Title:
RAW MATERIAL ALLOY FOR R-T-B-BASED MAGNET
Document Type and Number:
WIPO Patent Application WO/2014/174795
Kind Code:
A1
Abstract:
A raw material alloy for a R-T-B-based magnet (wherein R represents at least one of rare earth elements including Y; and T represents at least one of transition elements including Fe as the essential element), said alloy containing a R2T14B phase as the main phase and R-rich phases in each of which R is concentrated, wherein the distance between the R-rich phases is 10 μm or more and the ellipsoidal aspect ratio of each of the R-rich phases is 0.6 or more. A fine powder produced by milling the raw material alloy has excellent fluidability, and enables the production of a sintered magnet having a complicated shape. When the raw material alloy for a R-T-B-based magnet contains Dy and/or Tb as R, it is desirable that the percentage ratio (A/B) produced by dividing the total concentration (A) of Dy and Tb in the main phase by the total concentration (B) of Dy and Tb in each of the R-rich phases is 180% or more. It is also desirable that the percentage ratio (D/C) produced by dividing the concentration (D) of an impurity in each of the R-rich phases by the concentration (C) of the impurity in the main phase is 230% or more.
Inventors:
SHIMIZU TAKAYUKI (JP)
Application Number:
PCT/JP2014/002123
Publication Date:
October 30, 2014
Filing Date:
April 15, 2014
Export Citation:
Assignee:
CHUO DENKI KOGYO CO LTD (JP)
International Classes:
C22C38/00; B22F1/00; B22F9/08; C22C33/02; H01F1/057; H01F1/06
Foreign References:
| JP2011199069A | 2011-10-06 | |||
| JP2008058323A | 2008-03-13 | |||
| JPH08264363A | 1996-10-11 | |||
| JPH08176755A | 1996-07-09 | |||
| JP2013111599A | 2013-06-10 |
Attorney, Agent or Firm:
M. MORI PATENT FIRM (JP)
Patent business corporation Woods Michio patent firm (JP)
Patent business corporation Woods Michio patent firm (JP)
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