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Phase Diagram Features Associated with Multicritical Points in Alloy Systems

Published online by Cambridge University Press:  15 February 2011

Samuel M. Allen  and
John W. Cahn
Samuel M. Allen
Affiliation:
Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
John W. Cahn
Affiliation:
Center for Materials Science, National Bureau of Standards, Washington, D.C. 20234
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Abstract

Many features in the vicinity of critical points in phase diagrams can be illustrated using a Landau type free energy expansion as a power series in one or more order parameters and composition. This simple approach can be used with any solution model. It also predicts limits to metastability, and is useful for understanding mechanisms of phase change. The theory is applied to all the critical points that can occur in binary systems according to a Landau theory: critical consolute points, order-disorder transitions, tricritical points, critical end points, as well as to systems in which two transitions such as chemical and magnetic ordering occur.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 19: Symposium E – Alloy Phase Diagrams , 1982 , 195
Copyright
Copyright © Materials Research Society 1983

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References

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