稀土金属类永久磁铁材料之制造方法

A rare earth permanent magnet material is prepared by covering a sintered magnet body of R 1 -Fe-B composition wherein R 1 is a rare earth element, with a powder comprising at least 30% by weight of an alloy of R 2 a T b M c A d H e wherein R 2 is a rare earth element, T is Fe and/or Co, and M is Al, Cu or the like, and having an average particle size up to 100 µm, and heat treating the powder-covered magnet body at a suitable temperature, for causing R 2 , T, M and A in the powder to be absorbed in the magnet body.