RARE EARTH PERMANENT MAGNET AND METHOD THEREOF

摘要

The present invention relates to a rare earth permanent magnet and a method for fabricating the rare earth permanent magnet for preventing residual magnetic flux density of a sintered magnet from being reduced and reinforcing coercive force of the sintered magnet by thermally treating the sintered magnet, which is fabricated by mixing and applying metal alloy powder and a rare earth compound, for internal and columnar grain boundary diffusion. More particularly, the method for fabricating the rare earth permanent magnet according to the present invention includes: a step of fabricating an NdFeB sintered magnet; a step of attaching or adhering a grain boundary diffusant in the form of mixed powder composed of the alloy powder including Re^1_aM_b or M and a Re^2 oxide or a Re^2 fluoride to the surface of the NdFeB sintered magnet; and a step of thermally treating the NdFeB sintered magnet with the grain boundary diffusant attached or adhered to the surface of the NdFeB sintered magnet so that at least one among the Re^1, the R2^2 and the M is diffused along the ground boundaries inside the sintered magnet or the columnar grain boundaries of the sintered magnet.