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

Pure Ti powders were subjected to ball milling and subsequently high-pressure torsion (HPT) for consolidation. It is found that a fully dense (99.9%) disc with ultrafine grained structure (~50-300 nm) was produced. The strength and ductility were well comparable to those of ball-milled Ti-6%Al-4%V powders after hot roll sintering.

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

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.114.85 ◽

2006 ◽

Vol 114 ◽

pp. 85-90 ◽

Cited By ~ 3

Author(s):

D. Vorona ◽

Alfred V. Sharafutdinov ◽

Nikolay A. Krasilnikov

Keyword(s):

High Pressure ◽

Room Temperature ◽

Complex Geometry ◽

High Pressure Torsion ◽

Deformation Behaviour ◽

Superplastic Forming ◽

High Strength ◽

Industrial Applications ◽

Coarse Grained ◽

Al Alloy

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.

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An Overview on the Fracture Behavior of Metals Processed by High Pressure Torsion

Materials Science Forum ◽

10.4028/www.scientific.net/msf.667-669.671 ◽

2010 ◽

Vol 667-669 ◽

pp. 671-676 ◽

Cited By ~ 4

Author(s):

Anton Hohenwarter ◽

Reinhard Pippan

Keyword(s):

Fracture Toughness ◽

High Pressure ◽

Fracture Behavior ◽

High Pressure Torsion ◽

High Strength ◽

High Fracture Toughness ◽

High Fracture ◽

Ultrafine Grained ◽

Specimen Orientation ◽

Strength And Ductility

Motivated by the large variety of enhanced properties of ultrafine and nanocrystalline materials such materials are under extensive investigation. Besides focusing on classical material parameters, like strength and ductility, the fracture toughness of these materials is also of great importance, especially when the damage tolerance is required. In this contribution an overview of the fracture behavior of different metals covering ultrafine-grained iron and nickel as well as a nanocrystalline steel processed via high pressure torsion (HPT) will be given. It will be shown that the specimen orientation can have a tremendous influence on the fracture behavior and toughness. Due to this toughness anisotropy an unexpectedly good combination of high strength and high fracture toughness can be achieved very often in these materials.

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