Title:
HIGH-STRENGTH R-T-B RARE EARTH PERMANENT MAGNET AND PREPARATION METHOD THEREFOR
Document Type and Number:
WIPO Patent Application WO/2022/170862
Kind Code:
A1
Abstract:
Disclosed are a high-strength R-T-B rare earth permanent magnet and a preparation method therefor. The magnet comprises 0.3-1.5 wt.% of Zr; and the method comprises preparing an SC sheet by means of a melt-spinning method, then subjecting same to a high-temperature heat treatment, such that the Zr element in the SC sheet is precipitated in an R-rich phase in the form of a fibrous Zr compound, uniformly mixing the fibrous Zr compound with a magnetic powder by means of combining with hydrogen crushing, preparing a powder by means of jet milling and powder mixing, and during the sintering process, gradually growing the fibrous Zr compound in the shaped compact into a rod, which is present in the R-rich phase at the grain boundary of the sintered body. The morphology, size and distribution of the Zr compound can be effectively controlled by adjusting the technological parameters, such as the Zr content, sintering temperature and sintering time, of the magnet; and the mechanical properties of the magnet can be improved by means of strengthening the R-rich phase at the grain boundary, without the magnetic property of the magnet being reduced.
Inventors:
CHEN BIAO (CN)
FU SONG (CN)
HU XIAOMIN (CN)
ZHANG ZAONENG (CN)
WANG LIXU (CN)
MAN CHAO (CN)
FU SONG (CN)
HU XIAOMIN (CN)
ZHANG ZAONENG (CN)
WANG LIXU (CN)
MAN CHAO (CN)
Application Number:
PCT/CN2021/140334
Publication Date:
August 18, 2022
Filing Date:
December 22, 2021
Export Citation:
Assignee:
ZHEJIANG INNUOVO MAGNETICS CO LTD (CN)
International Classes:
H01F1/057; H01F41/02
Foreign References:
| CN110299234A | 2019-10-01 | |||
| CN113450984A | 2021-09-28 | |||
| CN106024245A | 2016-10-12 | |||
| CN111613407A | 2020-09-01 | |||
| JP2004111481A | 2004-04-08 |
Attorney, Agent or Firm:
HANGZHOU SIKERUI PATENT OFFICE CO., LTD (CN)
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