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Atomic structures of nonequilibrium alloys in an immiscible Co–Ag system

Published online by Cambridge University Press:  03 March 2011

H.B. Guo  and
B.X. Liu
H.B. Guo
Affiliation:
Advanced Materials Laboratory, Department of Materials Science and Engineering,Tsinghua University, Beijing 100084, People’s Republic of China
B.X. Liu*
Affiliation:
Advanced Materials Laboratory, Department of Materials Science and Engineering,Tsinghua University, Beijing 100084, People’s Republic of China
*
a)Address all correspondence to this author.e-mail: dmslbx@tsinghua.edu.cn
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Abstract

A Co–Ag potential in the form of TB-SMA (the second moment approximation of the tight-binding scheme) is derived based on some ab initio calculated physical properties. Applying the derived potential, molecular dynamics simulations reveal that a Co-/Ag-based solid solution retains its atomic homogeneity up to a critical ratio of9 Ag/12 Co at.%, over which the Ag/Co solute atoms begin to segregate. Correspondingly, a cage-like configuration is proposed to have 1 Ag/Co atom isotropically surrounded by 9 Co/7 Ag atoms for the homogeneous solid solution. Moreover, when the solute atoms exceed 12 Ag/18 Co at.%, the solid solution turns into an amorphous phase with inhomogeneous atomic structure.

Keywords

Computer simulationPhase transformation
Type
Articles
Information
Journal of Materials Research , Volume 19 , Issue 5 , May 2004 , pp. 1364 - 1368
Copyright
Copyright © Materials Research Society 2004

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