PURPOSE: To obtain the economical permanent magnet of excellent magnetic characteristics by boiling, washing and removing excessive MO remaining after wet type crusing.
CONSTITUTION: When powdered grains consisting of magnet plumbite type crystals represented by a chemical formula MO.nFe2O3 (where M is Ba or Sr and n 4.5W6.0) are calcined, wet-type crushed, molded in a magnetic field and sintered and the oxide permanent magnet is manufactured, boiling and washing processes are added after wet-type crushing. The temperature of water is approximately 50°C or lower on wet type pulverizing, and Sr(OH)2, etc. hardly dissolve, but their solubility increases largely through boiling. Accordingly, the magnet, magnetic characteristics thereof are improved, can be obtained easily by removing MO or M(OH)2 (M is Ba or Sr) remaining after crushing by repeating boiling and wash.
YOKOYAMA TOSHIHIKO
IDEI KAZUHIKO
HONDA KEIICHI
