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Structural and Magnetic Properties of Fe/Al2O3, Granular Systems

Published online by Cambridge University Press:  28 February 2011

J.L. Dormann  and
D. Fiorani
J.L. Dormann
Affiliation:
Laboratoire de Magnétisme, CNRS, 92195 Meudon-Cedex, France
D. Fiorani
Affiliation:
ITSE, CNR, CPlO. 00016 Monterotondo Stazione, Italia
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Abstract

Several samples of granular material consisting of Fe small particles dispersed in an alumina matrix were studied by means of various techniques. Structural results show that the particle surface is partially oxidized with occurrence of bonds with the matrix. Depending on the particle size, one observes b.c.c. a-Fe or amorphous structure. Magnetic properties are relevant of superparamagnetism phenomena, but the strong magnetic interactions between particles (due to the close compact arrangement) lead to a phase transition at zero temperature. It is also briefly discussed the magnetic volume determination and the influence on the properties of the magnetic disorder arising at the particle surface.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 195: Symposium S – Physical Phenomena in Granular Materials , 1990 , 429
Copyright
Copyright © Materials Research Society 1990

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References

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