Process for forming insulating layers on soft magnetic powder composite core from magnetic particles

摘要

The present invention provides a soft magnetic powder composite core for an electric apparatus produced with soft magnetic particles having electric insulating layers on the surfaces thereof, wherein said electric insulating layers are formed by mixing said soft magnetic particles with an insulating layer-forming solution which comprises a phosphating solution and a rust inhibitor, which is an organic compound containing at least one of nitrogen or sulfur having a lone pair of electrons suppressing the formation of iron oxide and surfactant, and drying the treated soft magnetic particles at a predetermined temperature. The soft magnetic powder composite core is excellent in iron loss and magnetic flux density.