New strategy for efficient manufacturing of bulk anisotropic nanocrystalline Nd-Fe-B permanent magnets  

作　　者：Qian Li Lingqi Liu Yuqing Li Ming Yue Yuan Teng Weiqiang Liu Dongtao Zhang 

机构地区：[1]School of Materials Science and Engineering,Key Laboratory of Advanced Functional Materials,Ministry of Education of China,Beijing University of Technology,Beijing 100124,China

出　　处：《Journal of Materials Science & Technology》2024年第34期119-129,共11页材料科学技术(英文版)

基　　金：supported by the National Key R&D Program of China(2021YFB3500300);the Natural Science Foundation of China(No.51931007);the Program of Top Disciplines Construction in Beijing under Grant PXM(No.2019_014204_500031).

摘　　要：The application of bulk nanocrystalline Nd-Fe-B permanent magnets manufactured by hot deformation methods was severely limited by production efficiency.Therefore,this work proposed an efficient prepa-ration method combining hot rolling and deformation.Using the melt-spun Nd-Fe-B magnetic powders as original materials,dense,large-sized,and well-uniform precursors for deformation can be obtained through cold pressing and hot rolling.The large-sized hot-rolled magnet can be cut into small pieces and subjected to hot deformation.The deformed magnet exhibits obvious crystallographic anisotropy,and the optimal maximum energy product can reach 35.7 MGOe.Furthermore,the mechanism of defor-mation and texture formation has been systematically studied,according to the microstructure and tex-ture characterization of different height reduction magnets.The results indicated that there was a typical heterogeneous structure in the hot-rolled and hot-deformed Nd-Fe-B magnets.Dissolution precipitation,grain growth,and regular grain arrangement were the main reasons for deformation and texture forma-tion during the deformation process.Our strategy of replacing traditional hot-pressing with large-sized hot-rolling can produce massively deformed precursors at once,greatly improving production efficiency,which is crucial for promoting the application of bulk nanocrystalline anisotropic Nd-Fe-B permanent magnets.

关 键 词：Anisotropic Nd-Fe-B magnet Hot rolling Hot deformation Deformation behavior Magnetic properties 

分 类 号：TG1[金属学及工艺—金属学]