NdFeB rare earth permanent magnets are widely used in permanent magnet motors due to their high remanence, high coercivity and high magnetic energy product. However, their relatively poor thermal stability and low service temperature limit the application of NdFeB magnets. The coercivity can be effectively improved by doping with heavy rare earths to compensate for the flux loss at high temperature. However, the antiferromagnetic coupling between heavy rare earth atoms and Fe atoms will also reduce the remanent magnetization and magnetic energy product of NdFeB magnets. The influence of heavy rare earth doping on the remanence and magnetic energy product of NdFeB magnets can be reduced by process selection and process optimization control while increasing the coercivity as much as possible. The improvement of the performance of heavy rare earth doping can effectively avoid the local demagnetization of magnets, thus expanding its application prospects and potential in permanent magnet motors.

heavy rare earth doped NdFeB;coercivity;permanent magnetic machine;comprehensive performance