TWI

With regard to the application of friction stir welding (FSW) of ultra thin aluminium sheets (thickness less than 1 mm) to electronic packaging and micromechanical component joining, an investigation is presented into fixturing, process parameter and heat input demands of ultra thin sheets for achieving sound welded joints. FSW experiments were conducted on thin and ultra thin sheets (thickness 1 and 0.5 mm, respectively) of AA 6061-T6 aluminium alloys. Process parameters (tool rotational speed, travel speed and plunge depth) were optimised using the Taguchi method. The heat input per unit volume was calculated with respect to the optimal set of process parameters in each sheet thickness. Mechanical properties were characterised by tensile tests. Issues discussed include buckling distortion in micro-FSW resulting from induced compressive bending stress, the microstructure of different weld zones and the temperature distribution during ultra thin sheet welding.

12th International Symposium, 26-28 Jun 2018, Session 4B: Performance I, Paper 02