摘要
The magnetic field stability of the PrFeB magnets is one of the key points which affect its application in such devices as cryogenic permanent magnet undulators. In this study, the magnetic properties and micro structure of PrFeB magnets, which were developed by the grain boundary diffusion, were examined. The demagnetizing field distribution of the cryogenic permanent magnet undulator made using the PrFeB magnets was simulated by Radia, and the change mechanism of the irreversible demagnetization following treatments at high temperatures was experimentally studied, The results show that the intrinsic coercivity of the PrFeB magnets can be increased by diffusion of Tb. Meanwhile, the remanence of the magnets displays almost no loss, and the increasing range is closely related to the orientation thickness of the PrFeB magnet, Therefore, the PrFeB magnets developed using grain boundary diffusion are found to have extremely high comprehensive magnetic properties, The irreversible demagnetization of the PrFeB magnets developed by grain boundary diffusion for the CPMU is determined to be significantly improved following high-temperature treatments.
The magnetic field stability of the PrFeB magnets is one of the key points which affect its application in such devices as cryogenic permanent magnet undulators. In this study, the magnetic properties and micro structure of PrFeB magnets, which were developed by the grain boundary diffusion, were examined. The demagnetizing field distribution of the cryogenic permanent magnet undulator made using the PrFeB magnets was simulated by Radia, and the change mechanism of the irreversible demagnetization following treatments at high temperatures was experimentally studied, The results show that the intrinsic coercivity of the PrFeB magnets can be increased by diffusion of Tb. Meanwhile, the remanence of the magnets displays almost no loss, and the increasing range is closely related to the orientation thickness of the PrFeB magnet, Therefore, the PrFeB magnets developed using grain boundary diffusion are found to have extremely high comprehensive magnetic properties, The irreversible demagnetization of the PrFeB magnets developed by grain boundary diffusion for the CPMU is determined to be significantly improved following high-temperature treatments.
基金
Project supported by the Natural Science Foundation of Shanghai(15ZR1448000)
the State Key Lab of Advanced Metals and Materials(2016-Z03)
