NEWLY-DEVELOPED AND CHEAP NANOCRYSTALLINE Fe-Cu-Nb-Mo-Si-B ALLOYS FOR SWITCHING MODE POWER SUPPLY

The synthetical soft magnetic properties are reported for newly-developed nanocrystalline Fe73.5 Cu1 Nb0.9Mo2.1 Si13.5 B9 and Fe73.5 Cu1 Nb0.5Mo2.5Si13.5B9 alloys. The levels of high-frequency losses of the new alloys are P3/100k=612 and 670 kWm-3,P2/200k=880 and 973 kWm-3, P2/500k=4300 and 4600 kWm-3, P0.5/1000k=860 and 920 kWm-3, respectively. They are significantly lower than those of the superior power Mn-Zn ferrite H7c.4.The dependences of core loss on frequency and amplitude flux density have been analysed. The practical applications of the new alloys to switching mode power supplies with the output power of 1 and 2 kW are reported.