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The geometry, topology and structure of amorphous solids / Cheuk-Yu Lee in Acta materialia, Vol. 58 N° 2 (Janvier 2010) 

Public ISBD [article]  in Acta materialia > Vol. 58 N° 2 (Janvier 2010) . - pp. 615-625 Titre : The geometry, topology and structure of amorphous solids Type de document : texte imprimé Auteurs : Cheuk-Yu Lee, Auteur ; Zbigniew H. Stachurski, Auteur ; T. Richard Welberry, Auteur Article en page(s) : pp. 615-625 Note générale : Métallurgie Langues : Anglais (eng) Mots-clés : Cluster  topology  Multiatomic  glass  Debye  scattering  Amorphousness Index. décimale : 669 Métallurgie Résumé : Clusters of atoms can be divided into three categories depending on their topology. One of the categories provides the basis for development of a model of a perfectly random structure (ideal amorphous solid) using the non-equilateral triangle topology in the coordination shell. Metallic glasses solidify as amorphous solids with random arrangement of atoms. A model of Zr-based metallic glass has been constructed and described in terms of cluster topology, and compared with a recently published dynamic molecular model of the same alloy. It is shown that the pair distribution function for the ideal amorphous model relates to the pair correlation function obtained from the dynamic model. Debye X-ray scattering computations reveal the presence of vacancies and other flaws relative to the ideal amorphous solid. A shift in the peak position can be predicted using the Erhenfest formula. Two atomic displacement mechanisms involving a five-atom sub-cluster are identified as the fundamental means of compositional redistribution between clusters in the alloy. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science?_ob=PublicationURL&_tockey=%23TOC%235556%23 [...] [article] The geometry, topology and structure of amorphous solids [texte imprimé] / Cheuk-Yu Lee, Auteur ; Zbigniew H. Stachurski, Auteur ; T. Richard Welberry, Auteur . - pp. 615-625. Métallurgie Langues : Anglais (eng) in Acta materialia > Vol. 58 N° 2 (Janvier 2010) . - pp. 615-625 Mots-clés : Cluster  topology  Multiatomic  glass  Debye  scattering  Amorphousness Index. décimale : 669 Métallurgie Résumé : Clusters of atoms can be divided into three categories depending on their topology. One of the categories provides the basis for development of a model of a perfectly random structure (ideal amorphous solid) using the non-equilateral triangle topology in the coordination shell. Metallic glasses solidify as amorphous solids with random arrangement of atoms. A model of Zr-based metallic glass has been constructed and described in terms of cluster topology, and compared with a recently published dynamic molecular model of the same alloy. It is shown that the pair distribution function for the ideal amorphous model relates to the pair correlation function obtained from the dynamic model. Debye X-ray scattering computations reveal the presence of vacancies and other flaws relative to the ideal amorphous solid. A shift in the peak position can be predicted using the Erhenfest formula. Two atomic displacement mechanisms involving a five-atom sub-cluster are identified as the fundamental means of compositional redistribution between clusters in the alloy. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science?_ob=PublicationURL&_tockey=%23TOC%235556%23 [...]