Extended X-ray absorption fine structure (EXAFS) and X-ray absorption near-edge structure (XANES) study of melt-spun Fe85Ga15 ribbons

The local structure in melt-spun Fe₈₅Ga₁₅ ribbons with a width ∼3 mm and thickness ∼60 μm produced in argon atmosphere was studied by analyzing EXAFS and XANES data. The following results were obtained: Ga–Ga bonds were not detected excluding the tendency to form clusters of Ga atoms; Ga substitutes Fe creating a local strain of about +1% on the first shell Fe–Ga bond, whereas on the second Fe–Ga shell strain quickly relaxes down to +0.3%; XANES spectra are compatible with a random substitution of Fe atoms by Ga atoms in the A2 structure. From the AFM investigation, we observed that at the surface (free side) of the ribbon the particles are elongated along the ribbon (∼2 μm×∼5 μm) and each particle is formed by small grains of average size of 200 nm.