简介 |
Rare earth alloy powder having an oxygen content of 50 to 4000 wt. ppm and a nitrogen content of 150 to 1500 wt. ppm is compacted by dry pressing to produce a compact. The compact is impregnated with an oil agent and then sintered. The sintering process includes a first step of retaining the compact at a temperature of 700 DEG C to less than 1000 DEG C for a period of time of 10 to 420 minutes and a second step of permitting proceeding of sintering at a temperature of 1000 DEG C to 1200 DEG C. The average crystal grain size of the rare earth magnet after the sintering is controlled to be 3 mu m to 9 mu m. |