Interstitial Carbon in bcc HfNbTiVZr high entropy alloy from first principles
Abstract
The remarkable mechanical properties of high entropy alloys can be further improved by interstitial alloying. In this work we employ density functional theory calculations to study the solution energies of dilute carbon interstitial atoms in tetrahedral and octahedral sites in bcc HfNbTiVZr. Our results indicate that carbon interstitials in tetrahedral sites are unstable, and the preferred octahedral sites present a large spread in the energy of solution. The inclusion of carbon interstitials induces large structural relaxations with long-range effects. The effect of local chemical environment on the energy of solution is investigated by performing a local cluster expansion including studies of its correlation with the carbon atomic Voronoi volume. However, the spread in solution energetics can not be explained with a local environment analysis only pointing towards a complex, long-range influence of interstitial carbon in this alloy.
Keywords
Cite
@article{arxiv.2010.01354,
title = {Interstitial Carbon in bcc HfNbTiVZr high entropy alloy from first principles},
author = {Luis Casillas-Trujillo and Ulf Jansson and Martin Sahlberg and Gustav Ek and Magnus M. Nygård and Magnus H. Sørby and Bjørn C. Hauback and Igor Abrikosov and Björn Alling},
journal= {arXiv preprint arXiv:2010.01354},
year = {2020}
}