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A Comparison of the Surface Composition of Solid and Liquid Alloys

Published online by Cambridge University Press:  25 February 2011

J. A. Barnard
Affiliation:
Carnegie-Mellon University, Dept. of Metallurgical Engineering and Materials Science, Pittsburgh, PA 15213
P. Wynblatt
Affiliation:
Carnegie-Mellon University, Dept. of Metallurgical Engineering and Materials Science, Pittsburgh, PA 15213
William C. Johnson
Affiliation:
Carnegie-Mellon University, Dept. of Metallurgical Engineering and Materials Science, Pittsburgh, PA 15213
W.W. Mullins
Affiliation:
Carnegie-Mellon University, Dept. of Metallurgical Engineering and Materials Science, Pittsburgh, PA 15213
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Abstract

The surface compositions of three In-Pb alloys (1.42a/o Pb, 3.07a/o Pb, and 5.86a/o Pb) have been obtained as a function of temperature in both solid and liquid states using a scanning Auger microprobe. All data were obtained at temperature, from equilibrated samples in a region of about fifty degrees on either side of the liquidus temperature. Lead was found to be the segregating component in all cases. From these measurements, the heat of segregation has been calculated for all alloys in both states. In each alloy the magnitude of the heat of segregation declines significantly on melting although the absolute surface compositions are found to be continuous across the two phase solid-liquid field. These results are interpreted in the light of current segregation theories. Particular attention is paid to the role of elastic effects on solute segregation to free surfaces.

Type
Research Article
Copyright
Copyright © Materials Research Society 1987

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References

REFERENCES

[1] Gibbs, J. W., The Scientific Papers of J. Willard Gibbs, v.1. Thermodynamics (Dover Publication, Inc., New York, 1961) p.219 Google Scholar
[2] Abraham, F. F. and Brundle, C.R., J.Vac.Sci.Technol. 18, no.2 506 (1981)Google Scholar
[3] Kelley, M., J.Catalysis 57 113 (1979)Google Scholar
[4] Wynblatt, P. and Ku, R.C., in Interfacial Segregation, edited by Johnson, W.C. and Blakely, J.M. (American Society for Metals, Metals Park, OH, 1979) pp.115136 Google Scholar
[5] Barnard, J. A., Wynblatt, P., Johnson, W.C. and Mullins, W.W., Surf. Sci. (in press)Google Scholar
[6] Alcock, C. B., Itkin, V.P., and Horrigan, M.K., Can.Met.Qrtly. 23, no.3 309 (1984)Google Scholar
[7] Hultgren, R. et al, Selected Properties of the Thermodynamic Properties of Binary Alloys (American Society for Metals, Metals Park, OH, 1973)Google Scholar
[8] Berglund, S. and Somorjai, G.A., J.Chem.Phys. 59 no.10 5537 (1973)Google Scholar
[9] Lea, C. and Seah, M.P., Phil.Mag. 35 213 (1977)Google Scholar
[10] Frankenthal, R. P. and Siconolfi, D.J., Surf.Sci. 119 331 (1982)CrossRefGoogle Scholar
[11] Pauling, L., The Nature of the Chemical Bond, 3rd edition (Cornell University Press, Ithaca, New York, 1960) p393 Google Scholar
[12] Brundle, C. R., J.Vac.Sci.Technol. 11 212 (1974)Google Scholar
(13) Penn, D. R., J.Elect.Spect. 9 29 (1976)Google Scholar
[14] Hall, P. M. and Morabito, J.M., Surf.Sci. 83 391 (1979)Google Scholar
[15] Blakely, J. M. and Shelton, J.C., in Surface Physics of Materials, v.1., edited by Blakely, J.M (Academic Press, New York, 1975)Google Scholar
[16] McLean, D., Grain Boundaries in Metals (Oxford Univ. Press, London, 1957)Google Scholar
[17] Friedel, J., Advan.Phys. 3 446 (1954)Google Scholar