Short-Range Order in High-Entropy Alloys: First Principles Theory and Atomistic Modelling
Date:
Contributed poster at the 2022 Institute of Physics Theory of Condensed Matter (TCM) Group conference.
Abstract
Short-Range order (SRO) can be either beneficial or detrimental to the properties of novel high- and medium-entropy alloys. An understanding of phase behaviour and underlying physical mechanisms driving ordering is therefore essential. We present results from an all-electron, first principles, Landau-type theory which enables us to obtain SRO directly, and also to obtain parameters suitable for atomistic modelling to understand incipient order in these materials. As a case study, we present results on the prototypical face-centred cubic high-entropy alloy, NiCoFeMnCr, and its derivatives, collectively referred to as the Cantor-Wu alloys [1]. We are able to show that the dominant correlations in these systems are between Co and Cr, and that Fe and Mn dilute interactions and stabilise the disordered solid solution.
References
[1] C. D. Woodgate, J. B. Staunton, “Compositional Phase Stability in medium-entropy and high-entropy Cantor-Wu alloys from an ab initio all-electron Laundau-type theory and atomistic modelling”, Phys. Rev. B, 105, 115124 (2022).