US 12,205,738 B2
Method of producing sintered magnet
Tae Hoon Kim, Daejeon (KR); Soon Jae Kwon, Daejeon (KR); Hyounsoo Uh, Daejeon (KR); Ikjin Choi, Daejeon (KR); Jinhyeok Choe, Daejeon (KR); Ingyu Kim, Daejeon (KR); Eunjeong Shin, Daejeon (KR); and Nakheon Sung, Daejeon (KR)
Assigned to LG Chem, Ltd., Seoul (KR)
Appl. No. 17/635,801
Filed by LG Chem, Ltd., Seoul (KR)
PCT Filed Oct. 7, 2020, PCT No. PCT/KR2020/013643
§ 371(c)(1), (2) Date Feb. 16, 2022,
PCT Pub. No. WO2021/071236, PCT Pub. Date Apr. 15, 2021.
Claims priority of application No. 10-2019-0123870 (KR), filed on Oct. 7, 2019.
Prior Publication US 2022/0310292 A1, Sep. 29, 2022
Int. Cl. H01F 1/057 (2006.01); B22F 3/10 (2006.01); B22F 3/24 (2006.01); B22F 3/26 (2006.01); C22C 1/04 (2023.01); C22C 28/00 (2006.01); C22C 38/00 (2006.01); C22C 38/06 (2006.01); C22C 38/10 (2006.01); C22C 38/16 (2006.01); H01F 41/02 (2006.01)
CPC H01F 1/0577 (2013.01) [B22F 3/10 (2013.01); B22F 3/26 (2013.01); C22C 1/04 (2013.01); C22C 28/00 (2013.01); C22C 38/005 (2013.01); C22C 38/06 (2013.01); C22C 38/10 (2013.01); C22C 38/16 (2013.01); H01F 41/0253 (2013.01); B22F 2003/248 (2013.01); B22F 2301/355 (2013.01); B22F 2301/45 (2013.01); C22C 2202/02 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A method of producing a sintered magnet comprising:
sintering an R—Fe—B based magnetic powder to produce a sintered magnet;
mixing PrH2, Al, Cu and Ga to produce a eutectic alloy mixture;
pressing the eutectic alloy mixture by a cold isostatic pressing method;
heating the pressed eutectic alloy mixture to produce a eutectic alloy;
infiltrating the eutectic alloy into the sintered magnet,
wherein the eutectic alloy contains Pr, Al, Cu and Ga,
wherein R in the R—Fe—B based magnetic powder is Nd, Pr, Dy, Ce or Tb, and
wherein infiltrating the eutectic alloy comprises:
applying the eutectic alloy to the sintered magnet; and
heat-treating the sintered magnet to which the eutectic alloy is applied.