The formation mechanism of mechanically alloyed Fe–20at% Al powder

F. Hadef (1) , A. Otmani (1) , A. Djekoun (2) , Jean-Marc Greneche (3)

1 Université 20 Août 1955 Skikda
2 UBMA - Université Badji Mokhtar [Annaba]
3 IMMM - Institut des Molécules et Matériaux du Mans

The formation mechanism of the mechanically alloyed Fe–20 at% Al, from elemental Fe and Al powders, has been investigated. The experimental results indicate the formation of a nanocrystalline bcc α-Fe(Al) solid solution with a lattice parameter close to aα−Fe(Al)=0.2890 nm, where each Fe atom is surrounded by (6Fe+2Al) in the first coordination sphere. The reaction mechanism of MA process seems to be controlled by a diffusion phenomenon. Aluminum particles undergo an important refinement to the nanometer scale and then they stick on Fe particles of large sizes. A large number of clear Al/Fe interface areas were generated. The short diffusion path and the presence of high concentration of defects accelerated the solid state reaction.

Mots clés: Fe–Al alloys; Mechanical alloying; X-ray diffraction; 57Fe Mössbauer spectrometry

Domaines: Matière Condensée [cond-mat]; Physique [physics]

F. Hadef, A. Otmani, A. Djekoun, Jean-Marc Greneche. The formation mechanism of mechanically alloyed Fe–20at% Al powder. Journal of Magnetism and Magnetic Materials, 2013, 326, pp.261-265. ⟨10.1016/j.jmmm.2012.09.019⟩. ⟨hal-02269892⟩