Cr添加对热变形Nd-Fe-B磁体磁性能的影响

doi:10.19976/j.cnki.43-1448/TF.2025034

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Abstract To optimize the structure of the coarse-grained regions in hot-deformed Nd-Fe-B magnets and enhance their structural uniformity. In this paper, Nd-Fe-B magnets with different Cr contents were prepared using fast-quenched magnetic powder and Cr powder as raw materials through hot pressing and hot deformation processes. The effects of Cr content on the microstructure and magnetic properties of the magnets were studied by scanning electron microscope, energy spectrometer, X-ray diffractometer, and the mechanism of its magnetic property changes was revealed. The results indicate that an appropriate addition of Cr can significantly enhance the remanence and maximum magnetic energy product of Nd-Fe-B magnets. When w(Cr) is 0.5%, the remanence and magnetic energy product can reach 1.39 T and 353 kJ/m³, respectively. Cr exists as single particles, and the rare-earth-rich phase enriches around the Cr particles, forming a coating layer, which effectively reduces the inhomogeneous distribution of rare-earth-rich phases, optimizes the overall width and distribution of the coarse-grained regions. Thus, the texture of the magnet is optimized, leading to the improvement of comprehensive magnetic properties.

Key words： magnet material Cr addition hot deformation magnetic property remanence enhancement

Received: 27 March 2025 Published: 13 October 2025

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	Articles by authors
	HOU Pengjun
	WANG Yan
	LIU Yong
	LUO Yang
	WANG Zilong

Cite this article:

HOU Pengjun,WANG Yan,LIU Yong, et al. Effect of Cr addition on magnetic properties of hot-deformed Nd-Fe-B magnets[J]. Materials Science and Engineering of Powder Metallurgy, 2025, 30(4): 378-386.

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http://pmbjb.csu.edu.cn/EN/10.19976/j.cnki.43-1448/TF.2025034 OR http://pmbjb.csu.edu.cn/EN/Y2025/V30/I4/378

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