PURPOSE: To provide a device for producing rare earth magnet powder in which the temp. of a magnet raw material is uniformized in hydrogen treatment for the magnet raw material and advantageous to the evasion of dispersion in magnetic properties.
CONSTITUTION: Many reaction tubes 10 holding rare earth magnet raw materials 2 are charged to a heating device 4. Furthermore, gaseous hydrogen is fed to each reaction tube 10 by a gaseous hydrogen feeding device 5, furthermore, the magnet raw materials 2 are heated by the heating device 4, and hydrogen occluding stage is executed. In this stage, the temp. is regulated to about 800°C, the time to about 3hr, and the pressure of hydrogen to 1.2 to 1.5atm. After that, a vacuum pump 60 is operated to reduce the pressure in the reaction tubes into a vacuum (e.g. 10-5 to 10-9Torr), and hydrogen occluded in the magnet raw materials 2 is forcedly released; where the temp. is regulated to 775 to 850°C, and the time to about 30min. After that, the magnet raw materials 2 are rapidly cooled.
MITARAI HIROSHIGE
AMAHIRO GIICHI
