Novel Fe-based nanocrystalline powder cores with high performance prepared by using industrial materials

The FeSiBPNbCu amorphous magnetic powder with partial crystallization is successfully synthesized using low purity industrial raw materials by gas atomization. The magnetic powder cores (MPCs) are then produced from the mixture of the FeSiBPNbCu powders with 2 wt % epoxy resin as insulation and bonding materials by cold pressing under a compact pressure of 1800 MPa. Evolution of the high-frequency properties for the MPCs with respect to the annealing temperature is systematically studied. The results show that upon annealing at the optimum temperature, the cores exhibit excellent magnetic properties, including high initial permeability of 86 with a high frequency stability up to 10 MHz, high quality factor of 110 at 1 MHz, and low core loss of 1290 mW/cm3 at 100 kHz for Bm = 0.1 T. It is emphasized that the MPCs prepared by partially crystallized magnetic powders can also achieve lower core losses and higher magnetic permeability, which is of great significance in industrial production.