Magnetic BiMn-α phase synthesis prediction: First-principles calculation, thermodynamic modeling and nonequilibrium chemical partitioning

Journal Article · Fri Apr 29 00:00:00 EDT 2016 · Computational Materials Science

DOI:https://doi.org/10.1016/j.commatsci.2016.04.016· OSTI ID:1254316

Zhou, S. H. ^[1]; Liu, C. ^[2]; Yao, Y. X. ^[3]; Du, Y. ^[4]; Zhang, L. J. ^[4]; Wang, C. -Z. ^[3]; Ho, K. -M. ^[3]; Kramer, M. J. ^[3]

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1. Ames Lab., Ames, IA (United States)
2. Iowa State Univ., Ames, IA (United States)
3. Ames Lab. and Iowa State Univ., Ames, IA (United States)
4. Central South Univ., Hunan (People's Republic of China)

BiMn-α is promising permanent magnet. Due to its peritectic formation feature, there is a synthetic challenge to produce single BiMn-α phase. The objective of this study is to assess driving force for crystalline phase pathways under far-from-equilibrium conditions. First-principles calculations with Hubbard U correction are performed to provide a robust description of the thermodynamic behavior. The energetics associated with various degrees of the chemical partitioning are quantified to predict temperature, magnetic field, and time dependence of the phase selection. By assessing the phase transformation under the influence of the chemical partitioning, temperatures, and cooling rate from our calculations, we suggest that it is possible to synthesize the magnetic BiMn-α compound in a congruent manner by rapid solidification. The external magnetic field enhances the stability of the BiMn-α phase. In conclusion, the compositions of the initial compounds from these highly driven liquids can be far from equilibrium.

• Research Organization: Ames Lab., Ames, IA (United States)
• Sponsoring Organization: USDOE Advanced Research Projects Agency - Energy (ARPA-E); USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: AC02-07CH11358; 11/CJ000/09/03
• OSTI ID: 1254316
• Alternate ID(s): OSTI ID: 1341115
• Report Number(s): IS-J-8977; PII: S0927025616301756
• Journal Information: Computational Materials Science, Vol. 120, Issue C; ISSN 0927-0256
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
first-principles calculation
Hubbard U correction
chemical partitioning
hard magnetic MnBi
composition far from equilibrium