A method of manufacturing a rare earth permanent magnet material

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A permanent magnet material is prepared by covering an anisotropic sintered magnet body of formula : Rx(Fe1-yCoy)100-x-z-aBzMa wherein Ris a rare earth element, M is Al, Cu or the like, with a powder comprising an oxide of R, a fluoride of Ror an oxyfluoride of Rwherein R, R, and Rare rare earth elements, and having an average particle size up to 100 mum, heat treating the powder-covered magnet body in a hydrogen gas-containing atmosphere for inducing disproportionation reaction on R2Fe14B compound, and continuing heat treatment at a reduced hydrogen gas partial pressure for inducing recombination reaction to said compound, thereby finely dividing said compound phase to a crystal grain size up to 1 mum, and for effecting absorption treatment, thereby causing R, Ror Rto be absorbed in the magnet body.