of the junction during the mechanical loading