Metal treatment – Stock – Magnetic
Reexamination Certificate
2007-01-12
2009-08-04
Sheehan, John P. (Department: 1793)
Metal treatment
Stock
Magnetic
C075S244000
Reexamination Certificate
active
07569114
ABSTRACT:
The object of the present invention is to provide a rare earth magnet which enables to achieve a good balance between high coercive force and high residual magnetic flux density, and its manufacturing method. The present invention provides a rare earth magnet in which a layered grain boundary phase is formed on a surface or a potion of a grain boundary of Nd2Fe14B which is a main phase of an R—Fe—B (R is a rare-earth element) based magnet, and wherein the grain boundary phase contains a fluoride compound, and wherein a thickness of the fluoride compound is 10 μm or less, or a thickness of the fluoride compound is from 0.1 μm to 10 μm, and wherein the coverage of the fluoride compound over a main phase particle is 50% or more on average. Moreover, after layering fluoride compound powder, which is formed in plate-like shape, in the grain boundary phase, the rare earth magnet is manufactured by quenching the layered compound after melting it at a vacuum atmosphere at a predetermined temperature, or by heating and pressing the main phase and the fluoride compound to make the fluoride compound into a layered fluoride compound along the grain boundary phase.
REFERENCES:
patent: 4747924 (1988-05-01), Itoh et al.
patent: 5411603 (1995-05-01), Vial et al.
patent: 5858124 (1999-01-01), Endo et al.
patent: 6511552 (2003-01-01), Makita et al.
patent: 6960240 (2005-11-01), Hirota et al.
patent: 2003/0106615 (2003-06-01), Hirota et al.
patent: 2005/0081959 (2005-04-01), Kim et al.
patent: 1234589 (1999-11-01), None
patent: 61-195954 (1986-08-01), None
patent: 2003-282312 (2003-10-01), None
patent: WO 2005/123974 (2005-12-01), None
Machine translation of Japanese Patent Document No. 2003-282312.
Chinese Official Action issued on Mar. 16, 2007, for CN 200510079130X.
Chinese Official Action issued on Nov. 30, 2007, for CN 200510079130X.
Komuro Matahiro
Satsu Yuichi
Antonelli, Terry Stout & Kraus, LLP.
Hitachi , Ltd.
Sheehan John P.
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