| 摘要 |
PURPOSE:To obtain a permanent magnet alloy having improved magnetic characteristics by compacting alloy powder of a specified particle size consisting of rare earth elements, B and Fe, sintering the green compact at a specified temp., heating, holding and cooling the sintered body under specified conditions and aging it. CONSTITUTION:An alloy consisting of one or more kinds of rare earth elements including Y, B and Fe with inevitable impurities is pulverized to 0.3-80mum average particle size and compacted under about 0.5-10t/cm<2> pressure. The green compact is sintered at 900-1,200 deg.C in an atmosphere of a nonoxidizing or reducing gas. The sintered body is heated to 700-1,000 deg.C in an atmosphere of an inert or reducing gas, held for about 0.5-10hr and cooled to <=350 deg.C at about 0.2-20 deg.C/min cooling rate. Heating holding and cooling are further carried out twice or more in vacuum or in an atmosphere of one or more kinds of gases such as Ar, He, H2 and N2. At this time, the holding temp. is 400-800 deg.C. The sintered body is then aged by carrying out final cooling to <=350 deg.C. |
