AN INVESTIGATION OF MAGNETIC-PROPERTIES OF FE73.5CU1NB3SI13.5B9 ALLOYS

The magnetic phase transition of a rapidly quenched Fe73.5Cu1Nb3Si13.5B9 alloy has been investigated by two different techniques: differential scanning calorimetry (DSC), and thermogravimetry analysis (TGA) under a magnetic field. The DSC measurement showed two distinct exothermic peaks during the crystallization process and a detectable peak at the amorphous Curie transition temperature (T(c) = 325-degrees-C). These results were in good agreement with those measured by TGA under a magnetic field. In addition, the TGA measurements showed the Curie phase transition of the nanocrystalline structure at 570-degrees-C. After the nanocrystalline structure was fully developed, the relationship between the core loss at 10 kHz and temperature was established at two different magnetic induction levels. There was a minimum of the core loss at certain temperatures, which decreased with increasing magnetic induction.