| 摘要 |
<P>PROBLEM TO BE SOLVED: To strike a balance between the suppression of growth of crystal grains in a sintered rare-earth magnet and the increase of the density of the magnet by shortening the sintering time. <P>SOLUTION: In manufacturing the sintered rare-earth magnet by sintering a molding formed by molding fine raw alloy powder containing a rare-earth element, a transition metal element, and boron; the sintering is performed by high-frequency induction heating after a binder removing process is performed by resistance heating. Since the resistance heating is adopted to the binder removing process, the binder removing process can be performed efficiently. In addition, since the high-frequency induction heating is adopted to the sintering, the temperature of the molding can be controlled easily and, accordingly, a sintering pattern can be controlled arbitrarily. Consequently, the promotion of the density increase of the magnet, the suppression of the growth of crystal grains, and the suppression of different phases can be realized simultaneously. At the same time, the reduction of carbon and oxygen is also realized. In addition, the amount of oxygen contained in the fine raw alloy powder is adjusted to ≤2,500 ppm during performing the sintering by the high-frequency induction heating. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
