US 12,435,398 B2
Metal magnetic particle, inductor, method for manufacturing metal magnetic particle, and method for manufacturing metal magnetic core
Takuya Ishida, Nagaokakyo (JP); Makoto Yamamoto, Nagaokakyo (JP); Katsutoshi Uji, Nagaokakyo (JP); Yuya Ishida, Nagaokakyo (JP); and Mitsuru Odahara, Nagaokakyo (JP)
Assigned to Murata Manufacturing Co., Ltd., Kyoto-fu (JP)
Filed by Murata Manufacturing Co., Ltd., Kyoto-fu (JP)
Filed on Feb. 21, 2024, as Appl. No. 18/583,595.
Application 18/583,595 is a division of application No. 17/201,871, filed on Mar. 15, 2021, granted, now 11,965,229.
Claims priority of application No. 2020-058366 (JP), filed on Mar. 27, 2020.
Prior Publication US 2024/0191328 A1, Jun. 13, 2024
Int. Cl. H01F 1/147 (2006.01); B22F 1/145 (2022.01); B22F 1/16 (2022.01); B22F 3/02 (2006.01); C22C 38/02 (2006.01); H01F 1/20 (2006.01); H01F 1/24 (2006.01); H01F 1/33 (2006.01); B22F 1/107 (2022.01); H01F 27/255 (2006.01)
CPC C22C 38/02 (2013.01) [B22F 1/145 (2022.01); B22F 1/16 (2022.01); B22F 3/02 (2013.01); H01F 1/14766 (2013.01); H01F 1/24 (2013.01); B22F 1/107 (2022.01); B22F 2301/35 (2013.01); B22F 2302/256 (2013.01); C22C 2202/02 (2013.01); H01F 27/255 (2013.01); Y10T 428/12181 (2015.01)] 13 Claims
OG exemplary drawing
 
1. A method for manufacturing a metal magnetic particle, the method comprising:
mixing a raw material particle having, on a surface of an alloy particle containing Fe and Si, a Si oxide film and an Fe oxide film from a side of the alloy particle with Si alkoxide and alcohol;
forming a coating film forming particle formed with a coating film containing silicon oxide by hydrolyzing and drying the Si alkoxide; and
forming an oxide layer on the surface of the alloy particle by performing heat treatment on the coating film forming particle in an oxidizing atmosphere, wherein
an average thickness of the coating film is from 10 nm to 14 nm,
a layer in which Fe content takes a local maximum value is formed over a layer in which Si content takes a local maximum value and the layer in which Fe content takes the local maximum value also includes Si, and
in the layer in which Si content takes the local maximum value, Si content is greater than Fe content at a point where Si content takes the local maximum value.