[article] 
					| Titre : | 
					Development of novel grain morphology during hot extrusion of magnesium AZ21 alloy | 
				 
					| Type de document :  | 
					texte imprimé | 
				 
					| Auteurs :  | 
					M. A. Azeem, Auteur ; A. Tewari, Auteur ; S. Mishra, Auteur | 
				 
					| Année de publication :  | 
					2011 | 
				 
					| Article en page(s) :  | 
					pp. 1495–1502 | 
				 
					| Note générale :  | 
					Métallurgie | 
				 
					| Langues : | 
					Anglais (eng) | 
				 
					| Mots-clés :  | 
					Magnesium alloy Extrusion Dynamic recrystallization Annealing Electron backscattering diffraction (EBSD) | 
				 
					| Résumé :  | 
					Microstructure and microtexture evolution during static annealing of a hot-extruded AZ21 magnesium alloy was studied. Apart from fine recrystallized equiaxed grains and large elongated deformed grains, a new third kind of abnormal grains that are stacked one after the other in a row parallel to the extrusion direction were observed. The crystallographic misorientation inside these grains was similar to that of the fine recrystallized grains. The large elongated grains exhibited significant in-grain misorientation. A self-consistent mechanistic model was developed to describe the formation of these grain morphologies during dynamic recrystallization (DRX). The texture of pre-extruded material, although lost in DRX, leaves a unique signature which manifests itself in the form of these grain morphologies. The origin of abnormal stacked grains was associated with slow nucleation in pre-extruded grains of a certain orientation. Further annealing resulted in large secondary recrystallized grains with occasional extension twins. | 
				 
					| DEWEY :  | 
					669 | 
				 
					| ISSN :  | 
					1359-6454 | 
				 
					| En ligne :  | 
					http://www.sciencedirect.com/science/article/pii/S1359645409007599 | 
				  in Acta materialia > Vol. 58 N° 5  (Mars 2010) . - pp. 1495–1502 
 
					[article] Development of novel grain morphology during hot extrusion of magnesium AZ21 alloy [texte imprimé] /  M. A. Azeem, Auteur ;  A. Tewari, Auteur ;  S. Mishra, Auteur . - 2011 . - pp. 1495–1502. Métallurgie Langues : Anglais ( eng) in Acta materialia >  Vol. 58 N° 5  (Mars 2010) . - pp. 1495–1502 
					| Mots-clés :  | 
					Magnesium alloy Extrusion Dynamic recrystallization Annealing Electron backscattering diffraction (EBSD) | 
				 
					| Résumé :  | 
					Microstructure and microtexture evolution during static annealing of a hot-extruded AZ21 magnesium alloy was studied. Apart from fine recrystallized equiaxed grains and large elongated deformed grains, a new third kind of abnormal grains that are stacked one after the other in a row parallel to the extrusion direction were observed. The crystallographic misorientation inside these grains was similar to that of the fine recrystallized grains. The large elongated grains exhibited significant in-grain misorientation. A self-consistent mechanistic model was developed to describe the formation of these grain morphologies during dynamic recrystallization (DRX). The texture of pre-extruded material, although lost in DRX, leaves a unique signature which manifests itself in the form of these grain morphologies. The origin of abnormal stacked grains was associated with slow nucleation in pre-extruded grains of a certain orientation. Further annealing resulted in large secondary recrystallized grains with occasional extension twins. | 
				 
					| DEWEY :  | 
					669 | 
				 
					| ISSN :  | 
					1359-6454 | 
				 
					| En ligne :  | 
					http://www.sciencedirect.com/science/article/pii/S1359645409007599 | 
				 
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