| 摘要 |
PURPOSE:To enable production of magnetic powder having an uniform and fine particle diameter and excellent magnetic characteristics, by adding a flux to coprecipitates in the presence of an alkaline substance to evaporate moisture and firing the resultant substance in producing a ferrite, such as Ba, by a coprecipitating method. CONSTITUTION:An aqueous solution containing Fe ions and one or more metallic ions of Ba, Sr, Ca and Pb at a molar ratio so as to provide 8-16mol. Fe ions and 0.8-3mol. one or more metallic ions is mixed with an aqueous solution of an alkali so as to afford pH >=5. The resultant coprecipitates, which are then heated in the presence of an alkaline substance in an amount of >=0.2mmol. based on 1mol. Fe atom therein and a flux at >=700 deg.C to afford <=70wt.% moisture content. The resultant substance is subsequently fired at 600-1,200 deg.C. The aimed magnetic powder having an equally uniform average particle diameter as small as <=0.15mu and improved magnetic characteristics without aggregating or sintering of particles is obtained by this method.
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