Great influence of demagnetization history on internal interaction and magnetization process of mischmetal-based magnets  

作　　者：Dan Liu Jiefu Xiong Lichen Wang Xinqi Zheng Xin Ming Jiaying Jin Jiazheng Hao He Bai Zhenxing Li Tongyun Zhao Fengxia Hu Jirong Sun Jun Shen Baogen Shen 

机构地区：[1]Department of Physics,Beijing Technology and Business University,Beijing 10048,China [2]Ningbo Institute of Materials Technology&Engineering,Chinese Academy of Sciences,Ningbo 31521,China [3]School of Materials Science and Engineering,University of Science and Technology Beijing,Beijing 100083,China [4]School of Materials Science and Engineering,Zhejiang University,Hangzhou 310027,China [5]Spallation Neutron Source Science Center,Dongguan 523803,China [6]School of Mechanical Engineering,Beijing Institute of Technology Beijing 100081,China [7]Beijing National Laboratory for Condensed Matter Physics,Institute of Physics,Chinese Academy of Sciences,Beijing 100190,China [8]School of Physical Sciences,University of Chinese Academy of Sciences,Beijing 101408,China [9]Ganjiang Innovation Academy,Chinese Academy of Sciences,Ganzhou 341000,China

出　　处：《Science China(Physics,Mechanics & Astronomy)》2025年第2期183-192,共10页中国科学:物理学、力学、天文学(英文版)

基　　金：supported by the National Natural Science Foundation of China(Grant No.52371169);the National Natural Science Foundation of China(Grant Nos.52088101,52001012,12204268,and 92263202);the National Key R&D Program of China(Grant No.2023YFA1610400);the“Leading Goose”R&D Program of Zhejiang Province(Grant No.2022C01110);the Challenge-led projects of China Rare Earth Group(Grant No.ZXKCJBGS-202405-06);the Young Elite Scientists Sponsorship Program by CAST(Grant No.YESS20230329);the Young Elite Scientists Sponsorship Program by BAST(Grant No.BYESS2023302);the National Key R&D Program of China(Grant Nos.2021YFB3501202,2022YFB3505201,and 2019YFA0704900);the Strategic Priority Research Program B of Chinese Academy of Sciences(Grant No.XDB33030200)。

摘　　要：The magnetization process and corresponding magnetization curve are usually used to analyze the coercivity mechanism of NdFe-B based sintered magnet.However,different demagnetization histories will seriously influence the magnetization curve,leading to an inaccurate understanding and analysis of magnetization process.In this work,we investigated the magnetization behavior of multi-main phase(MMP)magnets with thermal demagnetized and alternating current demagnetized states.Recoil curves of initial magnetization process and demagnetization process of thermal demagnetized magnets reflect the movement of domain walls inside the grains and the magnetization interaction between the grains,respectively.It is noted that the former process cannot represent the magnetization reversal of the entire magnet,which is not appropriate to analyze coercivity mechanism alone.While the recoil curves of both two processes of AC demagnetized magnets can illustrate the magnetization reversal of the entire grains and the interaction between grains.Magneto-optical Kerr microscope shows that the grains of thermal demagnetized magnets are in multi-domain states,and the grains of AC demagnetized magnets are almost in singledomain states.Domain walls of thermal demagnetized magnets move easily within the grains,which is more conducive to magnetization saturation in industrial production.In addition,the minorloops of thermal demagnetized magnets can independently represent the transition of grains from multi-domain to single-domain and the demagnetization of single-domain grains,which is equivalent to characterizing the internal interactions by recoil curves.The investigation of magnetization characteristics of MMP sintered magnets starting from different demagnetized states is helpful to further understand the internal interaction and magnetic hardening mechanism.

关 键 词：permanent magnet demagnetization history magnetization reversal misch-metal rare earth 

分 类 号：TM273[一般工业技术—材料科学与工程]