Spin-driven ordering of Cr in the equiatomic high entropy alloy NiFeCrCo

Abstract

Spin-driven ordering of Cr in an equiatomic fcc NiFeCrCo high entropy alloy (HEA) was predicted by first-principles calculations. Ordering of Cr is driven by the reduction in energy realized by surrounding anti-ferromagnetic Cr with ferromagnetic Ni, Fe, and Co in an alloyed L12 structure. The fully Cr-ordered alloyed L12 phase was predicted to have a magnetic moment that is 36% of that for the magnetically frustrated random solid solution. Three samples were synthesized by milling or casting/annealing. The cast/annealed sample was found to have a low temperature magnetic moment that is 44% of the moment in the milled sample, which is consistent with theoretical predictions for ordering. Scanning transmission electron microscopy measurements were performed and the presence of ordered nano-domains in cast/annealed samples throughout the equiatomic NiFeCrCo HEA was identified.

Document Details

Document Type
Pub Defense Publication
Publication Date
Apr 20, 2015
Source ID
10.1063/1.4918996

Entities

People

  • A. A. Oni
  • A.J. Zaddach
  • C. C. Koch
  • Changning Niu
  • D. L. Irving
  • J. M. Lebeau
  • J. W. Hurt
  • X. Sang

Organizations

  • Air Force Office of Scientific Research
  • Furman University
  • National Science Foundation
  • North Carolina State University

Tags

Fields of Study

  • Physics

Readers

  • Ballistic Missile Meteorology
  • Materials Science and Engineering.

Technology Areas

  • Microelectronics