Title:
HIGH-PERFORMANCE SINTERED NDFEB MAGNET
Document Type and Number:
WIPO Patent Application WO/2017/096676
Kind Code:
A1
Abstract:
A high-performance sintered NdFeB magnet. The high-performance sintered NdFeB magnet is obtained by preparing a sintered NdFeB magnet substrate, forming a heavy rare-earth element-containing coating layer on the surface of the sintered NdFeB magnet substrate, and permeating the sintered NdFeB magnet substrate with the heavy rare-earth element in the heavy rare-earth element-containing coating layer using the heat treatment technology, wherein the lattice constant of a surface position of the high-performance sintered NdFeB magnet in a principal phase z-axis direction is denoted as c1, the lattice constant of an internal center position of the high-performance sintered NdFeB magnet in the principal phase z-axis direction is denoted as c 0, and c1 and c 0 satisfy the following relationship: 0.01% < (c 0 - c1) / c 0 < 1.5%, where the symbol / is a division operation symbol. The present invention is advantageous in that the coercive force of a magnet is increased under the condition that the residual magnetism is not significantly reduced, such that the high coercive force and high residual magnetism are provided at the same time. Also, the heavy rare-earth elements only exist in a grain boundary phase and principal phase epitaxial region of the magnet surface layer, thereby significantly reducing the usage amount of the heavy rare-earth elements in the preparation process to reduce the cost of the magnet.
Inventors:
LV XIANGKE (CN)
LIANG FENGJI (CN)
ZHANG MIN (CN)
DING YONG (CN)
HU YIQUN (CN)
LIANG FENGJI (CN)
ZHANG MIN (CN)
DING YONG (CN)
HU YIQUN (CN)
Application Number:
PCT/CN2016/000376
Publication Date:
June 15, 2017
Filing Date:
July 12, 2016
Export Citation:
Assignee:
NINGBO YUNSHENG CO LTD (CN)
NINGBO YUNSHENG MAGNET DEVICES TECH CO LTD (CN)
BAOTOU YUNSHENG STRONG MAGNETIC MAT CO LTD (CN)
NINGBO YUNSHENG MAGNET DEVICES TECH CO LTD (CN)
BAOTOU YUNSHENG STRONG MAGNETIC MAT CO LTD (CN)
International Classes:
H01F1/057
Foreign References:
| CN105374486A | 2016-03-02 | |||
| CN104134528A | 2014-11-05 | |||
| CN104599829A | 2015-05-06 | |||
| JP2013197558A | 2013-09-30 |
Attorney, Agent or Firm:
NINGBO AOSHENG PATENT AGENT OFFICE (GENERAL PARTNERSHIP) (CN)
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