Title:
METHOD SUITABLE FOR GRAIN BOUNDARY DIFFUSION OF BULK RARE EARTH PERMANENT MAGNET MATERIAL
Document Type and Number:
WIPO Patent Application WO/2021/136366
Kind Code:
A1
Abstract:
Disclosed is a method suitable for the grain boundary diffusion of a bulk rare earth permanent magnet material. In the present invention, a bulk rare earth magnet is subjected to a grain boundary diffusion treatment by means of a spark plasma sintering technique to improve the comprehensive magnetic performance of the magnet. The method comprises the following steps: (1) preparing an initial magnet by means of a sintering, hot pressing or hot deformation process; (2) loading a grain boundary diffusion alloy source on the surface of the magnet; and (3) placing the loaded initial magnet into a spark plasma device, heating and warming same using spark plasma, and subjecting same to grain boundary diffusion to obtain a final magnet. By controlling the parameters, such as the current and pressure, during spark plasma sintering, the diffusion coefficient and diffusion depth of the element are significantly improved. In the bulk rare earth permanent magnet material, which has been subjected to grain boundary diffusion, prepared by the present invention, the replacement amount of the high-abundance rare earth elements, La, Ce and Y, can reach 80 wt%, the magnetic performance is significantly increased, and is not limited by the thickness of the magnet, and the thickness of the magnet can reach 60 mm, which satisfies the industrial production and market requirements.
Inventors:
JIN JIAYING (CN)
YAN MI (CN)
TAO YONGMING (CN)
LI MEIXUN (CN)
WEI ZHONGHUA (CN)
ZHAO DONGLIANG (CN)
YAN MI (CN)
TAO YONGMING (CN)
LI MEIXUN (CN)
WEI ZHONGHUA (CN)
ZHAO DONGLIANG (CN)
Application Number:
PCT/CN2020/141348
Publication Date:
July 08, 2021
Filing Date:
December 30, 2020
Export Citation:
Assignee:
UNIV ZHEJIANG (CN)
ZHEJIANG INNUOVO MAGNETICS CO LTD (CN)
ZHEJIANG INNUOVO MAGNETICS CO LTD (CN)
International Classes:
H01F41/02; H01F1/055
Foreign References:
| CN111063536A | 2020-04-24 | |||
| CN111091944A | 2020-05-01 | |||
| CN110534331A | 2019-12-03 | |||
| CN106910613A | 2017-06-30 | |||
| JP2017188515A | 2017-10-12 |
Attorney, Agent or Firm:
HANGZHOU QIUSHI PATENT OFFICE CO., LTD. (CN)
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