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Plastic deformation mechanism of ultra-fine-grained AA6063 processed by equal-channel angular pressing / Tao Qian in Acta materialia, Vol. 58 N° 6 (Avril 2010) 

Public ISBD [article]  in Acta materialia > Vol. 58 N° 6 (Avril 2010) . - pp. 2112–2123 Titre : Plastic deformation mechanism of ultra-fine-grained AA6063 processed by equal-channel angular pressing Type de document : texte imprimé Auteurs : Tao Qian, Auteur ; Michael Marx, Auteur ; Kerstin Schüler, Auteur Année de publication : 2011 Article en page(s) : pp. 2112–2123 Note générale : Métallurgie Langues : Anglais (eng) Mots-clés : UFG  material  ECAP  Backscatter  contrast  Electron  backscatter  diffraction  Scanning  TEM Résumé : Equal-channel angular pressing (ECAP) is an established method to produce ultra-fine-grained (UFG) materials with extraordinary mechanical properties. However, different methods to characterize the complex microstructure give contradictory results. Therefore an ECAP-processed UFG aluminum alloy AA6063 was characterized by various electron-microscopy-based methods such as backscattered electron contrast, electron backscatter diffraction, transmission electron microscopy and low-voltage scanning transmission electron microscopy. Only a skilful combination of all methods reveals the complete information about the microstructure which is needed to understand the results of the mechanical testing by nanoindentation, tensile tests and strain-rate jump test. The main difference is the amount of low-angle grain boundaries and high-angle grain boundaries which determine hardness, tensile and yield strength and strain-rate sensitivity of ECAP materials produced by different numbers of passes and routes. This is explained by the interaction of dislocations with the different grain boundaries. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645409008325 [article] Plastic deformation mechanism of ultra-fine-grained AA6063 processed by equal-channel angular pressing [texte imprimé] / Tao Qian, Auteur ; Michael Marx, Auteur ; Kerstin Schüler, Auteur . - 2011 . - pp. 2112–2123. Métallurgie Langues : Anglais (eng) in Acta materialia > Vol. 58 N° 6 (Avril 2010) . - pp. 2112–2123 Mots-clés : UFG  material  ECAP  Backscatter  contrast  Electron  backscatter  diffraction  Scanning  TEM Résumé : Equal-channel angular pressing (ECAP) is an established method to produce ultra-fine-grained (UFG) materials with extraordinary mechanical properties. However, different methods to characterize the complex microstructure give contradictory results. Therefore an ECAP-processed UFG aluminum alloy AA6063 was characterized by various electron-microscopy-based methods such as backscattered electron contrast, electron backscatter diffraction, transmission electron microscopy and low-voltage scanning transmission electron microscopy. Only a skilful combination of all methods reveals the complete information about the microstructure which is needed to understand the results of the mechanical testing by nanoindentation, tensile tests and strain-rate jump test. The main difference is the amount of low-angle grain boundaries and high-angle grain boundaries which determine hardness, tensile and yield strength and strain-rate sensitivity of ECAP materials produced by different numbers of passes and routes. This is explained by the interaction of dislocations with the different grain boundaries. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645409008325