| 摘要 |
PURPOSE:To obtain a permanent magnet having excellent reproducibility and coersive force characteristic through elimination of a problem of dispersed coersice force by sintering an alloy as the raw material of a permanent magnet and then successively conduct the first stage and second stage ageing processes within a predetermined temperature range. CONSTITUTION:As the composition of starting materials, R of 10-40 wt% selected from rare earth elements, boron of 0.1-8 wt%, cobalt of 5-20 wt%, gallium of 0.2-12 wt%, oxygen of 0.005-0.3 wt% and Fe as the remainder are selected and such alloy materials and sintered. Next, the sintered materials are subjected to the first stage ageing process under the temperature of 500-1200 deg.C and is then cooled. It is then subjected to the second stage ageing process under the temperature of 500-750 deg.C. Thereby a problem of dispersed coersive force of a permanent magnet can be eliminated, such coersive force can be sustained with good reproducibility and the coersive force characteristic may be improved. |
