Abstract:In this thesis, Fe-Si system metal magnetic powder core was prepared from flaky Fe95Si1B2P0.5Cu1.5 alloy powders instead of the spherical Fe-6.5%Si alloy powders. Firstly, the preparation of Fe95Si1B2P0.5Cu1.5 alloy powders and Fe95Si1B2P0.5Cu1.5 magnetic powder core were studied, and then the influences of annealing temperature and forming pressures on soft magnetic properties of the magnetic powder core were systematically investigated. Research showed that the permeability (μe) of Fe95Si1B2P0.5Cu1.5 magnetic powder core had optimal stability of frequency in the frequency range of 1~200kHz. Residual internal stress produced in the pressing process was fully released after annealing at 450℃ for 1h, which could significantly improve the permeability (μe) of the magnetic powder core, and the maximum value was 53 with a forming pressure of 1.74GPa. With the increase of the applied DC magnetic field level, the permeability of the magnetic powder core decreased gradually. When DC magnetic field levels(H) was 50Oe, the percentage permeability of the magnetic powder core remain higher than 70%, As H increase to 130Oe, the permeability of magnetic powder core was still greater than 20. This showed that Fe95Si1B2P0.5Cu1.5 magnetic power core had optimal DC-bias property.