IP Library Granted Patent US 8,152,936
Granted Patent B2
US 8,152,936 · App. 12/666,909 · Granted Apr 10, 2012

Rare earth magnet

Assignee: TDK Corporation
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Quick Facts
Patent No.
US 8,152,936
App. No.
12/666,909
Granted
Apr 10, 2012
Kind
B2
Abstract

There is provided a rare earth magnet with excellent Br and HcJ values. The rare earth magnet according to a preferred embodiment of the invention is characterized by being composed mainly of R (where R is at least one element selected from among rare earth elements including Y), B, Al, Cu, Zr, Co, O, C and Fe, wherein the content of each element is R: 25-34 wt %, B: 0.85-0.98 wt %, Al: 0.03-0.3 wt %, Cu: 0.01-0.15 wt %, Zr: 0.03-0.25 wt %, Co: ≦3 wt % (but not 0 wt %), O: ≦0.2 wt %, C: 0.03-0.15 wt % and Fe: remainder.

Claims (25)

1. A rare earth including a main phase magnet characterized by being composed mainly of R (where R is at least one element selected from among rare earth elements including Y, and R includes Nd and Dy as an essential element), B, Al, Cu, Zr, Co, O, C and Fe,

wherein the content of each element is as follows:

R: 25-34 wt % (where Dy content is 0.1-8 wt %)

B: 0.85-0.98 wt %

Al: 0.03-0.3 wt %

Cu: 0.03-0.11 wt %

Zr: 0.03-0.25 wt %

Co: ≦3 wt % (but not 0 wt %)

O: 0.03-0.1 wt %

C: 0.03-0.15 wt %

Fe: remainder.

2. A rare earth including a main phase magnet characterized by being composed mainly of R (where R is at least one element selected from among rare earth elements including Y, and R includes Nd and Dy as an essential component), B, Al, Cu, Zr, Co, O, C, Fe and Ga,

wherein the content of each element is as follows:

R: 25-34 wt % (where Dy content is 0.1-8 wt %)

B: 0.85-0.98 wt %

Al: 0.03-0.3 wt %

Cu: 0.03-0.11 wt %

Zr: 0.03-0.25 wt %

Co: ≦3 wt % (but not 0 wt %)

O: 0.03-0.1 wt %

C: 0.03-0.15 wt %

Ga: ≦0.2 wt % (but not 0 wt %)

Fe: remainder.

3. A rare earth magnet according to claim 1 , having a core-shell structure wherein the area near the outer periphery of the main phase is a phase with a high Dy content while the interior is a phase with a low Dy content.

4. A rare earth magnet according to claim 2 , having a core-shell structure wherein the area near the outer periphery of the main phase is a phase with a high Dy content while the interior is a phase with a low Dy content.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Dec 28, 2009
From: TSUBOKURA, TAEKO; IWASAKI, MAKOTO; NAKANE, MAKOTO; BABA, FUMITAKA
To: TDK CORPORATION
Reel/Frame 023709/0269 →
Priority Claims (1)
JP 2007-172789 · Jun 29, 2007 · national
Continuity (1)
Related Publication 20100233016A1 · Sep 16, 2010