Hostname: page-component-586b7cd67f-r5fsc Total loading time: 0 Render date: 2024-11-25T15:31:55.105Z Has data issue: false hasContentIssue false

CVM-based first-principles calculations for Fe-based alloys

Published online by Cambridge University Press:  27 September 2011

Tetsuo Mohri*
Affiliation:
Division of Materials Science and Engineering, Faculty of Engineering and Research Center for Integrative Mathematics, Hokkaido University, Sapporo 060-8628, JAPAN
Get access

Abstract

Cluster Variation Method (CVM) has been recognized as one of the most reliable theoretical tools to incorporate wide range of atomic correlations into a free energy formula. By combining CVM with electronic structure total energy calculations, one can perform first-principles calculations of alloy phase equilibria. The author attempted such CVM-based first-principles calculations for various alloy systems including noble metal alloys, transition-noble alloys, III-V semiconductor alloys and Fe-based alloy systems. Furthermore, CVM can be extended to two kinds of kinetics calculations. One is Path Probability Method (PPM) which is the natural extension of the CVM to time domain and is quite powerful to investigate atomistic kinetic phenomena. The other one is Phase Field Method (PFM) with the CVM free energy as a homogeneous free energy density term in the PFM. The author’s group applied the latter procedure to study time evolution process of ordered domains associated with disorder-L10 transition in Fe-Pd and Fe-Pt systems. CVM has, therefore, a potential applicability for the systematic studies covering atomistic to microstructural scales. It has been, however, pointed out that the conventional CVM is not able to include local lattice relaxation effects and that the resulting order-disorder transition temperatures are overestimated. In order to circumvent such inconveniences, Continuous Displacement Cluster Variation Method (CDCVM) has been developed. Since first-principles CDCVM calculations are still beyond the scope at the present stage, preliminary results on the two dimensional square lattice and an fcc lattice with primitive Lennard-Jones type potentials are demonstrated in the last section.

Type
Research Article
Copyright
Copyright © Materials Research Society 2011

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

REFERENCES

1. for instance, Tetsuo Mohri: Alloy Physics, Chapt. 10 and references therein, ed. Pfeiler, W., WILEY-VCH, 525 (2007).Google Scholar
2. Kikuchi, R.: Phys. Rev., Vol. 81, 998 (1951).Google Scholar
3. Chen, L.-Q.: Ann. Rev. Mat. Res., Vol. 32, 113 (2002)., and references therein.Google Scholar
4. Cahn, J. W. and Hilliard, J.E.: J. Chem. Phys., Vol. 28, 258 (1958).Google Scholar
5. Fan, D. and Chen, L.-Q.: Acta mater., Vol. 45, 3297 (1997).Google Scholar
6. Ohno, M.: Ph.D dissertation, Grad. School of Engr., Hokkaido Univ., 2004.Google Scholar
7. Mohri, T., Ohno, M. and Chen, Y.: J. Phase Equil. and Diffusion, Vol. 27, 47 (2006).Google Scholar
8. Mohri, T., Terakura, K., Oguchi, T. and Watanabe, K.: Phase Transformation ‘87, ed. Lorimer, G. W., The Institute of Metals, 433 (1988).Google Scholar
9. Kikuchi, R.: J. Phase. Equilibria, Vol. 19, 412 (1998).Google Scholar
10. Kikuchi, R. and Masuda-Jindo, K.: Comp. Mat. Sci., Vol. 14, 295 (1999).Google Scholar
11. Mohri, T.: International J.of Materials Research (formerly Zeitschrift Metallkunde), in press.Google Scholar
12. Mohri, T.: Materials Trans., Vol. 49, 2515 (2008).Google Scholar
13. Connolly, J.W. and Williams, A.R.: Phys. Rev., Vol. B27, 5169 (1983).Google Scholar
14. Kikuchi, R.: J. Chem. Phys., Vol. 60, 1071 (1974).Google Scholar
15. Finel, A. and Tetot, R.: in Stability of Materials (ed. By Gonis, A., Turchi, P.E.A. and Kudrnovsky, J., Plenum Press, New York, 1996), p.197.Google Scholar
16. Mohri, T. and Chen, Y.: Mat. Trans., Vol. 45, 1478 (2004).Google Scholar
17. Mohri, T. and Chen, Y.: J. Alloys and Compounds, Vol. 383, 23 (2004).Google Scholar
18. Mohri, T. and Chen, Y.: Mat. Trans., Vol. 43, 2104 (2002).Google Scholar
19. Morruzi, V., Janak, J.F. and Schwarz, K.: Phys. Rev., Vol. B37, 790 (1988).Google Scholar
20. Becker, J.D., Sanchez, J.M. and Tien, J.K., Mater. Res. Soc. Symp. Proc. 213, 113 (1991).Google Scholar
21. Mohri, Tetsuo, Morita, Tomohiko, Kiyokane, Naoya and Ishii, Hiroaki: Journal of Phase Equilibria and Diffusion, Vol. 30, 553 (2009).Google Scholar
22. Kikuchi, R., Prog. Theor. Phys. Suppl. 35, 1(1966).Google Scholar
23. Ohno, Munekazu and Mohri, Tetsuo, Materials Trans. 47, 2718 (2006).Google Scholar