High Strength and Ductility of Nanostructured Al Alloy 2024 Subjected to High Pressure Torsion
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.
Witold Lojkowski and John R. Blizzard
D. Vorona et al., "High Strength and Ductility of Nanostructured Al Alloy 2024 Subjected to High Pressure Torsion ", Solid State Phenomena, Vol. 114, pp. 85-90, 2006