US 12,406,785 B2
Anisotropic rare earth sintered magnet and method for producing the same
Tadao Nomura, Fukui (JP); Kazuki Otsuka, Echizen (JP); and Masayuki Kamata, Tsuruga (JP)
Assigned to SHIN-ETSU CHEMICAL CO., LTD., Tokyo (JP)
Filed by SHIN-ETSU CHEMICAL CO., LTD., Tokyo (JP)
Filed on Apr. 29, 2022, as Appl. No. 17/733,191.
Claims priority of application No. 2021-082977 (JP), filed on May 17, 2021.
Prior Publication US 2022/0367092 A1, Nov. 17, 2022
Int. Cl. H01F 1/059 (2006.01); B22F 3/16 (2006.01); B22F 3/24 (2006.01); C01B 32/907 (2017.01); C22C 38/10 (2006.01); C22C 38/12 (2006.01); C22C 38/14 (2006.01); C22C 38/16 (2006.01); C22C 38/20 (2006.01); C22C 38/22 (2006.01); C22C 38/24 (2006.01); C22C 38/26 (2006.01); C22C 38/28 (2006.01); C22C 38/30 (2006.01); C22C 38/40 (2006.01); C22C 38/44 (2006.01); C22C 38/46 (2006.01); C22C 38/48 (2006.01); C22C 38/50 (2006.01); C22C 38/52 (2006.01); H01F 1/053 (2006.01); H01F 1/055 (2006.01); H01F 1/08 (2006.01); H01F 41/02 (2006.01)
CPC H01F 1/0593 (2013.01) [B22F 3/16 (2013.01); B22F 3/24 (2013.01); C01B 32/907 (2017.08); C22C 38/10 (2013.01); C22C 38/105 (2013.01); C22C 38/12 (2013.01); C22C 38/14 (2013.01); C22C 38/16 (2013.01); C22C 38/20 (2013.01); C22C 38/22 (2013.01); C22C 38/24 (2013.01); C22C 38/26 (2013.01); C22C 38/28 (2013.01); C22C 38/30 (2013.01); C22C 38/40 (2013.01); C22C 38/44 (2013.01); C22C 38/46 (2013.01); C22C 38/48 (2013.01); C22C 38/50 (2013.01); C22C 38/52 (2013.01); H01F 1/0536 (2013.01); H01F 1/0557 (2013.01); H01F 1/086 (2013.01); H01F 41/0266 (2013.01); H01F 41/0273 (2013.01); B22F 2003/248 (2013.01); B22F 2202/05 (2013.01); C01P 2006/42 (2013.01)] 12 Claims
 
1. An anisotropic rare earth sintered magnet having a composition of a formula (R1-aZra)v(Fe1-bCOb)100-v-w-x-y(M11-cM2c)wOxCy where R is one or more kinds selected from rare earth elements and indispensably includes Sm, M1 is one or more kinds of elements selected from the group consisting of V, Cr, Mn, Ni, Ga, Al, and Si, M2 is one or more kinds of elements selected from the group consisting of Ti, Nb, Mo, Hf, Ta, and W, and v, w, x, y, a, b, and c each satisfy 7≤v≤15 at %, 4≤w≤20 at %, 0.2≤x≤4 at %, 0.2≤y≤2 at %, 0≤a≤0.2, 0≤b≤0.5, and 0≤c≤0.9, which contains a main phase of a ThMn12-type crystal compound in an amount of 80% by volume or more with the average crystal particle diameter of the main phase being 1 μm or more, which contains an R oxycarbide in the grain boundary area, and which has a density of 7.3 g/cm3 or more, and the amount of the oxycarbide in the rare earth sintered magnet being 1.7% by volume or more, wherein the anisotropic rare earth sintered magnet does not comprise Cu and does not comprise Zn.