永磁体磁性能的影响
( 四川大学 材料科学与工程学院， 成都 610065)
摘 要: 研究了磁场热处理工艺对Nd10.5Fe76.4Co5Zr2B6.1永磁体组织结构和磁性能的影响，采用XRD、AFM等方法对合金的组织结构、晶化行为进行了研究。结果表明：与传统热处理工艺相比，晶化过程中外加磁场可促进快淬NdFeB粉末的晶化，降低晶化温度，缩短晶化时间；磁场热处理可细化晶粒，增强晶粒间磁交换耦合作用，提高磁性能；在外加磁场为0.28 T，经670 ℃／10 min晶化处理后，可获得最佳磁性能，Br＝0.670 T，Hcj＝687 kA/m，Hcb＝427 kA/m，(BH)m=75kJ/m3。
关键字: 磁场热处理；纳米复相磁体；磁性能
magnetic properties of Nd2Fe14B/α-Fe
nanocrystalline permanent magnets
（ College of Materials Science and Engineering,
Sichuan University, Chengdu 610065, China）
Abstract: The crystallization behavior and microstructure of Nd10.5Fe76.4Co5Zr2B6.1 permanent magnets were studied by X-ray diffraction (XRD) and atomic force microscopy (AFM). Effect of magnetic-field heat treatment on microstructure and magnetic properties was discussed. The results show that, compared with the conventional heat treatment, an externally applied magnetic field during heat treatment of a melt-spun NdFeB powder can promote crystallization from amorphous phase, decrease the crystallization temperature and shorten the crystallization time. Magnetic-field heat treatment can refine grains, enhance the exchange coupled interaction between the grains, and increase the magnetic properties. The optimal magnetic properties of Nd10.5Fe76.4Co5Zr2B6.1 (Br＝0.670 T，Hcj＝687 kA/m，Hcb＝427 kA/m，(BH)m=75 kJ/m3) are obtained while annealed at 670 ℃ for 10 min with an external magnetic field of 0.28 T.
Key words: magnetic-field heat treatment; nanocomposite magnets; magnetic properties
