Rare earth sintered magnet and method for production thereof

Patent metadata

Field	Value
Publication number	US-9551052-B2
Application number	US-57592806-A
Country	US
Kind code	B2
Filing date	Jul 14, 2006
Priority date	Jul 15, 2005
Publication date	Jan 24, 2017
Grant date	Jan 24, 2017

Abstract

A rare-earth sintered magnet includes 12.0 at % to 15.0 at % of rare-earth element(s), which is at least one element selected from the group consisting of Nd, Pr, Gd, Tb, Dy and Ho and at least 50% of which is Nd and/or Pr; 5.5 at % to 8.5 at % of boron (B); a predetermined percentage of additive metal A; and iron (Fe) and inevitably contained impurities as the balance. The predetermined percentage of additive metal A includes at least one of 0.005 at % to 0.30 at % of silver (Ag), 0.005 at % to 0.40 at % of nickel (Ni), and 0.005 at % to 0.20 at % of gold (Au).

First claim

The invention claimed is:

1. A magnet comprising:
12.0 at % to 15.0 at % of rare-earth element(s), which is at least one element selected from the group consisting of Nd, Pr, Gd, Tb, Dy and Ho and at least 50% of which is Nd;
5.5 at % to 8.5 at % of boron (B);
a predetermined percentage of additive metal A; and
iron (Fe) and inevitably contained impurities as the balance; wherein
the predetermined percentage of additive metal A includes one of 0.005 at % to 0.10 at % of silver (Ag) and 0.005 at % to 0.10 at % of gold (Au); and
the magnet is a rare-earth sintered magnet; wherein
the inevitably contained impurities include Al, of which the content is 0.4 at % or less.

2. The magnet of claim 1 , comprising 0.005 at % to 0.40 at % of Ni.

3. The magnet of claim 1 , further comprising 0.05 at % to 1.0 at % of element M, which is at least one element selected from the group consisting of Ti, V, Cr, Zr, Nb, Mo, Hf, Ta and W.

Assignees

• Morimoto Hideyuki
• Odaka Tomoori
• Hitachi Metals Ltd

Inventors

• Morimoto Hideyuki
• Odaka Tomoori

Classifications

• B22F3/10

  Sintering only · CPC title

• C22C38/002

  containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60 · CPC title

• C22C38/08

  containing nickel {(C22C38/105 takes precedence)} · CPC title

• H01F1/0577

  sintered · CPC title

• B22F2998/10

  Processes characterised by the sequence of their steps · CPC title