Title:
SINTERED NEODYMIUM-IRON-BORON MAGNET AND ANTI-CORROSION TREATMENT METHOD THEREFOR
Document Type and Number:
WIPO Patent Application WO/2022/134662
Kind Code:
A1
Abstract:
Disclosed are a sintered neodymium-iron-boron magnet and an anti-corrosion treatment method therefor. The method comprises: carrying out heat treatment on the sintered neodymium-iron-boron magnet in an oxidizing atmosphere containing an alcohol and/or an organic acid, wherein the ratio of the oxygen partial pressure to the vapor partial pressure in the oxidizing atmosphere containing an alcohol and/or an organic acid is 1-300 : 1, the temperature of the heat treatment is less than or equal to 300ºC, and the time is 10-200 min. By means of the present invention, by adding an alcohol and/or an organic acid to the oxidizing atmosphere and carrying out the heat treatment within the specific temperature range of less than 300ºC, the heating rate of the heat treatment does not need to be controlled; and not only it can be ensured that the magnetic property of the neodymium-iron-boron magnet is not reduced, but also the corrosion resistance performance of the surface of the neodymium-iron-boron magnet can be improved, and additionally, the emergence of cracks in the surface of the neodymium-iron-boron magnet is reduced. Moreover, the method of the present invention is suitable for neodymium-iron-boron magnets with any oxygen content and specification, and the neodymium-iron-boron magnets can all be subjected to an oxidation heat treatment within the specific temperature range of less than 300ºC to form a corrosion-resistant film layer.
Inventors:
BAI XIAOGANG (CN)
YU HAIHUA (CN)
PAN GUANGHUI (CN)
HAN XUE (CN)
YU HAIHUA (CN)
PAN GUANGHUI (CN)
HAN XUE (CN)
Application Number:
PCT/CN2021/117726
Publication Date:
June 30, 2022
Filing Date:
September 10, 2021
Export Citation:
Assignee:
TIANJIN SANHUAN LUCKY NEW MAT CO LTD (CN)
BEIJING ZHONG KE SAN HUAN (CN)
BEIJING ZHONG KE SAN HUAN (CN)
International Classes:
H01F1/057; H01F41/02
Foreign References:
| CN112259359A | 2021-01-22 | |||
| CN101809690A | 2010-08-18 | |||
| JPH0232511A | 1990-02-02 | |||
| JP2012204581A | 2012-10-22 | |||
| CN104008844A | 2014-08-27 |
Attorney, Agent or Firm:
BEIJING LAWSING IP FIRM (CN)
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