Coercivity enhancement of hot-deformed NdFeB permanent magnets with AlCuZn eutectic alloy grain boundary diffusion

• 作者: Ye-Qi Yu Kuo-She Li Hai-Jun Peng Xin-Yuan Bai Ning-Tao Quan Kai-Wen Wu Yang Luo Dun-Bo Yu
• 来源期刊: 稀有金属（英文版）
• 年，卷（期）: 2022,（1）
• 所属期刊栏目: RARE METALS(Monthly)
• 页码范围: 226-231
• 页数: 6页
• 语种: 英文

摘要

It is approved that grain boundary diffusion is an effective method to increase the coercivity of hot-deformed NdFeB magnet.In this paper,a new rare earth-free grain boundary diffusion source of hot-deformed magnet was studied.AlCuZn powders blended with commercial NdFeB powders were hot-compacted to obtain fully dense mag-nets,hot-deformed into anisotropic magnets and finally annealed to gain better homogeneity.Initially,the influ-ences of annealing temperature and time on the magnetic properties of the specimens were studied and the optimal parameters of 600 ℃ and 60 min were achieved.Then,by changing the proportions of AlCuZn grain boundary dif-fusion,the coercivity,remanence and maximum energy product of the hot-deformed NdFeB magnets were exam-ined.The result showed that with 1.0 wt％ AlCuZn grain boundary diffusion and annealing at 600 ℃ for 60 min,the coercivity rose from 828 to 987 kA·m-1 without deterio-rating the remanence.Microstructural analysis confirmed that AlCuZn diffused into the intergranular boundaries and the magnet diffused with AlCuZn possessed finer grains than that of without AlCuZn grain boundary diffusion.