METHOD FOR PRODUCING RAW MATERIAL POWDER FOR RARE EARTH SINTERED MAGNET, METHOD FOR PRODUCING RARE EARTH SINTERED MAGNET, GRANULE AND SINTERED ARTICLE

摘要

A method for producing a raw material powder for a rare earth sintered magnet, characterized in that it has a step of adding an organic liquid to primary alloy particles having a prescribed composition, to prepare a mixture, and a step of preparing, by the use of the mixture, granules formed by attaching primary alloy particles to one another via the organic liquid. In the method, it is preferred that the organic liquid is added in an amount of 1.5 to 15.0 wt % to the primary alloy particles. When the amount is less than 1.5 wt %, it may be difficult to prepare granules with good efficiency, and when the amount is more than 15.0 wt %, an organic moisture may present in an excess amount and it may be required to remove an unnecessary moisture for carrying out compacting in an appropriate magnetic field. The above method allows the improvement of the dimensional accuracy of the resultant compact for a rare earth sintered magnet and the improvement of productivity with no greatly adverse effect on characteristics of the magnet, due to the above granules exhibiting excellent fluidity.