R-T-B system permanent magnet and plating film
AssigneeTDK Corporation
InventorsYasuyuki Nakayama, Kazuhito Yamasawa
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Abstract
It is an object of the present invention to provide an R—T—B system permanent magnet which is easy to apply in the production of an actual R—T—B system permanent magnet, and which contains a plating film that is also effective in securing hardness. The present invention achieves this object by providing an R—T—B system permanent magnet 1 which contains a magnet base body 2 constituted from a sintered body which contains at least main phase grains containing an R2T14B compound, and a grain boundary phase which contains a larger amount of R than the main phase grains, and a plating film 3 which covers the magnet base body 2 surface and which contains, when C content is defined as Cc (wt. %), 0.005<Cc≦0.2 wt. %.
Claims14
An R—T—B system permanent magnet comprising:
- a magnet base body constituted from a sintered body which comprises at least main phase grains comprising an R2T14B compound, and a grain boundary phase which comprises a larger amount of R than the main phase grains;
- and
- a plating film which covers the magnet base body surface and which comprises, when a C content is defined as Cc (wt. 0.005<Cc≦0.2 wt. %;
- wherein
- R represents one or more rare earth element s , and T represents one or more transition metal elements comprising Fe, or Fe and Co as essential components.
A plating film, which covers over a substrate for corrosion resistance improvement, and which comprises 0.005<Cc≦0.2 wt. % when C content is defined as Cc (wt. %).
Dependencies are inferred from the claim text.