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Primary crystallization in Al-rich metallic glasses at unusually low temperatures / J. Bokeloh in Acta materialia, Vol. 58 N° 11 (Juin 2010) 

Public ISBD [article]  in Acta materialia > Vol. 58 N° 11 (Juin 2010) . - pp. 3919–3926 Titre : Primary crystallization in Al-rich metallic glasses at unusually low temperatures Type de document : texte imprimé Auteurs : J. Bokeloh, Auteur ; N. Boucharat, Auteur ; H. Rösner, Auteur Année de publication : 2011 Article en page(s) : pp. 3919–3926 Note générale : Métallurgie Langues : Anglais (eng) Mots-clés : Nanocrystallization  Metallic  glasses  Modulated  differential  scanning  calorimetry  Phase  separation Résumé : The initial stage of the primary crystallization reaction and the glass transition of the marginal metallic glass Al89Y6Fe5 were investigated by conventional differential scanning calorimetry (DSC) and modulated differential scanning calorimetry (MDSC), microcalorimetry, X-ray diffraction (XRD) and transmission electron microscopy. A sharp onset of the primary crystallization was found by microcalorimetry and XRD studies at temperatures which were 120 °C below the primary crystallization peak observed in conventional DSC. A systematic MDSC study of annealed samples revealed a wide spectrum of glass transition onsets, which show a strong dependence on the annealing conditions. In addition, the glass transition onsets can be linked to the initial stage of the primary crystallization. The spectrum of glass transition onsets observed is discussed with respect to the occurrence of phase separation preceding the nucleation and growth of dendritic aluminium nanocrystals. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645410001904 [article] Primary crystallization in Al-rich metallic glasses at unusually low temperatures [texte imprimé] / J. Bokeloh, Auteur ; N. Boucharat, Auteur ; H. Rösner, Auteur . - 2011 . - pp. 3919–3926. Métallurgie Langues : Anglais (eng) in Acta materialia > Vol. 58 N° 11 (Juin 2010) . - pp. 3919–3926 Mots-clés : Nanocrystallization  Metallic  glasses  Modulated  differential  scanning  calorimetry  Phase  separation Résumé : The initial stage of the primary crystallization reaction and the glass transition of the marginal metallic glass Al89Y6Fe5 were investigated by conventional differential scanning calorimetry (DSC) and modulated differential scanning calorimetry (MDSC), microcalorimetry, X-ray diffraction (XRD) and transmission electron microscopy. A sharp onset of the primary crystallization was found by microcalorimetry and XRD studies at temperatures which were 120 °C below the primary crystallization peak observed in conventional DSC. A systematic MDSC study of annealed samples revealed a wide spectrum of glass transition onsets, which show a strong dependence on the annealing conditions. In addition, the glass transition onsets can be linked to the initial stage of the primary crystallization. The spectrum of glass transition onsets observed is discussed with respect to the occurrence of phase separation preceding the nucleation and growth of dendritic aluminium nanocrystals. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645410001904