Hostname: page-component-78c5997874-4rdpn Total loading time: 0 Render date: 2024-11-10T09:00:35.502Z Has data issue: false hasContentIssue false
  • English
  • Français

First-Principles Study of Phase Stability in Pd-Rh Alloys

Published online by Cambridge University Press:  28 February 2011

D.D. Johnson ,
P.E.A. Turchi ,
Marcel Sluiter ,
D.M. Nicholson ,
F.J. Pinski  and
G.M. Stocks
D.D. Johnson
Affiliation:
Sandia National Laboratories, Livermore, CA 94550
P.E.A. Turchi
Affiliation:
Lawrence Livermore National Laboratory, Livermore, CA 94551
Marcel Sluiter
Affiliation:
Lawrence Livermore National Laboratory, Livermore, CA 94551
D.M. Nicholson
Affiliation:
Oak Ridge National Laboratory, Oak Ridge, TN 37831
F.J. Pinski
Affiliation:
University of Cincinnati, Cincinnati, OH 45221
G.M. Stocks
Affiliation:
Oak Ridge National Laboratory, Oak Ridge, TN 37831
Get access

Abstract

We present a study of the mixing energies and the effective cluster interactions which form the configurational part of the internal energy of Pd-Rh substitutional alloys. We discuss the tendency towards phase-separation and more generally phase stability. The effects of a substitutional ternary addition on the tendencies toward order or phase-separation are also reported. The Korringa-Kohn-Rostoker Coherent-Potential Approximation (KKR-CPA) is used to investigate the electronic structure effects and energetics of the random alloy. Moreover, we use the Generalized Perturbation Method (GPM), using the KKR-CPA random alloy as a reference medium, to investigate the effective interactions which determine phase stability. We briefly comment on other factors which may give important contributions to the total free-energy of the alloy. We also contrast the GPM with the Connolly-Williams approach for calculating phase diagrams from first-principles. Finally, we explore the inadequacies of the frozen-potential and Harris approximations to the energetics of alloying.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 186: Symposium I – Alloy Phase Stability and Design , 1990 , 21
Copyright
Copyright © Materials Research Society 1991

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Györffy, B.L. and Stocks, G.M., Phys. Rev. Lett. 50, 374, (1983).Google Scholar
2. Connolly, J.W.D. and Williams, A.R., Phys. Rev. B 27, 5169, (1983).Google Scholar
3. Ducastelle, F. and Gautier, F., J. Phys. F 6, 2039, (1976).Google Scholar
4. Johnson, D.D., Nicholson, D.M., Pinski, F.J., Stocks, G.M., and Györffy, B.L., Phys. Rev. Lett. 56, 2088 (1986); and, to be published in, 15 May, Phys. Rev. B (1990).Google Scholar
5. Turchi, P.E.A., Stocks, G.M., Butler, W.H., Nicholson, D.M., and Gonis, A., Phys. Rev. B 37, 5982, (1988).Google Scholar
6. Pettifor, D.G., J. Chem. Phys. 69, 2930, (1978).Google Scholar
7. Harris, J., Phys. Rev. B 31, 1770, (1985).Google Scholar
8. Polatoglou, H.M. and Methfessel, M., Phys. Rev. B 37, 10403, (1988).Google Scholar
9. Zaremba, E., J. Phys.: Cond. Matter 2, 2479, (1990).Google Scholar
10. See, e.g., Turchi, P.E.A., Sluiter, M., and Fontaine, D. de, Phys. Rev. B 36, 3161, (1987).Google Scholar
11. Shield, J.E. and Williams, R.K., Scripta Met. 21, 1475, (1987).Google Scholar
12. Sluiter, M., Turchi, P.E.A., Johnson, D.D., Pinski, F.J., Nicholson, D.M., Stocks, G.M., to be in the Fall 1989 MRS proceedings, eds. Shapiro, S.M., Moss, S.C., Jorgensen, J.D..Google Scholar
13. Myles, K.M., AIME Trans. 242, 1523, (1968).Google Scholar
14. Staunton, J.B., Johnson, D.D., and Pinski, F.J., submitted to Phys. Rev. Lett.Google Scholar