Temperature dependence of magnetic properties in Fe-Co and Fe-Cr base nanocrystalline alloys

The temperature dependence of the magnetic properties (i.e., ac magnetic permeability and magnetoimpedance voltage) is analyzed for Fe-Co and Fe-Cr base nanocrystalline materials. Around the Curie point of the residual amorphous matrix a magnetic transition is detected, associated with the magnetic decoupling of ferromagnetic crystallites. The magnetic nature of such magnetic transition is analyzed within the framework of the random anisotropy model, taking into account the basic structural and magnetic characteristics of the constituent magnetic phases.