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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: [email protected]
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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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References

REFERENCES

1Nonequilibrium Processing of Materials, edited by Suryanarayana, C. (Elsevier Science, Amsterdam, The Netherlands, 1999).Google Scholar
2deBoer, F.R., Boom, R., Mattens, W.C. M., Miedema, A.R. and Niessen, A.K., Cohesion in Metals: Transition Metal Alloys (North-Holland, Amsterdam, The Netherlands, 1989).Google Scholar
3Liu, B.X., Lai, W.S. and Zhang, Q., Irradiation induced amorphization in metallic multilayers and calculation of glass-forming ability from atomistic potential in the binary metal systems. Mater. Sci. Eng.: Reports 29, 1 (2000).Google Scholar
4Liu, B.X., Lai, W.S. and Zhang, Z.J., Solid-state crystal-to-amorphous transition in metal-metal multilayers and its thermodynamic and atomistic modeling. Adv. Phys. 50, 367 (2001).CrossRefGoogle Scholar
5He, J.H., Sheng, H.W., Schilling, P.J., Chien, C-L. and Ma, E., Amorphous structures in the immiscible Ag-Ni system. Phys. Rev. Lett. 86, 2826 (2001).CrossRefGoogle ScholarPubMed
6Gong, H.R., Kong, L.T., Lai, W.S. and Liu, B.X., Atomistic modeling of solid-state amorphization in an immiscible Cu-Ta system. Phys. Rev. B 66, 104204 (2002).CrossRefGoogle Scholar
7Tsang, C., Fontana, R.E.Jr., Lin, T., Heim, D.E., Speriosu, V.S., Gurney, B.A. and Williams, M.L., Design, fabrication and testing of spin-valve read heads for high-density recording. IEEE Trans. Magn. 30, 3801 (1994).CrossRefGoogle Scholar
8Ducastelle, F. in Computer Simulation in Materials Science, edited by Meyer, M. and Pontikis, V. (NATO Advanced Study Institute, Series E, 205,Kluwer, Dordrecht, The Netherlands, 1991).Google Scholar
9Chadi, D.J., Surface atomic structures of covalent and ionic semiconductors. Phys. Rev. B 19,2074 (1979).CrossRefGoogle Scholar
10Cleri, F. and Rosato, V., Tight-binding potentials for transition metals and alloys. Phys. Rev. B 48, 22 (1993).CrossRefGoogle ScholarPubMed
11Kresse, G. and Hafner, J., Ab initio molecular dynamics for liquid metals. Phys. Rev. B 47, 558 (1993).Google Scholar
12Liu, J.B. and Liu, B.X., Irradiation and interface induced formation of a nonequilibrium Ag3Co phase predicted by ab initio calculation. Phys. Rev. B 64, 4102 (2001).Google Scholar
13Parrinello, M. and Rahman, A., Polymorphic transitions in single crystals: A new molecular dynamics method. J. Appl. Phys. 52, 7182 (1981).Google Scholar
14Phillpot, S.R., Yip, S. and Wolf, D., Anomalous temperature behavior of Sn impurities. Comput. Phys. 3, 20 (1989).CrossRefGoogle Scholar
15Ebels, U., Stamps, R.L., Zhou, L., Wigen, P.E., Ounadjela, K., Greggs, J., Morkowski, J. and Szajek, A., Induced phase shift in interlayer magnetic exchange coupling: Magnetic layer doping. Phys. Rev. B 58, 6367 (1998).CrossRefGoogle Scholar
16Morkowski, J.A. and Szajek, A., Electronic band structure and calculated photoemission spectra of USi3 compound. Acta Physica Polonica A 98, 5 (2000).Google Scholar
17Gester, M., Matthew, J.A.D., Thompson, S.M. and Beamson, G., Electron spectroscopic evidence of metastable alloy formation of Ag and Au in Co. Phys. Rev. B 59, 15654 (1999).CrossRefGoogle Scholar