| 摘要 |
PURPOSE:To suppress the particle size growth of barium ferrite powders and to shorten a washing time by adding magnesium ions to barium ferrite powders synthesized by a wet method and by performing surface treatment on barium ferrite particles. CONSTITUTION:Magnesium ions are added to a barium ferrite product obtained by reacting a water solution containing Fe<3+> and Ba<2+> or its suspension using a wet method in highly concd. alkalis at room temperatures to neutralize a barium ferrite product. After that, washing, filtering and heat treatment are performed. A water solution containing starting materials, Fe<3+> and Ba<2+>, is prepared by dissolving water soluble Fe<3+> salts and water soluble Ba<2+> salts in pure water. The mole ratio (Fe/Ba) of Fe and Ba is preferably 9-12. This enables the particle size growth of barium ferrite particles to be suppressed and a washing time to be shortened. |
