| (19) |
 |
|
(11) |
EP 0 255 939 A3 |
| (12) |
EUROPEAN PATENT APPLICATION |
| (88) |
Date of publication A3: |
|
31.05.1989 Bulletin 1989/22 |
| (43) |
Date of publication A2: |
|
17.02.1988 Bulletin 1988/07 |
| (22) |
Date of filing: 04.08.1987 |
|
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| (84) |
Designated Contracting States: |
|
AT BE CH DE FR GB IT LI NL SE |
| (30) |
Priority: |
04.08.1986 JP 182998/86
29.08.1986 US 901736
|
| (71) |
Applicant: SUMITOMO SPECIAL METALS CO., LTD. |
|
Osaka (JP) |
|
| (72) |
Inventors: |
|
- Fujimura, Setsuo
Sumitomo Special Metals Co.,Ltd.
Shimamoto-cho
Mishima-gun
Osaka-fu (JP)
- Sagawa, Masato
Sumitomo Special Metals Co.,Ltd.
Shimamoto-cho
Mishima-gun
Osaka-fu (JP)
- Yamamoto, Hitoshi
Sumitomo Special Metals Co.,Ltd
Shimamoto-cho
Mishima-gun
Osaka-fu (JP)
- Hirosawa, Satoshi
Sumitomo Special Metals Co.,Ltd
Shimamoto-cho
Mishima-gun
Osaka-fu (JP)
|
| (74) |
Representative: Diehl, Hermann O. Th., Dr. et al |
|
Diehl, Glaeser, Hiltl & Partner
Patentanwälte
Postfach 19 03 65
80603 München
80603 München (DE) |
|
| |
|
| (54) |
Rare earth magnet and rare earth magnet alloy powder having high corrosion resistance |
(57) An (Fe,Co)-B-R tetragonal type magnet and magnet alloy powder having a high corrosion
resistance, which have a boundary phase stabilized by Co and Al against corrosion,
and which consist essentially of:
0.2 - 3.0 at% Dy and 12 - 17 at% of the sum of Nd and Dy;
5 - 10 at% B;
0.5 - 13 at% Co;
0.5 - 4 at% Al; and
the balance being at least 65 at% Fe.
0.1 - 1.0 at% of Ti and/or Nb may be present. The alloy powders can be stabilized.