| 摘要 |
PURPOSE:To obtain a permanent magnet of high performance by isothermally treating an alloy lump containing a rare-earth element such as Sm and Co, Fe, Cu, Hf, etc. at a specific temperature. CONSTITUTION:An alloy lump having the constitution of R(Co1-x-y-zFexCuyMz)A containing an element R, for which Sm or Ce is used mainly, and M, such as Hf, Zr, Ti, Nb, Cr, Mn, Si, etc. and compositions of 0.01<=x<=0.4, 0.02<=y<=0.25, 0.01<=z<=0.15 and 0.5<=A<=0.3 is held for 1 or forty-eight hr at 950-1,200 deg.C, thus removing the segregation of compositions on dissolution, then promoting homogenization. The alloy lump is quenched by water, etc., pulverized and molded in a magnetic field, sintered at 1,160-1,250 deg.C, and quenched. According to said method, an excellent R2CO17 group permanent magnet having coercive force of 10<3>Oe or more and an energy value of 25MGOe or more and superior square molding capability is obtained. |
