HDDR各向异性钕铁硼磁粉研究及应用进展

杨俊; 黄东亚; 王岳; 莫漫漫; 林百春; 杨澍

HDDR各向异性钕铁硼磁粉研究及应用进展

中国船舶集团有限公司第七二五研究所, 河南洛阳 471023

详细信息

作者简介:
杨俊,男,1987年生,工程师,研究方向:稀土磁性材料。

中图分类号: TM273
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- 被引次数: 0
出版历程
- 收稿日期: 2022-07-15
- 网络出版日期: 2023-05-06

Research and Application Progress on Production of Anisotropic NdFeB Magnetic Powder by HDDR Process

Luoyang Ship Material Research Institute, Luoyang 471023, China

摘要

摘要: 吸氢-歧化-脱氢-再复合工艺(HDDR)是生产各向异性钕铁硼磁粉的有效方法,其制备的各向异性粘结磁体性能高,重量轻,在提高微特电机功效、减轻重量等方面发挥着重要作用,目前在汽车、无人机等领域已产业化应用。为了提高磁粉性能,科研人员仍不断探究HDDR工艺与各向异性机理,采用晶界扩散法优化磁粉晶界结构,提高磁粉矫顽力与温度稳定性,同时将上述成果应用到废旧烧结钕铁硼回收中,节约稀土资源。HDDR各向异性磁粉性能显著高于各向同性磁粉的,但形变塑性次之,研究者试图将其作为热变形磁体前驱原材料,进一步提升热变形磁体性能。HDDR工艺细化晶粒的效果为提高烧结钕铁硼矫顽力提供了一条新的研究途径,但目前还未获得理想的成果。本研究主要介绍近年来HDDR工艺与机理的发展以及其在稀土磁体回收、热变形磁体、烧结磁体等方面的应用情况。
- 钕铁硼 /
- HDDR工艺 /
- 磁粉 /
- 磁各向异性
Abstract: Hydrogenation-disproportionation-desorption-recombination (HDDR) process is an effective method to produce anisotropic NdFeB magnetic powders. The anisotropic bonded magnets prepared by HDDR process have excellent performance and light weight, which play an important role in improving the efficiency and reducing weight of micro-special motor. It has been industrialized and applied in automotive, drone and other fields. In order to improve the magnetic powder properties, the researchers are keeping investigating the HDDR process and the anisotropy mechanism. They optimize the grain boundary structure of the magnetic powders by using the grain boundary diffusion method to improve the coercivity and temperature stability of the magnetic powder, and apply the above achievements into the recycling of the waste sintered NdFeB to save rare earth resources. The magnetic property of the HDDR anisotropic magnetic powders is better than that of the isotropic magnetic powders, but the deformation plasticity comes after. The researchers attempt to take the HDDR magnetic powders as precursor material to fabricate hot deformation magnets to improve their performances. The effect of grain refinement of the HDDR process provides a new research approach for improving the coercivity of the sintered NdFeB magnets, however, until now, no ideal result has been obtained. In this paper, the development of HDDR process and its mechanism over the years are introduced, as well as its application in hot deformation magnets, sintered magnets and rare earth magnet recycling.
- NdFeB /
- HDDR process /
- magnetic powder /
- magnetic anisotropy

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参考文献(95)

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