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Title: Temperature-Dependent Configurational Entropy Calculations for Refractory High-Entropy Alloys
The cluster expansion formalism for alloys is used to construct surrogate models for three refractory high-entropy alloys (NbTiVZr, HfNbTaTiZr, and AlHfNbTaTiZr). These cluster expansion models are then used along with Monte Carlo methods and thermodynamic integration to calculate the configurational entropy of these refractory high-entropy alloys as a function of temperature. Many solid solution alloy design guidelines are based on the ideal entropy of mixing, which increases monotonically with N, the number of elements in the alloy. However, our results show that at low temperatures, the configurational entropy of these materials is largely independent of N, and the assumption described above only holds in the high-temperature limit. This suggests that alloy design guidelines based on the ideal entropy of mixing require further examination.
Authors:
; ;
Award ID(s):
2001411
Publication Date:
NSF-PAR ID:
10222508
Journal Name:
Journal of Phase Equilibria and Diffusion
ISSN:
1547-7037
Sponsoring Org:
National Science Foundation
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