Title:
R-FE-B-BASED SINTERED MAGNET
Document Type and Number:
WIPO Patent Application WO/2021/095633
Kind Code:
A1
Abstract:
The purpose of the present invention is to achieve both of a high remanent magnetic flux density and high coercivity which have been heretofore believed to be ambivalent properties to each other. Provided is an R-Fe-B-based sintered magnet which has a composition comprising R (wherein R represents at least one element selected from rare earth elements, and essentially contains Nd), B, M (wherein M represents at least one element selected from Si, Al, Mn, Ni, Co, Cu, Zn, Ga, Ge, Pd, Ag, Cd, In, Sn, Sb, Pt, Au, Hg, Pb and Bi), X (wherein X represents at least one element selected from Ti, Zr, Hf, Nb, V and Ta) and C, with a remainder comprising Fe, O and unavoidable impurities, and has a main phase comprising R2Fe14B and a grain boundary phase comprising an R-C phase having a higher R concentration and a higher C concentration than those in the main phase, the R-Fe-B-based sintered magnet being characterized in that the area ratio of the R-C phase in a cross section of the magnet is more than 0% and 0.5% or less.
Inventors:
YOSHINARI AKIHIRO (JP)
IIDA HIROKI (JP)
HIROTA KOICHI (JP)
YOSHIDA MIKIO (JP)
IIDA HIROKI (JP)
HIROTA KOICHI (JP)
YOSHIDA MIKIO (JP)
Application Number:
PCT/JP2020/041346
Publication Date:
May 20, 2021
Filing Date:
November 05, 2020
Export Citation:
Assignee:
SHINETSU CHEMICAL CO (JP)
International Classes:
H01F1/057; B22F3/00; C22C33/02; C22C38/00
Domestic Patent References:
| WO2009004994A1 | 2009-01-08 | |||
| WO2013122255A1 | 2013-08-22 | |||
| WO2013191276A1 | 2013-12-27 | |||
| WO2004081954A1 | 2004-09-23 |
Foreign References:
| JP2009260338A | 2009-11-05 | |||
| JPH0931608A | 1997-02-04 | |||
| JPH04330702A | 1992-11-18 | |||
| JPH04184901A | 1992-07-01 | |||
| JP2016143828A | 2016-08-08 |
Other References:
See also references of EP 4060690A4
Attorney, Agent or Firm:
PATENT PROFESSIONAL CORPORATION EI-MEI PATENT OFFICE (JP)
Download PDF: