Method for manufacturing composite metal powder soft magnetic core with excellent DC overlapping characteristics

摘要

BACKGROUND OF THE INVENTION 1. Field of the Invention [0002] The present invention is a composite inductor of soft metal cores with excellent DC overlapping characteristics used in choke coils for suppressing or smoothing electronic noise, mainly as an inductor of secondary DC circuit of Switching Mode Power Supply (SMPS). A method comprising preparing a sendust alloy powder composed of 7 to 13% Si, 3 to 9% Al, and a residual amount of Fe, comprising 45 to 55% Ni and a residual amount of Fe having a high ductility and a high permeability. 1 to 50% of the alloy (Permalloy) powder and Molly Permalloy powder (MPP) are added and mixed at a total weight ratio to prepare a composite metal powder. Then, the obtained composite metal powder is insulated coated with a mixed ceramic and a lubricant is added. After mixing, it is molded into a core and manufactured by heat-treating the molded core.;The soft magnetic core manufactured through the present invention can lower the molding pressure by plastic deformation of the soft metal during molding, thereby extending the life of the mold, and reducing the empty space in the core and damaging the ceramic insulating layer by reducing the molding lubricant. By minimizing the frequency, it provides excellent high frequency characteristics and shows very good DC overlapping characteristics at large currents essential for smooth choke cores for switching power supplies (SMPS).