TWI

Dissimilar joints between wrought 5083 and 6111 aluminium alloys and between AZ31 magnesium alloy and 6111 were fabricated by friction stir welding and their microstructure and mechanical properties were investigated. The starting materials were 5083-H111, 6111-T4 and AZ31-H24 sheets with thicknesses of 1.6, 1.5 and 2 mm, respectively. Welding was performed at a tool rotational speed of 1500 rpm and traverse speeds of 350 mm/min and 75 mm/min for the Al/Al and Mg/Al joints, respectively. Macrostructures and microstructures were observed by optical microscopy. Mechanical properties were characterised by microhardness profile measurements, quasistatic performance assessment using an Instron screw-driven testing machine, fatigue testing of lap shear coupons on an MTS servo hydraulic load frame and fracture surface observations.

11th International Symposium, 17-19 May 2016, Session 9B: Microstructure and Dissimilar, Paper 02