Interplay Between Magnetism and Short-Range Order in Medium- and High-Entropy Alloys: CrCoNi, CrFeCoNi, and CrMnFeCoNi

Date:

Contributed talk at the 2025 Joint MMM-Intermag Conference.

Abstract

We present computational results suggesting a potential route for tuning atomic ordering in medium- and high-entropy alloys, by annealing samples in an applied magnetic field and thus altering the magnetic state. Controlling atomic order is critical for tuning materials properties, and our approach is anticipated to open up new routes for discovery of novel materials. Specifically, the impact of magnetism on predicted atomic short-range order in Ni-based high-entropy alloys is studied using a first-principles, all- electron, Landau-type linear response theory, coupled with lattice-based atomistic modelling [1,2]. We perform two sets of linear-response calculations: one in which the paramagnetic state is modelled within the disordered local moment picture, and one in which systems are modelled in a magnetically ordered state. We show that the treatment of magnetism can have significant impact both on the predicted temperature of atomic ordering and also the nature of atomic order itself [3]. In CrCoNi, we find that the nature of atomic order changes from being L12-like when modelled in the paramagnetic state to MoPt2-like when modelled assuming the system has magnetically ordered. In CrFeCoNi, atomic correlations between Fe and the other elements present are dramatically strengthened when we switch from treating the system as magnetically disordered to magnetically ordered. Our results show it is necessary to consider the magnetic state when modelling multicomponent alloys containing mid- to late-3d elements, and we suggest that, potentially, there could be a variety of multicomponent alloy compositions containing 3d transition metals that will exhibit specific atomic ordering when thermally treated in an applied magnetic field.

References

[1] C. D. Woodgate and J. B. Staunton, Phys. Rev. B 105, 115124 (2022).

[2] C. D. Woodgate and J. B. Staunton, Phys. Rev. Mater. 7 013801 (2023).

[3] C. D. Woodgate D. Hedlund, L. H. Lewis, J. B. Staunton, Phys. Rev. Mater. 7, 053801 (2023).

Acknowledgments

Research supported by the U.S. Department of Energy, Office of Basic Energy Sciences under Award Number DE SC0022168 (for atomic insight) and by the UK Engineering and Physical Sciences Research Council, Grant No. EP/W021331/1 and the U.S. National Science Foundation under Award ID 2118164 (for advanced manufacturing aspects).