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Synthesis of ultrafine nickel aluminide particles by the hydrogen reduction of vapor-phase mixtures of NiCl2 and AlCl3

Published online by Cambridge University Press:  31 January 2011

H. Y. Sohn
Affiliation:
Department of Metallurgical Engineering, University of Utah, Salt Lake City, Utah 84112–0114
S. PalDey
Affiliation:
Department of Metallurgical Engineering, University of Utah, Salt Lake City, Utah 84112–0114
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Abstract

Fine particles of nickel aluminides were synthesized for the first time by reducing mixtures of AlCl3 + NiCl2 vapors by hydrogen. A thermodynamic equilibrium calculation was carried out in the Ni–Al–H–Cl–Ar system to evaluate the effect of the reactant partial pressures and temperature on the formation of intermetallic phases. A single intermetallic phase was found to be feasible only in a very narrow range of the reactant partial pressures. For all other conditions the predicted solid product was a mixture of two phases. Experimentally, Ni3Al was formed along with metallic Ni. Though the coreduction of NiCl2 and AlCl3 by H2 to form Ni3Al is thermodynamically favorable at 1100 °C, it did not happen experimentally under the conditions of this work. However, with a small addition of aluminum vapor, the coreduction reaction proceeded as expected by thermodynamics. The effects of reactant partial pressures and temperature were studied. The content of Ni3Al was maximized to 52 mol% at 1050 °C under the partial pressures of H2, AlCl3, and NiCl2 at 57, 1.5, and 0.5 kPa, respectively. The product particles, as observed by TEM, were very fine, but usually agglomerated. The electron diffraction analysis identified the particles of NiAl and NiAl3 along with Ni3Al and metallic Ni.

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Articles
Copyright
Copyright © Materials Research Society 1998

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References

REFERENCES

1.Thornton, P. H, Davies, R. G, and Johnston, T. L, Metall. Trans. 1, 209218 (1970).Google Scholar
2.Lamprey, H and Ripley, R. L, J. Electrochem. Soc. 109 (8), 713715 (1962).CrossRefGoogle Scholar
3.Saeki, Y, Zaki, R. M, Nishikara, H, and Ayoama, N, Denki Kagaku 46 (12), 613617 (1978).Google Scholar
4.Otsuka, K, Yamamoto, H, and Yoshizawa, A, J. Chem. Soc. Jpn., no. 6, 869878 (1984).Google Scholar
5.Zhao, G. Y, Revenkar, V. V. S, and Hlavacek, V, J. Less Common Metals 163 (2), 269280 (1990).CrossRefGoogle Scholar
6.Hojo, J, Oku, T, and Kato, A, J. Less Common Metals 59 (1), 8595 (1978).CrossRefGoogle Scholar
7.Barin, I, Thermochemical Data of Pure Substances, Parts I and II (VCH Verlagsgesellschaft mbH, D-6940 Weinheim, Germany, 1987).Google Scholar
8.JANAF Thermochemical Tables, 2nd ed., Stull, D. R and Prophet, H, Project Directors, NSRDS-NBS 37 (Office of Standard Reference Data, Washington, D.C. 20234, June 1971).Google Scholar
9.Pankratz, L. B, Thermodynamic Properties of Halides, U.S. Dept. of Interior, of Mines, Bulletin 674, 1987.Google Scholar
10.PalDay, s, Synthesis of Intermetallic Compounds by Vapor-Phase Coreduction of Metal Chlorides, Ph.D. Dissertation, University of Utah, Salt Lake City, Utah, 1995.Google Scholar
11.Sohn, H. Y and PalDey, S, “Synthesis of Ultrafine Particles of Intermetallic Compounds by the Vapor-Phase Magnesium Reduction of Chloride Mixtures: Part I. Titanium Aluminides,” Metall. Trans. B (in press).Google Scholar
12.Sohn, H. Y and PalDey, S, “Synthesis of Ultrafine Particles of Intermetallic Compounds by the Vapor-Phase Magnesium Reduction of Chloride Mixtures: Part II. Nickel Aluminides,” Metall. Trans. B (in press).Google Scholar
13.Sohn, H. Y and PalDey, S, “Synthesis of Ultrafine Particles and Thin Films of Ni4Mo by the Vapor-Phase Hydrogen Coreduction of the Constituent Metal Chlorides,” Mater. Sci. Eng. A (in press).Google Scholar