Computation of entropies and phase equilibria in refractory V-Nb-Mo-Ta-W high-entropy alloys

Journal Article · Mon Jan 01 00:00:00 EST 2018 · Acta Materialia

DOI:https://doi.org/10.1016/j.actamat.2017.10.017· OSTI ID:1462027

Wang, Yi ^[1]; Yan, Ming  ^[2]; Zhu, Qiang ^[3]; Wang, Williams Yi ^[4]; Wu, Yidong ^[5]; Hui, Xidong ^[5]; Otis, Richard  ^[6]; Shang, Shun-Li ^[1]; Liu, Zi-Kui ^[1]; Chen, Long-Qing ^[1]

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1. The Pennsylvania State University, University Park, PA (United States). Department of Materials Science and Engineering
2. Southern University of Science and Technology, Shenzhen, Guangdong (China). Department of Materials Science and Engineering and Shenzhen Key Laboratory for Additive Manufacturing of High-performance Materials
3. South University of Science and Technology, Shenzhen, Guangdong (China). Department of Mechanical and Energy Engineering
4. Northwestern Polytechnical University, Xi'an, Shaanxi (China). State Key Laboratory of Solidification Processing
5. University of Science and Technology Beijing, Beijing (China). State Key Laboratory for Advanced Metals and Materials
6. The Pennsylvania State University, University Park, PA (United States). Department of Materials Science and Engineering; California Institute of Technology, Pasadena, CA (United States). Engineering and Science Directorate, Jet Propulsion Laboratory

We have applied the first-principles phonon method to the refractory V-Nb-Mo-Ta-W high-entropy al-loys (HEAs) to predict the major phase separations in the temperature-compositional space and hence the associated entropy changes within the systems, taking into account vibrational, electronic, and configurational contributions to the total entropy. The first-principles calculations covered 178 phases ranging from pure elements, the ordered B2, B32, B23,B22, hR8, hR7, tI6, C15, and D0₃ binary phases, two ordered MoNbTaW quaternary phases, and the partially disordered and completely disordered bcc phases. By sorting their relative phase stabilities with the Dantzig's simplex mini mization algorithm, the possibilities of phase separation for the refractory quaternary and quinary HEAs were thermodynamically found in the temperature range of 500e907 K.

• Research Organization: Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). National Energy Research Scientific Computing Center (NERSC)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22). Materials Sciences & Engineering Division; USDOE Office of Science (SC), Advanced Scientific Computing Research (ASCR)
• DOE Contract Number: FG02-07ER46417; AC02-05CH11231
• OSTI ID: 1462027
• Journal Information: Acta Materialia, Vol. 143, Issue C; ISSN 1359-6454
• Publisher: Elsevier
• Country of Publication: United States
• Language: English