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

Subject Areas : journal of New Materials

S. Khani Moghanaki ¹ (دانشجوی دکترای دانشکده مهندسی و علم مواد-دانشگاه صنعتی شریف-تهران-ایران)
M. Kazeminezhad ² (استاد دانشکده مهندسی و علم مواد-دانشگاه صنعتی شریف- تهران-ایران)

Received: 2016-07-26 Accepted : 2016-07-26 Published : 2016-04-20

Keywords: Severe plastic deformation, Natural ageing, AA2024,

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.

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