TWI

Friction stir welding (FSW) was employed to undertake lap joining of very thin sheets (thickness 1 mm) of aluminium alloys and a structural steel using different tool geometries and a wide range of process parameters, and the microstructure and mechanical properties of the welded joints were investigated. The grades studied were AA 6082-T6 and AA 5754-H22 alloys and DX51D-Z galvanised steel. Two FSW tools were used, one with a conical shoulder and the other with a scrolled shoulder. Welding was performed at rotational speeds of 1200-2000 rpm or 600 rpm and travel speeds of 75-350 mm/min or 250 mm/min for aluminium alloys and steel, respectively. The welded joints were examined by surface inspection and the microstructure was observed by optical microscopy. The mechanical properties of the HAZ and TMAZ (thermomechanically affected zone) were characterised by hardness measurements and tensile tests.

10th International Symposium, 20-22 May 2014, Session 4A: Techniques I, Paper 03