PRODUCTION METHOD FOR MAGNETIC-ANISOTROPY RARE-EARTH SINTERED MAGNET AND PRODUCTION DEVICE THEREFOR

摘要

Lower oxidation of powder and smaller powder particle size are effective for improving the performance of a rare-earth magnet. A method of producing a magnetic-anisotropy rare-earth sintered magnet capable of safely using very active powder low in oxidation level and small in powder particle size, and a method that can efficiently produce products in various shapes. Fine powder as the raw material of a magnetic-anisotropy rare-earth sintered magnet is filled in a mold until a specified density is reached in a weighing/filling unit (41) and a density-increasing unit (42), the fine powder is oriented by a pulse magnetic field in a magnetic field orientation unit (43), and then the fine powder is sintered in a sintering furnace (44) without being pressed. Since this method can simplify the operation of a mass-production device and reduce the enclosure, powder oxidizing and a danger involving combustion that are problems with a method using a conventional large-scale press device can be eliminated. Products in the most-important shapes of rare-earth magnets such as flat-plate and arcuate-plate magnets can be efficiently produced by using a multi-product mold.