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Metastable phase formation by ion mixing of Nb–Al multilayers

Published online by Cambridge University Press:  31 January 2011

K. Pampus
Affiliation:
Institute of Physics, University of Aarhus, DK-8000 Aarhus C, Denmark
K. Dyrbye
Affiliation:
Institute of Physics, University of Aarhus, DK-8000 Aarhus C, Denmark
B. Torp
Affiliation:
Institute of Physics, University of Aarhus, DK-8000 Aarhus C, Denmark
R. Bormann
Affiliation:
Institut für Metallphysik, Universität Göttingen, Hospitalstr. 3-5, D-3400 Göttingen, Federal Republic of Germany
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Abstract

The structure of Nb–Al thin films after ion mixing was studied for compositions from 20 to 85 at. % Al as a function of temperature in the range between 40 and 620 K. The phase formation was determined by transmission electron microscopy. At lower temperatures, only supersaturated bcc-solid solution, NbAl, and amorphous phase were found throughout the studied composition range. Besides these phases irradiation at temperatures above 470 K causes the formation of a metastable crystalline compound at an overall composition close to Nb25Al75, and for T = 623 K the equilibrium compound NbAl3 is formed. The other intermetallic phases Nb2Al and Nb3Al have not been observed at any irradiation temperature. Calculations of the Gibbs free energies of the various phases are presented, and the reliability of extrapolations to regions of metastability with respect to temperature and composition is commented on. The phase formation during heavy-ion irradiation is discussed in the context of the calculated free energies and kinetic constraints. For temperatures above 300 K, the attainment of a metastable phase equilibrium between the bcc solid solution and the amorphous phase is proposed due to the influence of radiation enhanced diffusion.

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Articles
Copyright
Copyright © Materials Research Society 1989

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References

REFERENCES

1Averback, R. S.Nucl. Instrum. Methods B15, 675 (1986).Google Scholar
2Bottiger, J., Mikkelsen, N. J.Nielsen, S. K.Weyer, G. and Pampus, K.J. Non-Cryst. Solids 76, 303 (1985).CrossRefGoogle Scholar
3Bottiger, J.Pampus, K. and Torp, B.Nucl. Instrum. Methods B19/20, 696 (1987).Google Scholar
4Bormann, R.Yu, D.Y.Hammond, R.H.Marshall, A. and Geballe, T. H. in Rapidly Quenched Metals V, edited by Steeb, S. and Warlimont, H. (North-Holland, 1985), p. 879.CrossRefGoogle Scholar
5Kammerdiner, L. and Luo, H.L.J. Appl. Phys. 43, 4728 (1972).CrossRefGoogle Scholar
6Bormann, R.Krebs, H. U. and Kent, A. D.Adv. Cryogen. Engineering 32, 1041 (1986).Google Scholar
7Gavaler, J.R.Braginski, A. J.Greggi, J. and Schulze, K.J. Appl. Phys. 61, 659 (1987).CrossRefGoogle Scholar
8Hellstern, E.Schultz, L.Bormann, R. and Lee, D.Appl. Phys. Lett. 53, 1399 (1988).CrossRefGoogle Scholar
9Schneider, U.Linker, G. and Meyer, O.J. Low Temp. Phys. 47, 439 (1982).CrossRefGoogle Scholar
10Liu, B. X.Johnson, W. L.Nicolet, M.A. and Lau, S. S.Nucl. Instrum. Methods 209/210, 229 (1983).CrossRefGoogle Scholar
11Rai, A.K.Bhattacharya, R.S.Mendiratta, M. G. and Subramanian, P. R., J. Mater. Res. 3, 1082 (1988).CrossRefGoogle Scholar
12Sweedler, A.R. and Cox, D.E.Phys. Rev. B12, 147 (1975).Google Scholar
13Bormann, R. Habilitation Thesis, Gottingen, 1988.Google Scholar
14Kaufman, L. and Bernstein, H.Computer Calculations of Phase Diagrams (Academic Press, New York, 1970).Google Scholar
15Kaufman, L. and Nesor, H.CALPHAD 2, 325 (1978).Google Scholar
16Jorda, J.L.Flukiger, R. and Muller, J.J. Less-Common Met. 5, 227 (1980).Google Scholar
17Shilo, I.Franzen, H. F. and Schiffman, R. A.J. Electrochem. Soc. 129, 1608 (1982).Google Scholar
18Malets, G. A.Vest. Akad. Nauk SSR Ser. Khim Navuk 6, 127 (1974).Google Scholar
19Neckel, A. and Nowotny, H. Proc 5. Intern. Leichtmetalltagung Diis-seldorf, 1969, p. 72.Google Scholar
20Bulletin of Alloy Phase Diagrams 2, 75 (1981).Google Scholar
21Bormann, R.Gartner, F. and Zoltzer, K.J. Less-Common Met. 145, 19 (1988).CrossRefGoogle Scholar
22Cheng, Y. T.Rossum, M. van, Nicolet, M.A. and Johnson, W. L.Appl. Phys. Lett. 45, 185 (1984).CrossRefGoogle Scholar
23Johnson, W.L.Progr. Mat. Science 30, 81 (1986).CrossRefGoogle Scholar
24Lin, C.J. and Spaepen, F.Appl. Phys. Lett. 41, 721 (1982); Acta Metall. 34, 1367 (1986).CrossRefGoogle Scholar
25Matteson, S.Roth, J. and Nicolet, M.A.Radiat. Eff. 42, 217 (1979).CrossRefGoogle Scholar
26Bottiger, J., Nielsen, S. K. and Thorsen, P. T. in Amorphous Metals and Non-Equilibrium Processing, edited by Allmen, M. von (Les editions de physique, 1984), p. 111.Google Scholar
27Cheng, Y.T.Zhao, X.A.Banwell, T.Workman, T. W.Nicolet, M.A. and Johnson, W.L.J. Appl. Phys. 60, 2615 (1986).CrossRefGoogle Scholar
28Tsaur, B.Y.Lau, S. S.Hung, L. S. and Mayer, J. W.Nucl. Instrum. Methods 182/183, 67 (1981).CrossRefGoogle Scholar
29Bottiger, J., Dyrbye, K.Pampus, K. and Poulsen, R. in Proc. 6th Int. Conf. on Ion-Beam Modification of Materials, Tokyo, Japan, 1988 (to be published).Google Scholar
30Sawicki, J. A. and Sawicka, B.D.Hyp. Int. 13, 199 (1983).CrossRefGoogle Scholar
31Brimhall, J. L.Kissinger, H. E. and Chariot, L. A.Radiat. Eff. 77, 237 (1983).CrossRefGoogle Scholar
32Hung, L. S.Nastasi, M.Gyulai, J. and Mayer, J. W.J. Appl. Phys. 59, 4011 (1986).Google Scholar
33Barin, I. and Knacke, O.Thermochemical Properties of Inorganic Substances (Springer, Berlin, 1973).Google Scholar
34Saunders, N.Miodownik, A. P. and Dinsdale, A.T.Calphad 12, 351 (1988).Google Scholar
35Wollenberger, H. J. in Physical Metallurgy, edited by Cahn, R. W. and Haasen, P. (North-Holland, Amsterdam, 1983), p. 1140.Google Scholar
36Hirth, J.P. and Lothe, J.Theory of Dislocations (Wiley, New York, 1982), p. 836.Google Scholar