TWI

The weldability of 2 mm thickness thixomoulded sheets of AZ91D magnesium alloy by friction stir welding (FSW) was studied as a function of tool rotation speed (880-1750 rpm) and specimen travel speed (50-500 mm/min). The composition of the sheet was Mg, 9.17%Al, 0.65%Zn, 0.28%Mn, 0.02%Si, 0.002%Fe, 0.002%Cu, 0.001%Ni. Weld defects were evaluated by visual and X-ray radiography inspections. The mechanical properties (hardness, tensile strength) of the friction stir welds were examined. The optimum FSW conditions for welding AZ91D were determined. Higher travel speed or lower rotation speed than optimum conditions caused an inner void or lack of bonding in the stir zone.

3rd International Symposium, 27-28 Sep 2001, Session 2: Non-Aluminium Alloys, Paper 03