On the martensitic transformation in Fe${}_x$Mn${}_{80-x}$Co${}_{10}$Cr${}_{10}$ high-entropy alloy

Abstract

High-entropy alloys (HEAs), and even medium-entropy alloys (MEAs), are an intriguing class of materials in that structure and property relations can be controlled via alloying and chemical disorder over wide ranges in the composition space. Employing density-functional theory combined with the coherent-potential approximation to average over all chemical configurations, we tune free energies between face-centered-cubic (fcc) and hexagonal-close-packed (hcp) phases in Fe${}_x$Mn${}_{80-x}$Co${}_{10}$Cr${}_{10}$ systems.~Within Fe-Mn-based alloys, we show that the martensitic transformation and chemical short-range order directly correlate with the fcc-hcp energy difference and stacking-fault energies, which are in quantitative agreement with recent experiments on a $x$=40~at.\% polycrystalline HEA/MEA. Our predictions are further confirmed by single-crystal measurements on a$x$=40at.\% using transmission-electron microscopy, selective-area diffraction, and electron-backscattered-diffraction mapping. The results herein offer an understanding of transformation-induced/twinning-induced plasticity (TRIP/TWIP) in this class of HEAs and a design guide for controlling the physics behind the TRIP effect at the electronic level.

arXiv comment6 pages, 5 figures, 1 table

References in corpus (9)

• Verification of Short-Range Order and Its Impact on the Properties of the CrCoNi Medium Entropy Alloy
• Tunable stacking fault energies by tailoring local chemical order in CrCoNi medium-entropy alloys
• Hybrid Monte Carlo/molecular dynamics simulation of a refractory metal high entropy alloy
• Design of high-strength refractory complex solid-solution alloys
• First-principles concentration-wave approach to predict incipient order in high-entropy alloys: case of Ti${}_{0.25}$CrFeNiAl${}_x$
• Ta-Nb-Mo-W refractory high-entropy alloys: anomalous ordering behavior and its intriguing electronic origin
• Vacancy-mediated complex phase selection in high entropy alloys
• Structural Properties and Relative Stability of (Meta)Stable Ordered, Partially-ordered and Disordered Al-Li Alloy Phases
• Tuning phase-stability and short-range order through Al-doping in (CoCrFeMn)100-xAlx high entropy alloys

Cited by in corpus (3)

• Towards Stacking Fault Energy Engineering in FCC High Entropy Alloys
• Short-range order and compositional phase stability in refractory high-entropy alloys via first principles theory and atomistic modelling: NbMoTa, NbMoTaW and VNbMoTaW
• Compositional phase stability in medium-entropy and high-entropy Cantor-Wu alloys from an ab initio all-electron, Landau-type theory and atomistic modelling