公开(公告)号：US11043320B2

公开(公告)日：2021-06-22

申请号：US15915901

申请日：2018-03-08

Applicant: TDK CORPORATION

Inventor： Masahiro Kamiya ,  Yasuhide Yamashita ,  Chiomi Sato ,  Yousuke Futamata ,  Ryoma Nakazawa ,  Takeshi Takahashi ,  Hiroyuki Ono

IPC: H01F1/24 ,  H01F1/33 ,  H01F3/08 ,  B22F1/02 ,  H01F41/02 ,  C22C38/02 ,  H01F1/26

Abstract: A dust core includes a metal magnetic material, a resin, and an insulation film. The insulation film contacts with a surface of the metal magnetic material and covers the metal magnetic material. The insulation film includes a first film and a second film. The first film contacts with the surface of the metal magnetic material. The second film contacts with a surface of the first film. A density of the first film is higher than a density of the second film.