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Fe–Cr/Al2O3 metal-ceramic composites: Nature and size of the metal particles formed during hydrogen reduction

Published online by Cambridge University Press:  03 March 2011

Ch. Laurent ,
J.J. Demai ,
A. Rousset ,
K.R. Kannan  and
C.N.R. Rao
Ch. Laurent
Affiliation:
Laboratoire de Chimie des Materiaux Inorganiques, URA CNRS 1311, Université Paul-Sabatier, 31062 Toulouse Cedex, France
J.J. Demai
Affiliation:
Laboratoire de Chimie des Materiaux Inorganiques, URA CNRS 1311, Université Paul-Sabatier, 31062 Toulouse Cedex, France
A. Rousset
Affiliation:
Laboratoire de Chimie des Materiaux Inorganiques, URA CNRS 1311, Université Paul-Sabatier, 31062 Toulouse Cedex, France
K.R. Kannan
Affiliation:
Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
C.N.R. Rao*
Affiliation:
Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore 560012, India
*
a)Author to whom correspondence should be addressed.
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Abstract

Fe-Cr/Al2O3 metal-ceramic composites prepared by hydrogen reduction at different temperatures and for different periods have been investigated by a combined use of Mössbauer spectroscopy, x-ray diffraction, transmission electron microscopy, and energy-dispersive x-ray spectroscopy in order to obtain information on the nature of the metallic species formed. Total reduction of Fe3+ does not occur by increasing the reduction time at 1320 K from 1 to 30 h, and the amount of superparamagnetic metallic species is essentially constant (about 10%). Temperatures higher than 1470 K are needed to achieve nearly total reduction of substitutional Fe3+. Interestingly, iron favors the reduction of chromium. The composition of the Fe-Cr particles is strongly dependent on their size, the Cr content being higher in particles smaller than 10 nm.

Type
Articles
Information
Journal of Materials Research , Volume 9 , Issue 1 , January 1994 , pp. 229 - 235
Copyright
Copyright © Materials Research Society 1994

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References

REFERENCES

1Niihara, K., J. Ceram. Soc. Jpn. 99 (10), 974 (1991).CrossRefGoogle Scholar
2Devaux, X., Laurent, Ch., Brieu, M., and Rousset, A., Composite Materials, edited by DiBenedetto, A. T., Nicolais, L., and Watanabe, R. (Elsevier Science Publishing BV, Amsterdam, 1992), p. 209.Google Scholar
3Devaux, X., Laurent, Ch., Brieu, M., and Rousset, A., C. R. Acad. Sci. Paris, Series II 312, 1425 (1991).Google Scholar
4Breval, E., Deng, Z., Chiou, S., and Pantano, C. G., J. Mater. Sci. 27, 1464 (1992).CrossRefGoogle Scholar
5Klomp, J. T. and Lindenhovius, R. H., Ceram. Int. 4, 59 (1978).CrossRefGoogle Scholar
6Roy, R. A. and Roy, R., Mater. Res. Bull. XIX, 169 (1984).CrossRefGoogle Scholar
7Subbanna, G. N. and Rao, C. N. R., Mater. Res. Bull. XXI, 1465 (1986).CrossRefGoogle Scholar
8Devaux, X., Laurent, Ch., and Rousset, A., Nanostructured Materials (in press).Google Scholar
9Verelst, M., Kannan, K. R., Subbanna, G. N., Rao, C. N. R, Laurent, Ch., and Rousset, A., J. Mater. Res. 7, 3072 (1992).CrossRefGoogle Scholar
10Laurent, Ch., Rousset, A., Verelst, M., Kannan, K. R., Raju, A. R., and Rao, C. N. R., J. Mater. Chem. 3, 513 (1993).CrossRefGoogle Scholar
11Verelst, M., Kannan, K. R., Subbanna, G. N., Rao, C. N. R, Brieu, M., and Rousset, A., Mater. Res. Bull. XXVIII, 293 (1993).CrossRefGoogle Scholar
12Chatterjee, A., Das, D., Chakravorty, D., and Choudhury, K., Appl. Phys. Lett. 57 (13), 1360 (1990).CrossRefGoogle Scholar
13Gong, W., Li, H., Zhao, Z., Hadjipanayis, G. C., Papaefthymiou, V. P., Kostikas, A., and Simopouos, A., J. Appl. Phys. 70 (10), 5900 (1991).CrossRefGoogle Scholar
14Matteazzi, P. and LëCaer, G., J. Am. Ceram. Soc. 75 (10), 2749 (1992).CrossRefGoogle Scholar
15Muan, A. and Sōmiya, S., J. Am. Ceram. Soc. 42 (12), 603 (1959).CrossRefGoogle Scholar
16Dubiel, S. M. and Zukrowski, J., J. Magn. Magn. Mater. 23, 214 (1981).CrossRefGoogle Scholar
17Dubiel, S. M. and Zinn, W., Phys. Rev. B 26 (4), 1574 (1982).CrossRefGoogle Scholar
18Devaux, X., Laurent, Ch., Brieu, M., and Rousset, A., J. Alloys and Compounds 188, 179 (1992).CrossRefGoogle Scholar
19Marchand, A., Devaux, X., Barbara, B., Mollard, P., Brieu, M., and Rousset, A., J. Mater. Sci. 28, 2217 (1993).CrossRefGoogle Scholar