(北京工业大学 材料科学与工程学院
新型功能材料教育部重点实验室, 北京 100022)
摘 要: 采用放电等离子烧结技术制备高性能新型NdFeB永磁材料, 研究烧结工艺和热处理工艺对磁体组织性能的影响。 采用扫描电子显微镜观察磁体的微观组织， 利用B-H回线仪检测磁体的磁性能。 结果表明： 较高的烧结温度有利于磁体的致密化， 但过高的温度则阻碍液相在主相晶界的浸润， 从而降低磁体的致密度。 在优化工艺条件下制备出具有独特的微观组织且最佳性能为Br＝1.351 T， Hci＝674.4 kA/m， BHm＝360.4 kJ/m3的新型SPS NdFeB磁体。
关键字: 放电等离子烧结; NdFeB永磁材料; 富钕相; 热处理
（ Key Laboratory of Advanced Functional Materials, Ministry of Education, College of Materials Science and Engineering, Beijing University of Technology, Beijing 100022）
Abstract: A new type of NdFeB magnet with high magnetic properties was prepared by spark plasma sintering(SPS) method. The effect of sintering and heat treatment techniques on microstructures and magnetic properties of magnets was systematically studied. The microstructures and magnetic properties of magnet materials were tested by scanning electronic microscope (SEM) and B-H loop-line instrument, respectively. The results show that the densification of magnets is greatly improved with the increase of sintering temperature, while exorbitant sintering temperature will decrease the density of magnets because the Nd-rich phase distributes poorly along the boundaries of the NdFeB grains. Under optimum processing conditions, the SPS NdFeB magnet possesses the best magnetic properties with remanence of 1.351 T, coercive force of 674.4 kA/m and maximum energy product of 360.4 kJ/m3.
Key words: spark plasma sintering; NdFeB permanent magnet; Nd-rich phase; heat treatment
