Grain boundary diffusion cerium-rich magnet and preparation method thereof

The invention provides a grain boundary diffusion cerium-rich magnet and a preparation method thereof. The preparation method comprises the steps that a diffusion alloy containing RedX1-d is used as a diffusion source to conduct grain boundary diffusion at the melting point temperature of a base material REFe2 phase, finally tempering treatment is conducted, the cerium-rich magnet is obtained, Re in the diffusion alloy is Nd and/or Pr, X is one or more of Al, Cu, Ga, Sn and Pb, and d is larger than or equal to 0.2 and smaller than or equal to 0.6. The specific diffusion alloy is adopted as a diffusion source in the grain boundary diffusion process, no heavy rare earth needs to be used, the raw material cost is greatly reduced, meanwhile, the grain boundary diffusion process is carried out at the melting point temperature of the base material REFe2 phase, the coercive force is remarkably improved, and the reduction amplitude of residual magnetism is small. 本发明提供了一种晶界扩散富铈磁体及其制备方法。该制备方法包括使用含RedX1-d的扩散合金作为扩散源在基材R