| 摘要 |
PURPOSE:To prepare a magnet-plumbite ferrite powder having improved magnetic characteristics, by mixing a mixture solution of Ba or Sr chloride or nitrate with a ferrite with an aqueous solution of ammonium carbonate, separating the formed precipitate, and calcining the resultant precipitate. CONSTITUTION:An aqueous solution mixture consisting of Ba<2+> or Sr<2+> chloride or nitrate with ferric chloride or ferric nitrate at (10/1)-(12/1) ratio of Fe to M (M is Ba or Sr) is mixed with an ammoniac alkaline aqueous solution of ammonium carbonate at >=1.3g ion ratio of CO3<2-> to M<2+> and >=4.0g ion ratio of OH<-> to Fe<2+>. The resultant aqueous solution mixture is then stirred to separate the formed precipitate, which is washed to give <=3wt% ammonium salt content in the precipitate in the dried state. The resultant washed precipitate is then calcined at 600-1,300 deg.C to give the aimed magnet-plumbite ferrite powder of stable quality at a low cost. |
