Skip to main content Accessibility help
×
Home

B2 Phases and their Defect Structures: Part I.I. Ab initio Vibrational and Electronic Free Energy in the Al-Ni-Pt-Ru System

  • Raymundo Arroyave (a1), Sara Prins (a1) (a2) and Zi-Kui Liu (a1)

Abstract

In this work, we calculate the finite temperature thermodynamic properties of the binary B2 phases in the Al-Ni-Pt-Ru system, particularly the B2 RuAl phase in the Pt-Al-Ru ternary, through the incorporation of the vibrational and electronic contributions to the total free energy. The harmonic approximation is used to consider the atomic vibrations, with the quasi-harmonic correction to account for volume expansion effects on the vibrational entropy as the temperature increases. The vibrational entropy calculations are incorporated through the supercell approach. The calculated phonon dispersion curves show that the B2 PtRu structure is mechanically unstable at low temperatures, while B2 PtAl is marginally stable. The thermal electronic contribution is added to the total free energy. Finally, the formation enthalpies and entropies of B2 RuAl are calculated as a function of temperature.

Copyright

References

Hide All
1. Chen, M. W., Ott, R. T., Hufnagel, T. C., Wrigth, P. K. and Hemker, K. J., Surf. Coat. Technol. 163–164 (2003) 25.
2. Tolypgo, V. K. and Clarke, D. R., Acta Mater. 48 (2000) 3283.
3. Tryon, B., Pollock, T. M., Gigliotti, M. F. X. and Hemker, K. J., Scripta Materialia 50 (2004) 845.
4. Saunders, N. and Miodownik, A. P., CALPHAD (Calculation of Phase Diagrams): A Comprehensive Guide (Pergamon, Oxford; New York, 1998).
5. Gonze, X., Phys. Rev. B 55 (1997) 10337.
6. Wei, S. and Chou, M. Y., Phys. Rev. Lett. 69 (1992) 2799.
7. van de Walle, A. and Ceder, G., Rev. Mod. Phys. 74 (2002) 11.
8. Kohn, W. and Sham, L. J., Phys. Rev. 140 (1965) A1133.
9. Kresse, G.. (2004), vol. 2004.
10. van de Walle, A., Asta, M. and Ceder, G., CALPHAD 26 (2002) 539.
11. Dutton, D. H., Brockhousse, B. N. and Miiller, A. P., Can. J. Phys. 50 (1972) 2915.
12. Dederichs, P. H., Schober, H. and Sellmyer, D. J., in Metals: Phonon States, Electron States and Fermi Surfaces Hellwege, K. H., Olsen, J. L., Eds. (Springer-Verlag, Berlin, 1981), vol. 13a, Pt. 7.
13. Smith, H. G. and Wakabayashi, N., Solid State Commun. 39 (1981) 371.
14. Antonov, V. N., Milman, V. Y., Nemoshkalenko, V. V. and Zhalko-Titarenko, A. V., Z. Phys. B. 79 (1990) 223.
15. Villars, P.. (2004), vol. 2004.
16. Huang, X., Bungaro, C., Godlevsky, V. and Rabe, K. M., Phys. Rev. B 65 (2001) 141081.
17. McAlister, A. J. and Kahan, D. J., Bull. Alloy Phase Diagrams 7 (1986) 47.
18. Swift, D. C., Ackland, G. J., Hauer, A. and Kyrala, G. A., Phys. Rev. B 64 (2001) 2141071.
19. Knacke, O., Kubaschewski, O. and Hesselmann, K., Thermochemical Properties of Inorganic Substances (Springer-Verlag, New York, ed. Second Edition, 1991), vol. I.
20. Wang, Y., Liu, Z.-K. and Chen, L.-Q., Acta Mater. 52 (2004) 2665.

Related content

Powered by UNSILO

B2 Phases and their Defect Structures: Part I.I. Ab initio Vibrational and Electronic Free Energy in the Al-Ni-Pt-Ru System

  • Raymundo Arroyave (a1), Sara Prins (a1) (a2) and Zi-Kui Liu (a1)

Metrics

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed.