The effect of severe plastic deformation on the natural ageing behavior of aluminum alloy 2024

Authors

• S. Khani Moghanaki
• M. Kazeminezhad

Abstract

The precipitation behavior and the hardness evolution of AA2024 under severe plastic deformation (SPD) and natural ageing have been studied. During SPD process, GPB zones/Cu-Mg co-clusters are dynamically precipitated. This is confirmed by elimination of GPB zones/Cu-Mg co-clusters formation effect in differential scanning calorimetery (DSC) study of deformed and undeformed samples. The occurrence of GPB zones or Cu-Mg co-clusters formation during SPD process reduces natural ageing kinetics of deformed samples. The formation of metastable phases at strain ~ 1 has been privileged in comparison with that of stable phases.

Keywords

• Natural ageing
• Severe plastic deformation
• AA2024

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