| 摘要 |
PURPOSE:To obtain a magnetic power having uniform composition and is suitable for magnetic perpendicular recording in high density by a method wherein alkali is made to come in contact with an aqueous solution containing ferric salt, cobalt salt and one or more of barium salt, calcium salt abd strontium salt to make to coprecipitate. CONSTITUTION:A mixed liquid containing alkali and alkali carbonate is made to come in contact with an aqueous solution containing ferric salt, cobalt salt and one or more of barium salt, calcium salt and strontium salt to obtain a coprecipitated substance. The coprecipitated substance is washed, dried and is heat-treated (for example, at 950 deg.C) to obtain ferric corpuscles of hexagonal system substituted by Co having average particle diameter of about 0.01-0.3mu. By this way, a magnetic powder having uniform composition, systematic form and is suitable for magnetic perpendicular recording in high density can be obtained. |
