Study on quantitative pulse magnetization of NdFeB

Demagnetization may occur in permanent magnet(PM) motors, remagnetization is needed to recover its magnetic power. In this paper, pulse magnetizing process of sintered NdFeB magnet has been studied. Combining with calculated electromagnetic field distribution by Maxwell 3D FEM software, critical magnetic field to saturate the sintered NdFeB magnet is determined through experiment. Preliminary result shows that pulse magnetic field needed to saturate NdFeB magnet has something to do with its historic magnetization process. Furthermore, once the saturated NdFeB magnet is demagnetized, it will be much harder to resaturate the NdFeB than initial saturation.