Polyamorphism in cerium based bulk metallic glasses: Electronic and structural properties under pressure and temperature by x-ray absorption techniques
Langue
en
Article de revue
Ce document a été publié dans
Applied Physics Letters. 2013, vol. 103, n° 11, p. 111905
American Institute of Physics
Résumé en anglais
High pressure and high temperature x-ray absorption near edge spectroscopy experiments have been carried out on Ce60Al20Cu20 bulk metallic glass showing an electronic delocalization of the 4f-electron of cerium under ...Lire la suite >
High pressure and high temperature x-ray absorption near edge spectroscopy experiments have been carried out on Ce60Al20Cu20 bulk metallic glass showing an electronic delocalization of the 4f-electron of cerium under pressure. In parallel, high pressure extended x-ray absorption fine structure spectroscopy reveals large structural modifications of the cerium local environment. This study provides experimental evidence that an electronic driven structural transformation occurs in cerium based bulk metallic glasses (Ce-BMGs). The effect of temperature on the hysteresis of this amorphous-amorphous phase transition is also discussed, suggesting the existence of a critical point in the phase diagram of Ce-BMGs. This work will encourage further investigations on Ce-based metallic glasses phase diagrams in order to support, or refute, the actual theoretical understanding of polyamorphism.< Réduire
Mots clés en anglais
Aluminium alloys
Amorphous state
Cerium alloys
Copper alloys
EXAFS
Glass transition
High-pressure solid-state phase transformations
High-temperature effects
Metallic glasses
Polymorphism
XANES
Origine
Importé de halUnités de recherche