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

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 ◦C, between 2.1 and 25.6 s−1. Stress–strain curves obtained from the experiment data were fitted using the Garofalo eq...

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Detalles Bibliográficos
Autores: Cepeda-Jiménez, C.M., Ruano, Oscar Antonio, Carsí, Manuel, Carreño, Fernando
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2012
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/109997
Acceso en línea:http://hdl.handle.net/10261/109997
Access Level:acceso abierto
Palabra clave:Electron backscatter diffraction-EBSD
Mechanical characterization
Aluminium alloys
Hot deformation
Recrystallization
Processing maps
Descripción
Sumario: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 ◦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 ◦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 ◦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