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Quantitative Predictions from Solid-State Physics - What do Phase Diagram Calculators Want?

Published online by Cambridge University Press:  15 February 2011

Malcolm Rand
Malcolm Rand*
Affiliation:
AERE, Harwell, Didcot, Oxon, UK
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Abstract

The types of information required for the calculation of phase diagrams are discussed by considering the computation of typical ternary sections from the constituent binary systems. Such calculations require a knowledge of the Gibbs energy of transformation (lattice stabilities) and Gibbs energies of mixing of wholly metastable, as well as the stable phases in binary systems. Similarly, the stabilities of metastable compounds such as Fe7C3 would be required for computations in the C-Cr-Fe system.

These requirements are compared to the information provided by solid-state theoreticians. Essentially such calculations provide enthalpy values at 0 K (or some unspecified temperature for semi-empirical models); however the lattice dynamics and configurational entropy of simple phases have been included in some recent computations. The importance of predicting the entropy and thus heat capacity of metallic phases - particularly metastable phases - is therefore emphasized. Identification of those contributions to the heat capacity which are responsible for the differences between metal polymorphs is discussed, particularly the formalism for magnetic and atomic ordering phenomena. Predictions of ordering temperatures and magnetic moments as a function of composition would be of considerable help for phase diagram calculations.

Ab-initio calculations already have considerable success in predicting molar volumes of both stable and metastable phases, so that such information will undoubtedly be of considerable value in studying alloy behaviour at high pressures.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 19: Symposium E – Alloy Phase Diagrams , 1982 , 81
Copyright
Copyright © Materials Research Society 1983

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References

REFERENCES

1. Kaufman, L. and Bernstein, H., Computer Calculations of Phase Diagrams, (Academic Press, New York 1970).Google Scholar
2. Hillert, M., Calphad 4, 1 (1980).CrossRefGoogle Scholar
3. Lukas, H.L., Henig, E-Th., Zimmerman, B., Calphad 1, 225 (1977).CrossRefGoogle Scholar
4. Sundman, B., Report D28, Div. of Physical Metallurgy, Royal Inst. of Technology, Stockholm (1981).Google Scholar
5. Lin, P.L., Bale, C.W. and Pelton, A.D., Proc. Symp. Calculation of Phase Diagrams and Thermochemistry of Alloy Phases, Warrendale Pa. (USA),Google Scholar
5aMet. Soc. AIME (1981), pp. 26–45.Google Scholar
6. Miedema, A.R., De Châtel, P.F. and de Boer, F.R., Physica 100B, 1 (1980).Google Scholar
7. Machlin, E.S., Calphad 5, 1 (1981).CrossRefGoogle Scholar
8. Machlin, E.S. and Gee, Pak. T., J. Solid State Chem. 24, 277 (1978).CrossRefGoogle Scholar
9. Pettifor, D.G., Phys. Rev. Letters 42, 846 (1979).CrossRefGoogle Scholar
10. Bennett, L.H. and Watson, R.E., Calphad 5, 19 (1981); ib 5, 25 (1981).CrossRefGoogle Scholar
11. Brewer, L., Science 161, 115 (1968).CrossRefGoogle Scholar
12. Brewer, L., Molybdenum - Physico-Chemical Properties of its Compounds and Alloys, Atomic Energy Review, Special Issue No. 7, IAEA Vienna (1980).Google Scholar
13. de Fontaine, D., Physica 103B 57 (1981).Google Scholar
14. Kikuchi, R., Physica 103B, 41 (1981).Google Scholar
15. Williams, A.L., Gelatt, C.D. and Moruzzi, V.L., Phys. Rev. Letters 44, (1980), 429.CrossRefGoogle Scholar
16. Yin, M.T. and Cohen, M.L., Phys. Rev. Letters 45, 1004 (1980).CrossRefGoogle Scholar
17. Yin, M.T. and Cohen, M.L., Solid State Commun. 38, 625 (1981).CrossRefGoogle Scholar
18. McMahan, A.K., Yin, M.J. and Cohen, M.L., Phys. Rev. 24B, 7210 (1981).CrossRefGoogle Scholar
19. Yin, M.T. and Cohen, M.L., Phys. Rev. 26B, 3259, 1982.CrossRefGoogle Scholar
20. Hafner, J., Phys. Rev. 21B, 406 (1980).CrossRefGoogle Scholar
21. JANAF Thermochemical Tables NSRDS-NBS-37 (1970).Google Scholar
22. Grimvall, G., Physica Scripta 11, 381 (1975).CrossRefGoogle Scholar
23. Grimvall, G. and Ebbsjo, I., Physica Scripta 12, 168 (1975).CrossRefGoogle Scholar
24. Grimvall, G., Physica Scripta 12, 168 (1975).CrossRefGoogle Scholar
25. Miodownik, A.P., Calphad 1, 133 (1977).CrossRefGoogle Scholar
26. Miodownik, A.P. and Hillert, M., Calphad 4, 143 (1980).CrossRefGoogle Scholar
27. Inden, G., Physica 103B, 82 (1981).Google Scholar
28. Hillert, M. and Jarl, M., Calphad 2, 227 (1978).CrossRefGoogle Scholar
29. Froyen, S. and Cohen, M.L., Phys. Rev. 43, 447 (1982).Google Scholar