EFFECT OF THE HARD MAGNETIC INCLUSION ON THE MACROSCOPIC ANISOTROPY OF NANOCRYSTALLINE MAGNETIC-MATERIALS

It is shown that the presence of highly anisotropic magnetic precipitates in a soft multiphased matrix can produce a remarkable hardening, even when the volume fraction of the precipitates is small. The exchange coupling between the matrix and the precipitates is the relevant parameter. In particular, the simplified analysis we develop in this paper accounts for the magnetic hardening observed in very soft Fe-rich nanocrystals after annealing at higher temperatures.