Patent ID: 8241518
Filing Date: 2012-08-14
Classification: B22F,C22C,H01F

Abstract:
1. A dust core comprising: a plurality of composite magnetic particles including a metal magnetic particle of pure iron and an insulating film surrounding a surface of said metal magnetic particle and containing a phosphate; an aromatic polyetheretherketone resin; and a metallic soap and/or an inorganic lubricant having a hexagonal crystal structure, said metallic soap and said inorganic lubricant being particles with an average particle size of not more than 2.0 μm, wherein content of said metallic soap and/or said inorganic lubricant having a hexagonal crystal structure is not less than 0.001% by mass and not more than 0.05% by mass relative to said plurality of composite magnetic particles, said aromatic polyetheretherketone resin has a weight average molecular weight of not less than 10000 and not more than 100000, said aromatic polyetheretherketone resin has an average particle size that is not less than 10 times as large as the average particle size of said metallic soap and/or said inorganic lubricant having a hexagonal crystal structure and that is not more than twice as large as an average particle size of said metal magnetic particle, and said dust core has a flexural strength at 200° C. of not less than 109.3 MPa.