Title:
HOT PRESS MOLDING-BASED METHOD FOR PREPARING RARE-EARTH PERMANENT MAGNET
Document Type and Number:
WIPO Patent Application WO/2020/114398
Kind Code:
A1
Abstract:
The present invention relates to a method for preparing a neodymium-iron-boron rare-earth permanent magnetic material, in particular to a hot press molding-based method for preparing a rare-earth permanent magnet. The problem that the residual magnetism and coercive force of a rare-earth permanent magnet prepared in the prior art cannot be both high is solved. An RTM alloy infiltrates same during an HD treatment. RTM sticks to the surface of coarse powder and infiltrates into the interior of the coarse powder along a grain boundary. The temperature of hot press sintering is relatively low, and grains barely grow. In the absence of Dy and Tb, a higher coercive force is obtained. If an alloy containing Dy and Tb is used for infiltration, these atoms diffuse into the surface layer of a main phase during preheating and heat treatment, achieving grain boundary hardening. Under the premise of a very small reduction in the residual magnetism, the coercive force is greatly improved.
Inventors:
DONG YUAN (CN)
Application Number:
PCT/CN2019/122766
Publication Date:
June 11, 2020
Filing Date:
December 03, 2019
Export Citation:
Assignee:
DONG YUAN (CN)
TAIYUAN KAIYUAN INTELLIGENT EQUIPMENT CO LTD (CN)
TAIYUAN KAIYUAN INTELLIGENT EQUIPMENT CO LTD (CN)
International Classes:
H01F1/057; H01F41/02
Foreign References:
| CN108922708A | 2018-11-30 | |||
| CN105006326A | 2015-10-28 | |||
| CN108922766A | 2018-11-30 | |||
| CN102368439A | 2012-03-07 | |||
| CN108922765A | 2018-11-30 | |||
| CN101552060A | 2009-10-07 | |||
| JP2015154051A | 2015-08-24 |
Attorney, Agent or Firm:
BEIJING XURUN LAW FIRM (CN)
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