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Measuring Enthalpies of Formation Using Thick Multilayer Foils and Differential Scanning Calorimetry

Published online by Cambridge University Press:  15 February 2011

T.P. Weihs ,
T.W. Barbee Jr.  and
M.A. Wall
T.P. Weihs
Affiliation:
Lawrence Livermore National Laboratory, Livermore, CA 94551
T.W. Barbee Jr.
Affiliation:
Lawrence Livermore National Laboratory, Livermore, CA 94551
M.A. Wall
Affiliation:
Lawrence Livermore National Laboratory, Livermore, CA 94551
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Abstract

The exothermic, solid state reaction of Al and Zr has been studied in thick AL/Zr multilayers using Differential Scanning Calorimetry and X-ray diffraction. The multilayersamples were magnetron sputter deposited into highly textured alternate layers of Al and Zr with nominal composition A13Zr. The samples used in this study were 47μm thick with a 427Å period. When samples were isochronally scanned from 25º to 725ºC, a large exotherm at ˜350ºC was followed by one or two smaller exotherms at ˜650ºC. The first exotherm is dominated by a diffusionbased reaction of Al and Zr that produces two phases in isochronal scans: amorphous AI-Zrand cubic A13Zr, and two additional phases in isothermal anneals: A12Zr and tetragonal AI3Zr. The exothermic heat from this multi-phase reaction is measured using isochronal scans and isothermal anneals, and the heat flow is analyzed using a l-D diffusion based model. An average activation energy and a diffusion constant are determined. In the isothermal scans, the total exothermic heat increases linearly with √ime, and layer thicknesses vary linearly with heat.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 382: Symposium G – Structure and Properties of Multilayered Thin Films , 1995 , 21
Copyright
Copyright © Materials Research Society 1995

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References

REFERENCES

1) Johnson, W.L., Mater. Sci. and Eng., 97, 1 (1988).Google Scholar
2) Mat. Res. Soc. Proceedings, Vol 311, edited by Atzmon, M., Greer, A.L., Harper, J.M., and Liberia, M.R., Spring 1993.Google Scholar
3) Clevenger, L.A., Thompson, C.V., Cammarata, R.C., and Tu, K.N., Appl. Phys. Lett., 52, 795 (1988).Google Scholar
4) Highmore, R.J., Evetts, J.E., Greer, A.L., and Somekh, R.E., Appl. Phys. Lett., 50, 566 (1987).Google Scholar
5) Kleppa, O.J., J. Phase Equil., 15, 240 (1994).Google Scholar
6) Kubaschewski, O. and Alcock, C.B., Metallurgical Thermochemistry, Pergamon Press, NY, 1979.Google Scholar
7) Barbee, T. W. Jr., “Multilayer Synthesis by Physical Vapor Deposition” in Synthetic Modulated Structures, ed. by Chang, L. and Giessen, B. C., (Academic Press, New York, 1985), pp. 313–337.Google Scholar
8) Anamet Laboratories, Inc., 3400 Investment Blvd., Hayward CA 94545.Google Scholar
9) Weihs, T.P., Barbee, T.W. Jr., Wall, M.A., submitted to J. Mater. Res.Google Scholar
10) Blobaum, K., Weihs, T.P., barbee, T.W. Jr., and Wall, M.A., this symposium.Google Scholar
11) Weihs, T.P., Barbee, T.W. Jr., Wall, M.A., Mat. Res. Soc. Proceedings, Vol 311, edited by Atzmon, M., Greer, A.L., Harper, J.M., and Liberia, M.R., Spring 1993.Google Scholar
12) Kleppa, O.J. and Wanatabe, S., Metall. Trans. B, 13, 391 (1982).Google Scholar
13) Murray, J., Peruzzi, A., and Abriata, J.P., J. Phase Equil., 13, 277 (1992).Google Scholar
14) Kematick, R.J. and Franzen, H. F., J. of Sol. State Chem., 54, 226 (1984).Google Scholar
15) Meschel, S.V. and Kleppa, O.J., J. of Alloys and Comp., 191, 111 (1993).Google Scholar