Coercivity enhancement of nanocrystalline Ce-based magnets utilizing simplified one-step hot deformation process  

作　　者：Xue-Feng Liao Qing Zhou Wei-Wei Zeng Bang Zhou Hong-Ya Yu Wei-Da Huang Wen-Bing Fan Jia-Sheng Zhang Zhong-Wu Liu 

机构地区：[1]School of Materials Science and Engineering,South China University of Technology,Guangzhou,510640,China [2]Guangdong Provincial Key Laboratory of Rare Earth Development and Application,Institute of Resources Utilization and Rare Earth Development,Guangdong Academy of Sciences,Guangzhou,510640,China

出　　处：《Rare Metals》2025年第1期531-542,共12页稀有金属(英文版)

基　　金：supported by the National Natural Science Foundation of China(Nos.U21A2052,52071143 and 52301237);Guangdong Basic and Applied Basic Research Foundation(Nos.2023A1515010431 and 2022A1515011453);China Postdoctoral Science Foundation funded project(No.2022M720845);GDAS Project of Science and Technology Development(Nos.2022GDASZH-2022010104 and 2023GDASZH-2023010104)。

摘　　要：Nanocrystalline Ce-based rare earth(RE)-Fe-B alloys exhibit relatively good hard magnetic properties and high performance-cost ratio,but their properties deteriorate seriously after hot deformation(HD).Here,we present a simplified one-step HD process for preparing anisotropic Ce-based Ce_(25.88)La_(2.85)Y_(4.56)Fe_(65.73)B_(0.98)(wt%)magnets.The precursor of nanocrystalline powders is first compacted inside a copper tube,and then the powders with the tube are deformed together to achieve magnetic anisotropy.Compared with the conventional two-step HD magnet,i.e.,hot pressing followed by HD,one-step HD significantly increased the coercivity from 1.6 to 3.0 kOe,and the maximum magnetic energy product was improved from 3.7 to 4.8 MGOe.The microstructure characterization indicates that one-step HD can not only produce a more desirable microstructure,characterized by well-aligned platelet-shaped grains with reduced aspect ratio but also greatly inhibit the formation of coarse grain(CG)region.Both of them have been confirmed to be beneficial to enhancing coercivity by micromagnetic simulations.Our results thus demonstrate that the simplified one-step HD process offers a promising approach to developing high-performance anisotropic Ce-based magnets.

关 键 词：Hot deformation(HD) Ce-Fe-B COERCIVITY Coarse grain(CG) Aspect ratio 

分 类 号：TG1[金属学及工艺—金属学]