COEXISTENCE OF VARIOUS MAGNETIC PHASES IN NANOCRYSTALLINE FE-BASED METALLIC GLASSES

It is shown that, besides the promising prospects of applications, nanocrystalline Fe-based metallic glasses (nominal composition Fe73.5Cu1Nb3Si13.5B9) are interesting objects for basic research because of the variety of magnetic phases which they can show at elevated temperatures. These unusual particulate media show ferromagnetic behavior for temperatures below the Curie point of the residual amorphous matrix, however, in the temperature range above this point they may display superferromagnetic or superparamagnetic properties depending on the size and volumetric fraction of the nanoparticles created within the material by the appropriate annealing. The results of a number of experiments are presented, which show that all the magnetic phases mentioned above can be created in the nanocrystalline material considered.