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Updated: Jun 8, 2026

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Phonon softening on the specific heat of nanocrystalline metals
D P Rojas1, L Fernández Barquín, J Rodríguez Fernández
1CITIMAC, Facultad de Ciencias, Universidad de Cantabria, Santander, Spain. rojasd@unican.es
Abstract:
Specific heat enhancement in several common nanocrystalline metals is established by comparison with their bulk counterparts. Measurements were carried out in Fe, Cu, Ni and binary alloy LaAl(2). The excess specific heat is evidenced as a low temperature peak below 65 K and a high temperature slope above 150 K. The experimental data are in good agreement with a model which considers contributions from the grain boundary and core atoms in the nanoparticles. This model is supported by Raman spectroscopy measurements, showing a softening of the frequency phonon modes associated with a size reduction and increase of the atomic disorder.
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