Permanent magnetic materials of the Fe-B-R tpe, containing Ce and Nd and/or Pr, and process for manufacture
AssigneesGeneral Electric Company, Batou Iron and Steel (Group) Co. LTD
InventorsChen Pei Xin, Wang Biao, Ni De Zhen, Mark Gilbert Benz, Juliana C. Shei
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Abstract
A Fe—B—R type permanent magnetic, consisting of: 13-19 atomic % R, where R consists essentially of a mixture of rare earth elements Nd and/or Pr, and Ce, where Ce is between 0.2 and 5.0 wt. % of R; 4-20 atomic % B, and the balance comprising Fe. In a preferred aspect, R comprises 15-16 atomic % B; of which Ce is approximately 0.5% and the remaining rare earths Pr and Nd are in a ratio of 3:1. A process of producing a Fe—B—R permanent magnet as described above, and a Fe—B—R magnetic material made by such process.
Claims20
A magnetic material having a composition of Fe—B—R the material consisting essentially of:
- (i) 13-19 atomic % R, where R consists essentially of a mixture of rare earth elements Nd, Pr, and Ce, wherein Ce is between approximately 0.2 wt. %. and no more than 5.0 wt. % of R, Pr is between about 70-76 wt. % and Nd is 29.8-23.8 wt. %;
- (ii) 4-20 atomic % B;
- and
- (iii) the balance comprising Fe with impurities.
A process for preparing a permanent magnetic material having a composition of Fe—B—R the process comprising the steps of:
- (a) preparing a metallic powder having a mean particle size of 0.3-80 microns, the metallic powder formed from a composition consisting of 15-16 atomic % R, wherein R consists essentially of the light rare earths Nd, Pr, and Ce, wherein Ce is between 0.2-5.0 wt. % of the R, the balance of R consisting essentially of Nd and Pr where Pr is between about 70-76 wt. %, Nd is between 28.9-23.8 wt. %;
- 4-8 atomic % B;
- and at least 52 atomic % Fe;
- (b) compacting the powder at a pressure of at least 1.5 ton/cm2;
- and
- (c) sintering the resulted body at a temperature of 900-1200° C. in a non-oxidizing or reducing atmosphere.
A permanent magnetic material having a composition of Fe—B—R when made in accordance with the following process, namely:
- (a) preparing a metallic powder having a mean particle size of 0.3-80 microns, the metallic powder formed from a composition consisting of 15-16 atomic % R, wherein R consists essentially of the light rare earths Nd, Pr, and Ce, wherein Ce is between 0.2-5.0 wt. % of R, the balance of R consisting essentially of (by wt. %) Nd and Pr;
- 4-48 atomic % B, and at least 52 atomic % Fe;
- (b) compacting the powder at a pressure of at least 1.5 ton/cm2;
- and
- (c) sintering the resulted body at a temperature of 900-1200° C. in a non-oxidizing or reducing atmosphere.
Dependencies are inferred from the claim text.