US 11,657,935 B2
Iron oxide magnetic powder and manufacturing method therefor
Youn Kyoung Baek, Changwon-Si (KR); Jung Goo Lee, Busan (KR); Kyung Min Kim, Busan (KR); Young Kuk Kim, Changwon-Si (KR); and Min Ji Pyo, Changwon-Si (KR)
Assigned to KOREA INSTITUTE OF MATERIALS SCIENCE, Changwon-si (KR)
Appl. No. 17/51,979
Filed by KOREA INSTITUTE OF MACHINERY & MATERIALS, Daejeon (KR)
PCT Filed Jul. 17, 2019, PCT No. PCT/KR2019/008835
§ 371(c)(1), (2) Date Oct. 30, 2020,
PCT Pub. No. WO2020/017887, PCT Pub. Date Jan. 23, 2020.
Claims priority of application No. 10-2018-0082783 (KR), filed on Jul. 17, 2018; and application No. 10-2019-0084143 (KR), filed on Jul. 12, 2019.
Prior Publication US 2021/0241950 A1, Aug. 5, 2021
Int. Cl. H01F 1/11 (2006.01); B22F 9/08 (2006.01); B22F 1/00 (2022.01); C01G 49/06 (2006.01); B22F 1/07 (2022.01)
CPC H01F 1/11 (2013.01) [B22F 1/07 (2022.01); B22F 9/08 (2013.01); C01G 49/06 (2013.01); B22F 2302/256 (2013.01); C01P 2004/01 (2013.01); C01P 2004/64 (2013.01); C01P 2006/42 (2013.01)] 13 Claims
OG exemplary drawing
 
1. A magnetic powder, comprising:
a silica matrix; and
particles of an iron oxide embedded in the silica matrix,
wherein the particles of the iron oxide comprises particles of a hard magnetic iron oxide, and wherein the particles of the hard magnetic iron oxide are ε-Fe2O3, and
wherein a value of a full width at half-maximum (FWHM) of the ε-Fe2O3 is 0.36° to 0.53°, which results from measuring a diffraction peak of a {122} plane as a main peak of a crystal phase of the ε-Fe2O3.