High Strength and Ductility of Nanostructured Al Alloy 2024 Subjected to High Pressure Torsion

Abstract:

The structure and mechanical properties of Al-based alloy 2024 after high-pressure torsion (HPT) was investigated. Alloy 2024 with homogeneous structure and grain size about 70 nm was obtained using HPT at 6 GPa pressure and 5 turns of the anvils at room temperature. The nanostructured alloy possessed very high UTS (Ultimate tensile stress) above 1100 MPa at room temperature, and superplastic behaviour at temperatures over 300°С. The microhardness of the nanostructured alloy after superplastic deformation (1.5 GPa) was greater than that after the standard treatment of the coarse-grained alloy (1.2 GPa). The influence of HPT parameters and heat treatment on the structure and deformation behaviour of the alloy was studied. The opportunity of achieving a combination high strength and good ductility in metals and alloys opens perspectives for industrial applications, particularly, in micro-systems and for high-strength items with complex geometry which could be obtained by superplastic forming.

• Periodical: Solid State Phenomena (Volume 114)
• Pages: 85-90
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.114.85
• Online since: July 2006
• Authors: D. Vorona, Alfred V. Sharafutdinov, Nikolay A. Krasilnikov
• Keywords: High Pressure Torsion (HPT), Nanostructured Al-Based Alloy, Severe Plastic Deformation (SPD)

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