Microscopic study of the magnetic coupling in a nanocrystalline soft magnet

The magnetic behaviour of nanosize ferromagnetic bcc granules embedded in a n amorphous tissue (i.e., partially crystallized Fe80Zr7B12Cu amorphous all oy) was studied by Fe-57 Mossbauer spectroscopy. The results are compared w ith the bulk counterparts: bcc-Fe and amorphous Fe2B0.625Zr0.375. Size depe ndent enhancement of the Curie point of the nanosize amorphous phase was no t observed. At temperatures well above the Curie point of the amorphous pha se superparamagnetic relaxation of the bcc crystallites is observed opening new possibilities to study the anisotropy energy of nanosize ferromagnetic grains.