External influence on the FINEMET nanocrystals

Mössbauer spectroscopy was used to study the changes induced by preparation, irradiation and mechanical grinding of nanocrystalline Fe-Nb-Cu-Si-B alloy. Mössbauer parameters of the nanocrystalline alloy differed when the sample was prepared in a vacuum or argon atmosphere. Isothermal heating has an influence on the creation of crystalline phase and orientation of net magnetic moment. Neutron irradiation amorphised the crystalline component and modified the amorphous rest. After mechanical grinding, mainly the amorphous rest was modified for irradiated as well as non-irradiated samples. We supposed that in the powdered samples the surface domains play a decisive role by their influence on the reorientation of the magnetic moments.