Soft magnetic composite materials have now become the major development direction of magnetic core materials for high-frequency electronic transformers. Compared with traditional soft ferrites and soft magnetic alloys, magnetic metal particles or films can be distributed in non-conductors and other materials. , So that the high-frequency loss is significantly reduced, while increasing the operating frequency. Its processing technology can not only be processed into powder core by hot pressing method, but also can use current plastic engineering technology to inject into complex shape magnetic core, which has smaller density, lighter weight, improved production efficiency, reduced cost, and repeated products. Features such as good sex and consistency. Moreover, different ratios can be used to change the magnetic properties. An example of a composite material composed of soft ferrite and permalloy is introduced. Now a soft magnetic composite powder core with an operating frequency of 10kHz or more has been developed, which can replace soft ferrite in high-frequency filter inductors.