Detection of Irreversible Flux Loss of Sintered Nd-Fe-B Magnets
CAO Yu-jie1,2,WU Yu-cheng1,LIU You-hao2,XU Guang-qing1,ZHANG Peng-jie3,LIU Jia-qin4,CHEN Jing-wu2,YI Xiao-fei1,2
1. School of Materials Science and Engineering, Hefei University of Technology, Hefei, Anhui 230009, China
2. State Key Laboratory of Rare Earth Permanent Magnet Materials (Earth-Panda Advance Magnetic Material Co. Ltd), Hefei, Anhui 231500, China
3. BGRIMM Magnetic Materials and Technology (Fuyang) Co. Ltd, Fuyang, Anhui 236000, China
4. Institute of Industry and Equipment Technology, Hefei University of Technology, Hefei, Anhui 230009, China
Abstract：The irreversible flux loss is an important performance index of sintered Nd-Fe-B magnets for permanent magnet motor. The accuracy of its measurement results directly affects the design of motor and the selection of magnetic performance. The irreversible flux loss of magnets under different test conditions is studied. The results show that the irreversible flux loss is mainly affected by tray properties (material / specification), magnet spacing and baking temperature. In order to obtain accurate measurement results of irreversible flux loss, these factors should be effectively controlled in the measurement process.
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2021, Vol. 42 
