US 11,837,391 B2
Sintered R2M17 magnet and method of fabricating a R2M17 magnet
Kaan Üstüner, Gründau-Lieblos (DE); Matthias Katter, Alzenau (DE); and Christoph Brombacher, Wiesbaden (DE)
Assigned to Vacuumschmelze GmbH & Co. KG, Hanau (DE)
Filed by Vacuumschmelze GmbH & Co. KG, Hanau (DE)
Filed on Jul. 26, 2022, as Appl. No. 17/873,213.
Application 17/873,213 is a division of application No. 16/865,982, filed on May 4, 2020, granted, now 11,456,095.
Claims priority of application No. 1907162 (GB), filed on May 21, 2019.
Prior Publication US 2022/0406497 A1, Dec. 22, 2022
Int. Cl. H01F 1/055 (2006.01); H01F 7/02 (2006.01); H01F 1/053 (2006.01); H01F 41/22 (2006.01)
CPC H01F 1/0557 (2013.01) [H01F 1/0536 (2013.01); H01F 7/0205 (2013.01); H01F 41/22 (2013.01)] 10 Claims
OG exemplary drawing
 
1. A sintered R2M17 magnet, comprising: at least 70 vol % of a R2M17 phase, wherein R is at least one selected from the group consisting of Ce, La, Nd, Pr, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yt, Lu and Y, and M comprises Co, Fe, Cu and Zr, wherein, in an area of the R2M17 sintered magnet of ≥200 by 200 μm viewed in a Kerr micrograph, an areal proportion of demagnetised regions after application of an internal opposing field of 1200 kA/m is less than 5%.