Connections Between Magnetism and Preferred Atomic Arrangements in Multicomponent Alloys: Insights From An All-Electron Linear Response Theory

Date:

Contributed talk at the 2024 CCP9 Conference and Community Meeting. CCP9 is the UK’s electronic structure network.

Abstract

Metallic alloys remain a fundamental and fascinating class of materials to study, as systems which are both of fundamental physical interest and also of use in an enormous range of technologically relevant applications. An important question to address when modelling these systems is: can the phase behaviour of a given system be successfully predicted without reliance on empirical data? In this talk, I will present results from an ab initio, all-electron, Landau-type theory [1,2] suited for modelling the phase behaviour of a wide class of alloy systems, which is based density functional calculations of materials’ electronic structure. In particular, I will demonstrate the importance of the correct treatment of magnetism when modelling these systems, showing how both the nature and predicted temperature of atomic ordering are dramatically affected based on the simulated magnetic state. We will consider example systems including the pathological, 3-component, CrCoNi alloy [3], as well as the technologically relevant binary FeNi system [4], the ordered state of which is under consideration as a candidate rare-earth-free permanent magnet.

References

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

[2] C. D. Woodgate, 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).

[4] C. D. Woodgate, L. H. Lewis, J. B. Staunton, arXiv:2401.02809.