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Autori: I. Chicinaş, V. Pop, O. Isnard, J.M. Le Breton, J. Juraszek
Editorial: Journal of Alloys and Compounds, 352, p.34-40, 2003.
Nanocrystalline Ni3Fe intermetallic compound has been obtained by milling of iron and nickel powders under argon atmosphere. Several milling times have been used ranging from 1 h up to 52 h. The formation of the Ni3Fe intermetallic compound by mechanical alloying was evidenced by X-ray diffraction and 57Fe Mo¨ssbauer spectroscopy. A heat treatment of 1 h at 330 C relaxes the first and second order internal stresses and favours the solid-state reaction. The reaction becomes significant after 4 h of milling and subsequent heat treatment. A typical particle size of 12.5+-2.0 nm has been obtained after 52 h. Scanning electron microscopy and X-ray microanalysis studies show the evolution of the chemical homogeneity of the particles and reveal the morphology upon Ni3Fe phase formation. Magnetic measurements have been performed in a magnetic field up to 8 Tesla between 4 and 300 K. The influence of the synthesis conditions on the magnetic properties of Ni Fe is discussed.
Cuvinte cheie: Transition metal compounds; Mechanical alloying; Magnetic measurements; Mo¨ssbauer spectrometry