Microstructure and some magnetic properties of amorphous and nanocrystalline Fe–Cu–Nb–Si–B alloys

The microstructure and magnetic properties, i.e. saturation magnetic polarization, initial magnetic susceptibility and its disaccommodation, for the amorphous and the partially crystallized Fe73.5Cu1Nb3Si13.5B9 ribbons aged at 733 K were studied. After accumulative annealing of the samples at 733 K, the decrease of the initial susceptibility and increase of the disaccommodation intensities were observed. These are connected with the annealing out of ‘free volumes’ in the amorphous matrix, which is the main source of the magnetic after-effect in all investigated samples.