公开(公告)号：US20230118859A1

公开(公告)日：2023-04-20

申请号：US17911760

申请日：2021-03-29

Applicant: TDK CORPORATION

Inventor： Yoshinori FUJIKAWA ,  Reiji YAMADA

IPC: H01F1/057 ,  C22C30/02 ,  B22F9/02 ,  B22F3/16

Abstract: An R-T-B-based permanent magnet which contains R that represents at least one rare earth element essentially including Tb or Dy, T that represents Fe or at least one iron-group element essentially including Fe and Co, and B that represents boron, and further contains Cu. The total content of R is 28.35 to 29.95% by mass, inclusive, the content of Cu is 0.05 to 0.40% by mass, inclusive, and the content of B is 0.93 to 1.00% by mass, inclusive. The distribution of the concentration of Tb or Dy decreases from the outside of the R-T-B-based permanent magnet toward the inside of the R-T-B-based permanent magnet.