| 摘要 |
PURPOSE:To enable formation of a long and thin ringlike magnet whose length is enlarged by making specified relation between the velocity of a core pin and the velocity of a die with pressing velocity of a pressing punch and by forming the core pin and the die while moving them is the same direction as that of the pressing punch. CONSTITUTION:Magnet raw powder 7 or a preliminary molding 7 formed by pressing the magnet raw powder is charged inside a green molding space 3 formed of a core pin 2, a die 4 and a pressed punch 6. Then, the pressing punch 5 is pressed at a pressing velocity VP at a specified temperature in vacuum or in inert gas atmosphere to compress the magnet raw powder or the preliminary molding 7. During pressure application by the pressing punch 5 at the pressing velocity VP, the core pin 2 is moved in the same direction as that of the pressurizing punch 5 at a velocity VC and the die 4 is moved in the same direction as that of the pressing punch 5 at a velocity VD. In the process, the velocity VC of the core pin 2 is made (0.5 to 1.0).VP and the velocity VD of the die 4 is made (0.5 to 1.0).VP to compress the magnet raw powder or the preliminary molding 7 of magnet raw powder. Thereby, a thin and long ring-like magnet molding 8 is acquired.
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