Title:
HIGH CORROSION-RESISTANT R-Fe-B-BASE BONDED MAGNET AND METHOD OF MANUFACTURING THE SAME
Document Type and Number:
WIPO Patent Application WO/1999/023675
Kind Code:
A1
Abstract:
A method of efficiently manufacturing R-Fe-B-base bonded magnets of various shapes such as ring shape and disk shape having a high corrosion resistance and capable of being plated electrically with ease, wherein the corrosion resistance of the magnet is improved by forming a conductive film of a metal on the surface thereof with tight adhesion, uniformity and efficiency. The method comprises filling the holes of the magnet with polishing powder, inorganic powder and polishing chips, fixing these materials in the holes by fat of a vegetable medium and sealing the resultant holes, and barrel-polishing the magnet by a barrel unit in the dry process with indefinitely shaped, i.e. spherical, massive or acicular (wiry) pieces of a required size of Cu, Sn, Zn, Pb, Cd, In, Au, Ag, Fe, Ni, Co, Cr and Al and such pieces of alloys thereof used as a metallic medium. Said fine pieces of metals such as Cu are press fitted into a resin surface and holes of the bonded magnet and cover the surface and holes and further, cover the surfaces of particles of magnetic powder whereby a very uniform conductive film can be formed on the surface of the bonded magnet, so that it becomes possible to subject the bonded magnet to electric plating excellently and obtain a plated R-Fe-B-base bonded magnet of a high corrosion resistance and with minimum deterioration of the magnetic properties.
Inventors:
YOSHIMURA KOHSHI (JP)
NISHIUCHI TAKESHI (JP)
KIKUI FUMIAKI (JP)
ISOZAKI TAKAHIRO (JP)
NISHIUCHI TAKESHI (JP)
KIKUI FUMIAKI (JP)
ISOZAKI TAKAHIRO (JP)
Application Number:
PCT/JP1998/004829
Publication Date:
May 14, 1999
Filing Date:
October 23, 1998
Export Citation:
Assignee:
SUMITOMO SPEC METALS (JP)
YOSHIMURA KOHSHI (JP)
NISHIUCHI TAKESHI (JP)
KIKUI FUMIAKI (JP)
ISOZAKI TAKAHIRO (JP)
YOSHIMURA KOHSHI (JP)
NISHIUCHI TAKESHI (JP)
KIKUI FUMIAKI (JP)
ISOZAKI TAKAHIRO (JP)
International Classes:
C25D3/56; C25D5/34; (IPC1-7): H01F7/02
Foreign References:
| JPS62290107A | 1987-12-17 | |||
| JPH08250356A | 1996-09-27 |
Other References:
See also references of EP 1028437A4
Attorney, Agent or Firm:
Oshida, Yoshihisa (Ginza 3-chome Chuou-ku Tokyo, JP)
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