Artificial aging and shear deformation behaviour of 6022 aluminium alloy

In this study, the artificial aging behaviour of 6022-T4 alloy is investigated over a wide temperature range. Hardness readings, TEM and XRD analyses were performed. It was shown that 6022-T4 alloy can be substantially hardened through a short aging treatment at temperatures in excess of 200 °C. The strain hardening curves of the 6022 alloy in different aging conditions were measured using the simple shear test and analysed in terms of their respective microstructures. The under-aged and pre-peak-aged exhibited a good combination of strength and strain hardening while the peak-aged alloy was characterised by maximum strength, albeit with a drastic reduction in strain hardening ability. Strain reversal experiments in simple shear were carried out in order to characterize the Bauschinger effect for the different heat treatment conditions. It was shown that the T4 and under-aged conditions lead to permanent softening of the flow stress.