METHOD FOR PRODUCING RARE EARTH PERMANENT MAGNET MATERIAL

摘要

A method for preparing a rare earth permanent magnet material comprising the steps of:
disposing a powder comprising one or more members selected from an oxide of R 2 , a fluoride of R 3 , and an oxyfluoride of R 4 wherein R 2 , R 3 and R 4 each are 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, 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. The invention offers a high performance, compact or thin permanent magnet having a high remanence and coercivity at a high productivity.