摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing a rare earth permanent magnet, by which a high-performance rare earth magnet having a good residual magnetic flux density and a high coercive force can be efficiently produced.SOLUTION: In a method for producing a rare earth permanent magnet, a sintered magnet body comprising a R-Fe-B based composition (Rrepresents one or two or more elements selected from rare earth elements including Y and Sc) is immersed in an electrodeposition liquid obtained by dispersing powder containing an oxide of R(Rrepresents one or two or more selected from rare earth elements including Y and Sc) in a solvent, an electrodeposition process is used to coat the powder to the surface of the sintered magnet body, and, in the state where the powder is present on the surface of the magnet body, the magnet body and the powder are subjected to heat treatment in a vacuum or inert gas at a temperature equal to or less than the sintering temperature of the magnet. By the method, a coating quantity of powder can be easily controlled, and a powder coating film small in variation of film thickness, precise, and less in unevenness of coating can be formed on the surface of a magnet body with good adhesion. Further, a large area can be efficiently processed for a short time, and a high-performance rare earth magnet having a good residual magnetic flux density and a high coercive force can be extremely efficiently produced. |