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HRTEM and EELS study of aluminum nitride in nanostructured Al 5083/B4C processed via cryomilling / Y. Li in Acta materialia, Vol. 58 N° 5 (Mars 2010) 

Public ISBD [article]  in Acta materialia > Vol. 58 N° 5 (Mars 2010) . - pp. 1732–1740 Titre : HRTEM and EELS study of aluminum nitride in nanostructured Al 5083/B4C processed via cryomilling Type de document : texte imprimé Auteurs : Y. Li, Auteur ; W. Liu, Auteur ; V. Ortalan, Auteur Année de publication : 2011 Article en page(s) : pp. 1732–1740 Note générale : Métallurgie Langues : Anglais (eng) Mots-clés : High-resolution  electron  microscopy  (HREM)  Electron  energy  loss  spectroscopy  (EELS)  Transmission  electron  microscopy  (TEM)  Particulate  reinforced  composites  Metal  matrix  composites  (MMC) Résumé : The presence of aluminum nitride in nanostructured aluminum metal matrix composites was studied by high resolution transmission electron microscopy, electron energy loss spectroscopy, energy dispersive X-ray spectroscopy analysis and electron microscopy simulations. Three types of aluminum nitride structures were identified; predominantly, one layer of N atoms occupies the tetrahedral interstitial positions in the Al lattice, the frequency of which varies as a function of spatial location. The second and third were in the form of hexagonal and possibly cubic aluminum nitride particles with particle sizes on the order of 15–20 nm. The results suggest that the aluminum nitride phase evolves from intermediate transitional structures that involve N atoms in the Al lattice. The aluminum nitride phases frequently contained O and Mg, which preferentially segregate in close proximity to the reinforcement particles. First-principle calculations were used to describe the influence of O and Mg on the adsorption of N. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645409007940 [article] HRTEM and EELS study of aluminum nitride in nanostructured Al 5083/B4C processed via cryomilling [texte imprimé] / Y. Li, Auteur ; W. Liu, Auteur ; V. Ortalan, Auteur . - 2011 . - pp. 1732–1740. Métallurgie Langues : Anglais (eng) in Acta materialia > Vol. 58 N° 5 (Mars 2010) . - pp. 1732–1740 Mots-clés : High-resolution  electron  microscopy  (HREM)  Electron  energy  loss  spectroscopy  (EELS)  Transmission  electron  microscopy  (TEM)  Particulate  reinforced  composites  Metal  matrix  composites  (MMC) Résumé : The presence of aluminum nitride in nanostructured aluminum metal matrix composites was studied by high resolution transmission electron microscopy, electron energy loss spectroscopy, energy dispersive X-ray spectroscopy analysis and electron microscopy simulations. Three types of aluminum nitride structures were identified; predominantly, one layer of N atoms occupies the tetrahedral interstitial positions in the Al lattice, the frequency of which varies as a function of spatial location. The second and third were in the form of hexagonal and possibly cubic aluminum nitride particles with particle sizes on the order of 15–20 nm. The results suggest that the aluminum nitride phase evolves from intermediate transitional structures that involve N atoms in the Al lattice. The aluminum nitride phases frequently contained O and Mg, which preferentially segregate in close proximity to the reinforcement particles. First-principle calculations were used to describe the influence of O and Mg on the adsorption of N. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645409007940