摘要 |
The object of the present invention is to improve the productivity of a permanent magnet and to manufacture it at a low cost by effectively coating Dy and Tb on a surface of the magnet of Fe—B-rare earth elements having a predetermined configuration. The permanent magnet of the present invention is manufactured by a coating step for coating Dy on the surface of the magnet of Fe—B-rare earth elements having a predetermined configuration and a diffusing step for diffusing Dy coated on the surface of the magnet into crystal grain boundary phases of the magnet with being heat treated at a predetermined temperature. In this case, the coating step comprises a first step for heating a process chamber used for carrying out the coating step and generating metallic vapor atmosphere within the process chamber by vaporizing vaporizable metallic material previously arranged within the process chamber, and a second step for introducing into the process chamber the magnet held at a temperature lower than that within the process chamber and then selectively depositing the vaporizable metallic material on a surface of the magnet by an effect of temperature difference between the temperature within the process chamber and that of the magnet by the magnet reaches a predetermined temperature. |