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Thermodynamics and liquid phase separation in the Cu–Co–Nb ternary alloys

Published online by Cambridge University Press:  31 January 2011

Cuiping Wang*
Affiliation:
Department of Materials Science and Engineering, College of Materials, and Research Center of Materials Design and Application, Xiamen University, Xiamen 361005, People’s Republic of China
Kiyohito Ishida
Affiliation:
Department of Materials Science, Graduate School of Engineering, Tohoku University, Sendai 980-8579, Japan
*
a)Address all correspondence to this author. e-mail: [email protected]
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Abstract

This work first deals with the effect of Nb addition on the liquid phase separation in the Cu–Co system, which displays a metastable liquid miscibility gap. The isothermal sections at 800, 900, 1000, 1100, and 1200 °C in the Cu–Co–Nb system have been experimentally determined by optical microscopy, electron probe microanalysis, and x-ray diffraction on the equilibrated alloys, and the phase equilibria in the Cu–Co–Nb ternary system were thermodynamically assessed by using CALPHAD (Calculation of Phase Diagrams) method on the basis of the presently determined experimental data. Nb additions can stabilize the metastable liquid phase separation in the Cu–Co binary system and significantly increase its critical temperature. The solidified Cu–Co–Nb alloys appearing on the top-bottom separated microstructural morphology under low cooling rate while forming core-type macrostructural morphology under high cooling rate have been confirmed.

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Articles
Copyright
Copyright © Materials Research Society 2010

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References

REFERENCES

1.Nakagawa, Y.Liquid immiscibility in copper-iron and copper-cobalt systems in the supercooled state. Acta Metall. 6, (11)704 (1958)CrossRefGoogle Scholar
2.Yamauchi, I., Ueno, N., Shimaoka, M., Ohnaka, I.Undercooling in Co–Cu alloys and its effect on solidification structure. J. Mater. Sci. 33, 371 (1998)CrossRefGoogle Scholar
3.Kolbe, M., Cao, C.D., Lu, X.Y., Galenko, P.K., Wei, B., Herlach, D.M.Solidification behavior of undercooled Co–Cu alloys showing a metastable miscibility. Mater. Sci. Eng., A 375–377, 520 (2004)CrossRefGoogle Scholar
4.Kolbe, M., Gao, J.R.Liquid phase separation of Co–Cu alloys in the metastable miscibility gap. Mater. Sci. Eng., A 413–414, 509 (2005)CrossRefGoogle Scholar
5.Curiotto, S., Pryds, N.H., Johnson, E., Battezzati, L.Liquid–liquid phase separation and remixing in the Cu–Co system. Metall. Mater. Trans. A 37, 2361 (2006)CrossRefGoogle Scholar
6.Battezzati, L., Curiotto, S., Johnson, E., Pryds, N.H.Undercooling and demixing in rapidly solidified Cu–Co alloys. Mater. Sci. Eng., A 449–451, 7 (2007)CrossRefGoogle Scholar
7.Curiotto, S., Pryds, N.H., Johnson, E., Battezzati, L.Effect of cooling rate on the solidification of Cu58Co42. Mater. Sci. Eng., A 449–451, 644 (2007)CrossRefGoogle Scholar
8.Zhao, J.Z., Kolbe, M., Li, H.L., Gao, J.R., Ratke, L.Formation of the microstructure in a rapidly solidified Cu–Co alloy. Metall. Mater. Trans. A 38, 1162 (2007)CrossRefGoogle Scholar
9.Egry, B.L., Herlach, D., Kolbe, M., Ratke, L., Reutzel, S., Perrin, C., Chatain, D.Surface tension, phase separation, and solidification of undercooled cobalt-copper alloys. Adv. Eng. Mater. 5, (11)819 (2003)CrossRefGoogle Scholar
10.Zhao, J.Z., Li, H.L., Wang, Q.L., He, J.Kinetics of the microstructure formation in a rapid solidified immiscible alloy. Comput. Mater. Sci. 44, 400 (2008)CrossRefGoogle Scholar
11.Zhao, J.Z., Latke, R.A model describing the microstructure evolution during a cooling of immiscible alloys in the miscibility gap. Scr. Mater. 50, 543 (2004)CrossRefGoogle Scholar
12.Curiotto, S., Greco, R., Pryds, N.H., Johnson, E., Battezzati, L.The liquid metastable miscibility gap in Cu-based systems. Fluid Phase Equilib. 256, 132 (2007)CrossRefGoogle Scholar
13.Curiotto, S., Battezzati, L., Johnson, E., Pryds, N.N.Thermodynamics and mechanism of demixing in undercooled Cu–Co–Ni alloys. Acta Mater. 55, 6642 (2007)CrossRefGoogle Scholar
14.Curiotto, S., Battezzati, L., Johnson, E., Palumbo, M., Pryds, N.N.The liquid metastable miscibility gap in the Cu–Co–Fe system. J. Mater. Sci. 43, 3253 (2008)CrossRefGoogle Scholar
15.Wang, C.P., Liu, X.J., Ohnuma, I., Kainuma, R., Hao, S.M., Ishida, K.Phase equilibria in the Cu–Fe–Mo and Cu–Fe–Nb systems. J. Phase Equilib. 21, (1)54 (2000)CrossRefGoogle Scholar
16.Kaufman, L., Bernstein, H.Computer Calculation of Phase Diagram (Academic Press, New York 1970)Google Scholar
17.Saunders, N., Miodownik, A.P.CALPHAD (Calculation of Phase Diagrams)—A Comprehensive Guide (Pergamon Press, Oxford, UK 1998)Google Scholar
18.Lukas, H., Fries, S.G., Sundman, B.Computational Thermodynamics—The Calphad Method (Cambridge University Press, Cambridge, UK 2007)CrossRefGoogle Scholar
19.Wang, C.P., Liu, X.J., Ohnuma, I., Kainuma, R., Ishida, K.Formation of immiscible alloy powders with egg-type microstructures. Science 297, 990 (2002)CrossRefGoogle Scholar
20.Wang, C.P., Liu, X.J., Takaku, Y., Ohnuma, I., Kainuma, R., Ishida, K.Formation of core-type macroscopic morphologies in Cu–Fe base alloys with liquid miscibility gap. Metall. Trans. A 35, 1243 (2004)CrossRefGoogle Scholar
21.Liu, X.J., Jiang, Z.P., Wang, C.P., Ishida, K.Experimental determination and thermodynamic calculation of the phase equilibria in the Cu–Cr–Nb and Cu–Cr–Co systems. J. Alloys Compd. 478, 287 (2009)CrossRefGoogle Scholar
22.Kattner, U.R.The thermodynamic modeling of multicomponent phase equilibria. JOM 49, 14 (2003)CrossRefGoogle Scholar
23.Redlich, O., Kister, A.T.Thermodynamics of nonelectrolyte solutions-x-y-t relations in a binary system. Ind. Eng. Chem. 40, 341 (1948)CrossRefGoogle Scholar
24.Hillert, M., Jarl, M.A model for alloying effects in ferromagnetic metals. Calphad 2, 227 (1978)CrossRefGoogle Scholar
25.Hari Kumar, K.C., Ansara, I., Wollants, P., Delaey, L.Thermodynamic optimisation of the Co–Nb system. J. Alloys Compd. 267, 105 (1998)CrossRefGoogle Scholar
26.Kubišta, J., Vřešt’ál, J.Thermodynamics of the liquid Co–Cu system and calculation of phase diagram. J. Phase Equilib. 21, 125 (2000)CrossRefGoogle Scholar
27.Hämäläinen, M., Jääskeläinen, K., Luoma, R., Nuotio, M., Taskinen, P., Teppo, O.A thermodynamic analysis of the binary systems Cu–Cr, Cu–Nb and Cu–V. Calphad 14, (2)125 (1990)CrossRefGoogle Scholar
28.Wang, C.P., Liu, X.J., Shi, R.P., Shen, C., Wang, Y., Ohnuma, I., Kainuma, R., Ishida, K.Design and formation mechanism of self-organized core/shell structure composite powder in immiscible liquid system. Appl. Phys. Lett. 91, 141904 (2007)CrossRefGoogle Scholar
29.Nishizawa, T., Ohnuma, I., Ishida, K.Correlation between interfacial energy and phase diagram in ceramic-metal systems. J. Phase Equilib. 22, (3)269 (2001)CrossRefGoogle Scholar