| 摘要 |
PURPOSE:To suppress flocculation of ferrite and to obtain magnetic powder having improved dispersibility by adding fine soft magnetic or antiferromagnetic metallic particles to a sintered body pulverized after a heat treatment and treating the same with a dilute acid while impressing a high-frequency magnetic field thereto. CONSTITUTION:The fine soft magnetic or antiferromagnetic metallic particles are added to the sintered body subjected to the pulverization and the treatment thereof is executed under the impression of the high-frequency magnetic field thereto in a stage for extracting the crystal of hexagonal ferrite by treating the sintered body subjected to the pulverization with the dilute acid. The fine soft magnetic or antiferromagnetic metallic powder to be used is exemplified by chromium, nickel, manganese, molybdenum, etc., and the grain size thereof ranges preferably 0.01-0.5mum. The amt. of said powder to be added is 0.01-0.5wt% by the weight of the sintered body subjected to the pulverization after the heat treatment. A magnetorestriction effect is thereby generated in the ferrite, by which the sepn. between the ferrite crystal and glass phase is accelerated and the fine soft magnetic or antiferromagnetic metallic particles are intruded among the ferrite particles to suppress the flocculation of the ferrite particles. The dispersibility is thus improved. |
