Title: Solid state amorphisation of mechanically alloyed Fe-Co-Nb-B alloys

Authors: R. Bensalem, A. Younes, S. Alleg, S. Souilah, S. Azzaza, J.J. Sunol, J.M. Greneche

Addresses: Laboratoire de Magnetisme et spectroscopie des Solides, Department de Physique Universite de Annaba, B.P. 12, 23000, Annaba, Algerie. ' Laboratoire de Magnetisme et spectroscopie des Solides, Department de Physique Universite de Annaba, B.P. 12, 23000, Annaba, Algerie. ' Laboratoire de Magnetisme et spectroscopie des Solides, Department de Physique Universite de Annaba, B.P. 12, 23000, Annaba, Algerie. ' Laboratoire de Magnetisme et spectroscopie des Solides, Department de Physique Universite de Annaba, B.P. 12, 23000, Annaba, Algerie. ' Laboratoire de Magnetisme et spectroscopie des Solides, Department de Physique Universite de Annaba, B.P. 12, 23000, Annaba, Algerie. ' Department de Fisica, Universitat de Girona, Campus Montilivi, Girona 17071, Spain. ' Laboratoire de Physique de L'Etat Condense, UMR CNRS 6087, Institut de Recherche en Ingenierie Moleculaire et Materiaux Fonctionnels, IRIM2F, FR CNRS 2575, Universite du Maine 72085, Le Mans Cedex 9 France

Abstract: Fe61Co21Nb3B15 powder mixture was prepared by mechanical alloying process in a high energy planetary ball mill. Structural and thermal changes of the milled powders were followed by X-ray diffraction (XRD), Mossbauer spectrometry and differential scanning calorimetry (DSC). Both XRD and Mossbauer spectrometry results reveal the formation, after 48 h of milling, of a highly disordered amorphous-like structure where nanometer-sized iron borides were embedded. A mechanical recrystallisation process gives rise to the formation of α-Fe and α-FeCo nanograins on further milling. The occurrence of structural disorder in the milled powders might be confirmed by broad exothermic reaction in the DSC scans which consists of several overlapping exothermic peaks. Such behaviour originates from recovery, strain relaxation, grain growth and crystallisation.

Keywords: nanostructure; mechanical alloying; solid state amorphisation; Fe-Co-Nb-B alloys; X-ray diffraction; XRD; Mossbauer spectrometry; nanoparticles; nanotechnology; planetary ball milling; iron boride; recovery; strain relaxation; grain growth; crystallisation; cobalt; niobium; boron.

DOI: 10.1504/IJNP.2011.038251

International Journal of Nanoparticles, 2011 Vol.4 No.1, pp.45 - 52

Received: 03 May 2010
Accepted: 13 May 2010

Published online: 13 Mar 2015 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article