| 摘要 |
PURPOSE:To improve the coercive force and the rectangularity by adding powder of a specific rare earth oxide to alloy powder of an R-T-M rare earth cobalt intermetallic compound, shaping said powder by pressurization in a magnetic field, and sintering at a specific temperature. CONSTITUTION:Zero-point-zero-one to one per cent by weight of powder of a rare earth oxide such as Sm2O3 is added to alloy powder of a rare earth cobalt intermetallic compound including 22-28wt.% of R (one or more rare earth elements), 2-10wt.% of Cu, 6-35wt.% of T (one or more of Fe, Ni, Mn, and Cr), and 0.5-6wt.% of M (one or more of Zr, Ti, Hf, Nb, V, and Ta) and the principal element of the rest of which is Co. This powder is shaped in a magnetic field and sintered at 1,100-1,250 deg.C. A recommended sintering temperature to obtain high Br is 1,170 deg.C or higher. Said sintered body is processed by solution treatment at a lower temperature than the sintering temperature and quenched. Decrease of the coercive force can be prevented in spite of sintering at a high temperature, the residual magnetic flux density can be heightened, and a magnetic characteristic of high rectangularity can be obtained by thus adding 1wt.% or lower percentage of powder of a rare earth oxide. |
