Patent ID: 8211327

Claim:
A method for preparing a rare earth permanent magnet material comprising the steps of: disposing a powder comprising an oxide of R 2 , wherein R 2 is one or more elements selected from among rare earth elements inclusive of Y and Sc on a sintered magnet form of a R 1 —Fe—B composition wherein R 1 is one or more elements selected from among rare earth elements inclusive of Y and Sc, said sintered magnet form having a dimension of at least 0.5 mm in a magnetic anisotropy direction, and heat treating the magnet form and the powder at a temperature equal to or below the sintering temperature of the magnet in vacuum or in an inert gas, wherein said powder comprising an oxide of R 2 having an average particle size of up to 100 μm is disposed in the surface of the magnet form as a slurry thereof dispersed in an aqueous or organic solvent.