稀土金属类永久磁铁材料之制造方法

A method for preparing a rare earth permanent magnet material comprises the steps of disposing a powder on a surface of a sintered magnet body of R 1 a T b A c M d composition wherein R 1 is a rare earth element inclusive of Sc and Y, T is Fe and/or Co, A is boron (B) and/or carbon (C), M is Al, Cu, Zn, In, Si, P, S, Ti, V, Cr, Mn, Ni, Ga, Ge, Zr, Nb, Mo, Pd, Ag, Cd, Sn, Sb, Hf, Ta, or W, said powder comprising an oxide of R 2 , a fluoride of R 3 or an oxyfluoride of R 4 wherein R 2 , R 3 , and R 4 are rare earth elements inclusive of Sc and Y and having an average particle size equal to or less than 100 µm, heat treating the magnet body and the powder at a temperature equal to or below the sintering temperature of the magnet body for absorption treatment for causing R 2 , R 3 , and R 4 in the powder to be absorbed in the magnet body, and repeating the absorption treatment at least two times. According to the invention, a rare earth permanent magnet material can be prepared as an R-Fe-B sintered magnet with high performance and a minimized amount of Tb or Dy used.