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A time-resolved diffraction study of the Ta–C solid combustion system

Published online by Cambridge University Press:  31 January 2011

E.M. Larson,
Joe Wong,
J.B. Holt,
P.A. Waide,
G. Nutt,
B. Rupp and
L.J. Terminello
E.M. Larson
Affiliation:
Lawrence Livermore National Laboratory, University of California, P.O. Box 808, Livermore, California 94551
Joe Wong
Affiliation:
Lawrence Livermore National Laboratory, University of California, P.O. Box 808, Livermore, California 94551
J.B. Holt
Affiliation:
Lawrence Livermore National Laboratory, University of California, P.O. Box 808, Livermore, California 94551
P.A. Waide
Affiliation:
Lawrence Livermore National Laboratory, University of California, P.O. Box 808, Livermore, California 94551
G. Nutt
Affiliation:
Lawrence Livermore National Laboratory, University of California, P.O. Box 808, Livermore, California 94551
B. Rupp
Affiliation:
Lawrence Livermore National Laboratory, University of California, P.O. Box 808, Livermore, California 94551
L.J. Terminello
Affiliation:
Lawrence Livermore National Laboratory, University of California, P.O. Box 808, Livermore, California 94551
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Abstract

The formation of TaC and Ta2C by combustion synthesis from their elemental constituents has been studied by time-resolved x-ray diffraction (TRXRD) using synchrotron radiation. The reactions have been followed with a time resolution down to 50 ms. Since the adiabatic temperatures for both reactions are well below any liquidus temperature in the Ta—C phase diagram, no melting occurs and these combustion reactions occur purely in the solid state. The phase transformations associated with these reactions are followed by monitoring the disappearance of reactant and appearance of product powder diffraction peaks in real time as the reaction front propagates through the combusting specimen. In the synthesis of TaC, the results show the formation of the subcarbide (Ta2C phase as an intermediate. In the synthesis of Ta2C, the reaction proceeds directly to the product with no discernible intermediate Ta–C phase within a 50 ms time frame. The chemical dynamics associated with the combustion synthesis of TaC may be described by an initial phase transformation to hexagonal Ta2C arising from carbon diffusion into the Ta metal lattice. As more carbon is available this intermediate subcarbide phase, which has one-half of its octahedral interstices occupied by the carbon, further transforms to the cubic TaC final product, in which all octahedral sites are now occupied. The time-resolved data indicate that the rate of formation of Ta2C is a factor of two faster than that of TaC.

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Articles
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Journal of Materials Research , Volume 8 , Issue 7 , July 1993, pp. 1533 - 1541
Copyright
Copyright © Materials Research Society 1993

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References

REFERENCES

1(a) Munir, Z.A.Ceram. Bull. 67 (2), 342 (1988); (b) Z.A. Muni r and U. Anselmi Tamburini, Mater. Sci. Rep. 3, 277 (1989).Google Scholar
2Merzhanov, A. G. in Combustion and Plasma Synthesis of High-Temperature Materials, edited by Munir, Z. A. and Holt, J. B. (VCH Publishers, New York, 1990) , pp. 1–53.Google Scholar
3Merzhanov, A. G.Ceram. Trans. 13, 519 (1990).Google Scholar
4Lebrat, J.P. and Varma, A.Physica C 184, 220–228 (1991).CrossRefGoogle Scholar
5Boldyrev, V. V. and Aleksandrov, V.Dok. Akad. Nauk SSSR 259, 1127 (1981).Google Scholar
6Wong, J.Larson, E.M.Holt, J.B.Waide, P.Rupp, B. and Frahm, R.Science 249, 1406 (1990).CrossRefGoogle Scholar
7Frahm, R.Wong, J.Holt, J.B., Larson, E.M., Rupp, B. and Waide, P. A., Phys. Rev. B 46, 9205 (1992).CrossRefGoogle Scholar
8Winick, H. in Synchrotron Radiation Research, edited by Winick, H. and Doniach, S. (Plenum Press, New York, 1980), Chaps. 1 and 2, pp. 1–26.CrossRefGoogle Scholar
9Binary Alloy Phase Diagrams, edited by Massalski, T. B.Murray, J. L.Bennett, L. H. and Baker, H. (ASM, Metals Park, OH, 1986), Vol. 1.Google Scholar
10Shkiro, V. M.Nersisyan, G. A. and Borovinskaya, I. P.Fiz. Goreniya Vzryva 14, 58 (1978).Google Scholar
11Shkiro, V. M.Nersisyan, G.A.Borovinskaya, I. P.Merzhanov, A.G., and Shokhtman, V. Sh.Poroshkovay a Metallurgiya 4, 14 (1979).Google Scholar
12Shkiro, V. M. and Nersisyan, G. A.Fiz. Goreniya Vzryva 14, 149 (1978).Google Scholar
13Larson, E.M.Waide, P.A. and Wong, J.Rev. Sci. Instmm. 62 (1), 53–57 (1991).CrossRefGoogle Scholar
14Novikov, N. P.Borovinskaya, I. P. and Merzhanov, A. G.Protesessy Goreniya Khimicheskayai Tekhnologiii Metallurgii (Combustion Processes in Chemical Technology and Metallurgy) (Chernoglovka, 1975),edited by Merzhanov, A. G.. (For English translation, write to LLNL, P.O. Box 5500, Livermore, CA 94551 and ask for LLL Ref. 03007.)Google Scholar
15Barin, I. and Knacke, O.Thermodynamic properties of inorganic substances (Springer-Verlag, Berlin, 1973); ibid., supplement (1977).Google Scholar
16Rupp, B.Holt, J.B. and Wong, J.Calphad 16 (4), 377–386 (1992).CrossRefGoogle Scholar
17Gavrish, A. A.Glazunov, M. P.Korolev, Yu. M.Spitsyn, V. I. and Fedoseev, G. K.Russ. J. Inorg. Chem. 20, 1269 (1975).Google Scholar
18Bolz, R. E. and Ture, G. L.Handbook of Tables for Appl. Eng. Sci., (The Chemical Rubber Co. 1970), p. D–173.Google Scholar
19Spivak, I.I. and Klimenko, V.V.Fiz. Met. Metalloved. 32, 314 (1971).Google Scholar
20Wells, A. F.. Structural Inorganic Chemistry, 4th ed. (Oxford Univ. Press, 1975), p. 760.Google Scholar
21Mueller, M.H.Scripta Metall. 11, 693 (1977).CrossRefGoogle Scholar
22Sedivy, J.Sichova, H. and Vaneckova, H.Freiberg. Forschungsh Reihe B 129, 95 (1968).Google Scholar
23Korolev, Yu. M.Gavrish, A. A.Glazunov, M. P.Spitsyn, V. I. and Fedoseev, G.K.Russ. J. Inorg. Chem. 20, 1591–1592 (1975).Google Scholar