US 12,073,989 B2
Method for producing powder magnetic core and powder magnetic core
Yasutaka Matsumoto, Suwa (JP)
Assigned to SEIKO EPSON CORPORATION, Tokyo (JP)
Filed by SEIKO EPSON CORPORATION, Tokyo (JP)
Filed on Jan. 14, 2021, as Appl. No. 17/248,203.
Claims priority of application No. 2020-004231 (JP), filed on Jan. 15, 2020.
Prior Publication US 2021/0213524 A1, Jul. 15, 2021
Int. Cl. H01F 41/02 (2006.01); B22F 1/08 (2022.01); B22F 1/102 (2022.01); B22F 1/14 (2022.01); B22F 1/16 (2022.01); B22F 3/16 (2006.01); H01F 1/22 (2006.01)
CPC H01F 41/0246 (2013.01) [B22F 1/08 (2022.01); B22F 1/102 (2022.01); B22F 1/14 (2022.01); B22F 1/16 (2022.01); B22F 3/16 (2013.01); H01F 1/22 (2013.01); B22F 2201/03 (2013.01); B22F 2202/01 (2013.01); B22F 2202/11 (2013.01); B22F 2202/13 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A method for producing a powder magnetic core, the method comprising:
applying energy to a surface of a soft magnetic powder coated with an insulator, to cleave a portion of a molecular chain in the insulator and form a dangling bond in the insulator, wherein
the insulator includes a polyorganosiloxane compound, and
the application of the energy includes exposure of the soft magnetic powder to an ionized gas;
exposing the soft magnetic powder to an atmosphere having an atmospheric pressure dew point of −30° C. or higher and 15° C. or lower; and
forming a molded body by pressing the soft magnetic powder at 20 MPa or more and 400 MPa or less.