Method for manufacturing rare earth sintered magnet
AssigneeShin-Etsu Chemical Co., Ltd.
InventorsAkira Yamada, Tetsuya Ohashi, Koichi Hirota
Life of this patent
Estimating the term…
Abstract
A rare earth sintered magnet is manufactured by preparing a R1-T-X sintered body having a major phase of R12T14X composition wherein R1 is a rare earth element(s) and essentially contains Pr and/or Nd, T is Fe, Co, Al, Ga, and/or Cu, and essentially contains Fe, and X is boron and/or carbon, forming an alloy powder containing 5≤R2≤60, 5≤M≤70, and 20<B≤70, in at %, wherein R2 is a rare earth element(s) and essentially contains Dy and/or Tb, M is Fe, Cu, Al, Co, Mn, Ni, Sn, and/or Si, and B is boron, disposing the alloy powder on the sintered body, and heat treating the alloy-covered sintered body.
Claims26
A method for manufacturing a rare earth sintered magnet comprising the steps of:
- preparing a plurality of R1-T-X sintered bodies each having a major phase of R12T14X composition wherein R1 is at least one element selected from rare earth elements, and wherein at least one R1 group is Pr or Nd, T is selected from the group consisting of Fe, Co, Al, Ga, and Cu, and wherein at least one T group is Fe, and X is boron and/or carbon, and wherein the plurality of R1-T-X sintered bodies each contains 60 to 99% by volume of the R12T14X composition as the major phase,
- forming an alloy powder, which is formed of an alloy containing R2, M and B wherein R2 is at least one element selected from rare earth elements, and wherein at least one R2 group is Dy or Tb, M is at least one element selected from the group consisting of Fe, Cu, Al, Co, Mn, Ni, Sn and Si, and B is boron, the alloy containing 5 to 60 at % of R2, 5 to 70 at % of M, and from more than 20 at % to 70 at % of B,
- disposing the alloy powder on the surface of each of the plurality of sintered bodies to obtain a plurality of alloy-covered sintered bodies,
- laminate the plurality of alloy-covered sintered bodies to form a laminate,
- heat treating the laminate in vacuum or inert gas atmosphere at a temperature not higher than a sintering temperature of the plurality of sintered bodies, and
- separating each of the alloy-covered sintered bodies from the laminate.
A method for manufacturing a rare earth sintered magnet comprising the steps of:
- preparing a plurality of R1-T-X sintered bodies each having a major phase of R12T14X composition wherein R1 is at least one element selected from Pr and Nd, T is Fe, and X is at least one element selected from boron and carbon, and wherein the plurality of R1-T-X sintered bodies each contains 60 to 99% by volume of the R12T14X composition as the major phase,
- forming an alloy powder, which is formed of an alloy containing R2, M and B wherein R2 is at least one element selected from Dy and Tb, M is at least one element selected from the group consisting of Fe, Cu, Al, Co, Mn, Ni, Sn and Si, and B is boron, the alloy containing 5 to 60 at % of R2, 5 to 70 at % of M, and from more than 20 at % to 70 at % of B,
- disposing the alloy powder on the surface of each of the plurality of the sintered bodies to obtain a plurality of alloy-covered sintered bodies,
- laminate the plurality of alloy-covered sintered bodies to form a laminate,
- heat treating the laminate in vacuum or inert gas atmosphere at 600° C. to 1100° C., and
- separating each of the alloy-covered sintered bodies from the laminate.
Dependencies are inferred from the claim text.