Abstract
Magnetic materials with excellent performances are desired for functional applications. Based on the high-entropy effect, a system of CoFeMnNiX (X = Al, Cr, Ga, and Sn) magnetic alloys are designed and investigated. The dramatic change in phase structures from face-centered-cubic (FCC) to ordered body-centered-cubic (BCC) phases, caused by adding Al, Ga, and Sn in CoFeMnNiX alloys, originates from the potent short-range chemical order in the liquid state predicted by ab initio molecular dynamics (AIMD) simulations. This phase transition leads to the significant enhancement of the saturation magnetization (Ms), e.g., the CoFeMnNiAl alloy has Msof 147.86 Am2/kg. First-principles density functional theory (DFT) calculations on the electronic and magnetic structures reveal that the anti-ferromagnetism of Mn atoms in CoFeMnNi is suppressed especially in the CoFeMnNiAl HEA because Al changes the Fermi level and itinerant electron-spin coupling that lead to ferromagnetism.
| Original language | English |
|---|---|
| Pages (from-to) | 10-18 |
| Number of pages | 9 |
| Journal | Acta Materialia |
| Volume | 130 |
| DOIs | |
| State | Published - May 15 2017 |
Funding
This project was supported by the National High Technology Research and Development Program of China (No. 2009AA03Z113) and the National Science Foundation of China (Nos. 51471025, 51671020, and 51210105006), 111 Project (B07003), and the Program for Changjiang Scholars and the Innovative Research Team of the University. P.K. Liaw very much appreciates the financial support from the US National Science Foundation (DMR-1611180) with D. Farkas as the contract monitor. P.K. Liaw is very grateful for the support from the U.S. Department of Energy, Office of Fossil Energy, National Energy Technology Laboratory (NETL) (DE-FE-0008855, DE-FE-0011194, and DE-FE-0024054), and the US Army Research Office (W911NF-13-1-0438) with V. Cedro, J. Mullen, S. Markovich, R. Dunst, S. Mathaudhu, D. Stepp, and M. P. Bakas as contract monitors. M.C. Gao and J.A. Hawk acknowledge financial support by the Cross-Cutting Technologies Program at the NETL-Strategic Center for Coal, managed by Robert Romanosky (Technology Manager) and Charles Miller (Technology Monitor). The computing portion of the research was executed through the NETL's Office of Research and Development's Innovative Process Technologies (IPT) Field Work Proposal. The research performed by the AECOM Staff was conducted under the RES contract DE-FE-0004000. M.C. Gao wishes to thank Chao Jiang for sharing the SQS structures, and Mike Widom, and David Alman for discussions on the HEA topic. L. Ouyang thanks the financial support from NETL (DE-FE-0011549). Y.Q. Cheng is supported by the Scientific User Facilities Division, Office of Basic Energy Sciences, U.S. Department of Energy. Computational resources were made available through the Center of Nanophase Materials Sciences, Oak Ridge National Laboratory.
| Funders | Funder number |
|---|---|
| Cross-Cutting Technologies Program | DE-FE-0011549, DE-FE-0004000 |
| National High Technology Research and Development Program of China | 2009AA03Z113 |
| Office of Basic Energy Sciences | |
| Program for Changjiang Scholars | |
| Scientific User Facilities Division | |
| US Army Research Office | W911NF-13-1-0438 |
| US National Science Foundation | DMR-1611180 |
| U.S. Department of Energy | |
| Office of Fossil Energy | |
| Oak Ridge National Laboratory | |
| National Energy Technology Laboratory | DE-FE-0024054, DE-FE-0011194, DE-FE-0008855 |
| National Energy Technology Laboratory | |
| National Natural Science Foundation of China | 51210105006, 51471025, 51671020 |
| National Natural Science Foundation of China | |
| Higher Education Discipline Innovation Project | B07003 |
| Higher Education Discipline Innovation Project |
Keywords
- AIMD simulation
- DFT calculation
- High entropy alloy
- Magnetic behavior
- Phase formation