Study of hot deformation of an Al-Cu-Mg alloy using processing maps and microstructural characterization

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:552

Article

Cepeda-Jimenez, C. M.¹  Ruano, O. A.¹  Carsi, M.¹  Carreno, F.¹ 

[1] CSIC, Dept Met Phys, CENIM, Madrid 28040, Spain

关键词: Electron backscatter diffraction-EBSD;    Mechanical characterization;    Aluminium alloys;    Hot deformation;    Recrystallization;    Processing maps;   

DOI  :  10.1016/j.msea.2012.05.082

来源: Elsevier

【 摘 要 】

The forming behaviour of an Al-Cu-Mg alloy (Al 2024-T351) has been studied by processing maps and microstructural characterization. Torsion tests were conducted in the range 278-467 degrees C, between 2.1 and 25.6 s(-1). Stress-strain curves obtained from the experiment data were fitted using the Garofalo equation to obtain the constitutive parameters, obtaining a stress exponent of 6.1 and an activation energy of 180 kJ/mol. Electron backscatter diffraction (EBSD) was employed to characterize the microtexture and microstructure, before and after torsion testing, to evaluate the microstructural changes and instability phenomena. A peak ductility of the Al 2024 alloy was found at about 400 degrees C at all strain rates considered. According to the processing maps and microstructure observation, the optimum hot deformation condition for the Al 2024 alloy is in the range 360-410 degrees C and 2.1-4.5 s(-1). Under these favourable conditions a uniform and fine grain size is obtained by extended dynamic recovery (DRV), which leads to the formation of subgrain boundaries that progressively transform at large strains into new high angle grain boundaries. (c) 2012 Elsevier B.V. All rights reserved.

【 授权许可】

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