Magnetic Properties of FeCoNbB Nanocrystalline Alloys Heat treated under longitudinal magnetic field

The formation of a nanocrystalline structure and its influence on the magnetic properties was investigated in the melt-spun Fe81Nb7B12 and (FeCo)81Nb7B12 alloys. Special attention has been focused on the study of the response of these alloys to the heat treatment under an applied magnetic field. We have shown that in the (FeCo)81Nb7B12 alloy, which contains Fe and Co magnetic atoms in equal concentration, the heat treatment under longitudinal magnetic field of 20 kAm−1 is accompanied by a marked improvement of the soft magnetic properties. On the other hand, the field-annealing effect in the Co-free alloy is negligible. This observation suggests that the phenomenon of field-annealing induced anisotropy in these alloys can be explained in terms of magnetic atom pairs ordering mechanism.