Bulk and Defect Properties of Ordered Intermetallics: A First-Principles Total-Energy Investigation

Abstract

First-principles quantum mechanical calculations based on local-density-functional theory have been used to investigate the fundamental factors that govern the deformation and fracture behavior of ordered intermetallic alloys. Unlike in Ni3Al, the calculated elastic constants and shear fault energies indicate that anomalous yield strength behavior is not likely to occur in Ni3Si. From the calculated Griffith strength and a phenomenological theory relating fracture toughness to ideal cleavage strength, Ni3Si is predicted to be ductile with respect to cleavage fracture. For TiAl, we find the absence of structural vacancies due to the strong Ti-Al bonding and similar atomic radii for Ti and Al. For NiAl, the defect structure is found to be dominated by two types of defects - monovacancies on the Ni sites and substitutional antisite defects on the Al sites. For FeAl, on the other hand, we find a more complex defect structure, which is closely related to the importance of electronic structure effect in FeAl. More importantly, we predict the strong tendency for vacancy clustering in FeAl due to the large binding energy found for divacancies. Effects of thermomechanical history on microhardness are discussed in terms of the calculated results.

This is a preview of subscription content, access via your institution.

References

  1. 1.

    P. Hohenberg and W. Kohn, Phys. Rev. B 126, 864 (1964).

    Article  Google Scholar 

  2. 2.

    E. Wimmer, H, Krakauer, M. Weinert, and A. J. Freeman, Phys. Rev. B 24, 864 (1981).

    CAS  Article  Google Scholar 

  3. 3.

    S. G. Louie, K. M. Ho, and M. L. Cohen, Phys. Rev. B 19, 1774 (1979).

    CAS  Article  Google Scholar 

  4. 4.

    K. M. Ho, C. L. Fu, and B. N. Harmon, Phys. Rev. B 22, 1575 (1984).

    Article  Google Scholar 

  5. 5.

    P. A. Flinn, Trans, AIME 218, 145 (1960).

    CAS  Google Scholar 

  6. 6.

    M. H. Yoo, Scripta Met. 20, 915 (1986).

    CAS  Article  Google Scholar 

  7. 7.

    The results presented here for Ni3Al are better converged results as compared to those reported before (e.g., see C. L. Fu, International Symposium on Intermetallics Compounds - Structure and Mechanical Properties, edited by O. Izumi, (Sendai, The Japan Institute of Metals);. p. 387).

  8. 8.

    K. J. Hemker, B. Viguer, R. Schanblin, and M. J. Mills, in this proceedings.

  9. 9.

    R. Lowrie, Trans. AIME 194, 1093 (1952).

    Google Scholar 

  10. 10.

    T. Suzuki, Y. Oya, and S. Ochiai, Metall. Trans. 15A, 173 (1984).

    CAS  Article  Google Scholar 

  11. 11.

    T. Takasugi and M. Yoshida, Phil. Mag. A 65, 613 (1992).

    CAS  Article  Google Scholar 

  12. 12.

    H. Yasuda, T. Takasugi, and M. Koiwa, Acta Met. 40, 381 (1992).

    CAS  Article  Google Scholar 

  13. 13.

    W. W. Gerberich, H. Huang, and P. G. Marsh, NASA Conf. on Advanced Earth-to-Orbit Propulsion Technology, Marshall Space Flight Center, Huntsville, Alabama, May 1992.

    Google Scholar 

  14. 14.

    M. H. Yoo and C. L. Fu, Mater. Sci. and Eng. A153, 470 (1992).

    CAS  Article  Google Scholar 

  15. 15.

    For example, see A. G. Fox and M. A. Tabbernor, Acta Metall. 39, 669 (1991).

    CAS  Article  Google Scholar 

  16. 16.

    C. L. Fu and M. H. Yoo, Phil. Mag. Lett. 62, 159 (1990).

    CAS  Article  Google Scholar 

  17. 17.

    H. A. Lipsitt, D. Schechtman, and R. E. Schafrik, Metall. Trans. A6, 1991 (1975).

    Article  Google Scholar 

  18. 18.

    R. E. Schafrik, Metall. Trans A 8, 1003 (1977).

    Article  Google Scholar 

  19. 19.

    H. Deve and A. G. Evans, Acta Metall. 39, 1171 (1991).

    CAS  Article  Google Scholar 

  20. 20.

    C. L. Fu and M. H. Yoo, Intermetallics, to be published.

  21. 21.

    Y. Shirai and M. Yamaguchi, Mater. Sci. and Eng. A 152, 173 (1992).

    Article  Google Scholar 

  22. 22.

    C. L. Fu and M. H. Yoo, Acta Metall. 40, 703 (1992).

    CAS  Article  Google Scholar 

  23. 23.

    M. H. Yoo and C. L. Fu, Scripta Metall. 25, 2345 (1991).

    CAS  Article  Google Scholar 

  24. 24.

    C. T. Liu, E. H. Lee, and C. G. McKamey, Scripta Metall. 23, 875 (1989).

    CAS  Article  Google Scholar 

  25. 25.

    C. L. Fu and G. S. Painter, J. Mater. Res. 6, 719 (1991).

    CAS  Article  Google Scholar 

  26. 26.

    P. Nagpal and I. Baker, Metall. Trans. 21A, 2281 (1990).

    CAS  Article  Google Scholar 

  27. 27.

    C. L. Fu, Y. Y. Ye, and M. H. Yoo, to be published.

  28. 28.

    For example, see J. P. Neumann, Y. A. Chang, and C. M. Lee, Acta Metall. 24, 593 (1976); and references therein.

    CAS  Article  Google Scholar 

Download references

Acknowledgement

Research sponsored by the Division of Materials Science, Office of Basic Energy Sciences, U.S. Department of Energy under contract DE-AC05-84OR21400 with Martin Marietta Energy Systems, Inc.

Author information

Affiliations

Authors

Corresponding author

Correspondence to Y.-Y. Ye.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Fu, C.L., Ye, YY. & Yoo, M.H. Bulk and Defect Properties of Ordered Intermetallics: A First-Principles Total-Energy Investigation. MRS Online Proceedings Library 288, 21–32 (1992). https://doi.org/10.1557/PROC-288-21

Download citation