Atomic short-range order and incipient long-range order in high-entropy alloys

Abstract

Within density-functional theory, we apply an electronic-structure-based thermodynamic theory to calculate short-ranged order (SRO) in homogeneously disordered substitutional N-component alloys, and its electronic origin. Using the geometric properties of an (N−1) simplex that describes the Gibbs (compositional) space, we derive the analytic transform of the SRO eigenvectors that provides a unique description of high-temperature SRO in N-component alloys and the incipient low-temperature long-range order. We apply the electronic-based thermodynamic theory and the new general analysis to ternaries (A1 CuNi-Zn and A2 Nb-Al-Ti) for validation, and then to quinary Al-Co-Cr-Fe-Ni high-entropy alloys for predictive assessment. Within density-functional theory, we apply an electronic-structure-based thermodynamic theory to calculate short-ranged order (SRO) in homogeneously disordered substitutional N -component alloys, and its electronic origin. Using the geometric properties of an (N − 1) simplex that describes the Gibbs (compositional) space, we derive the analytic transform of the SRO eigenvectors that provides a unique description of high-temperature SRO in N -component alloys and the incipient low-temperature long-range order. We apply the electronic-based thermodynamic theory and the new general analysis to ternaries (A1 Cu-Ni-Zn and A2 Nb-Al-Ti) for validation, and then to quinary Al-Co-Cr-Fe-Ni high-entropy alloys for predictive assessment. Keywords Materials Science and Engineering

Tailoring the physical properties of Ni-based single-phase equiatomic alloys by modifying the chemical complexity

“…Furthermore, calculated transport properties compared well with experimental values142124. In recent years, the CPA calculations have been successfully expanded to the applications in high entropy alloys, with majority of them focused on the structural, mechanical, defect, and magnetic properties252627282930.…”

Local Structure and Short-Range Order in a NiCoCr Solid Solution Alloy

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Statistical physics of multicomponent alloys using KKR-CPA

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“…(10) with G = G iµ ( ; r, r ) the site impurity Green function. The variation may be decomposed into three contributions:…”