| 摘要 |
PURPOSE:To obtain a composite ferrite magnetic powder having excellent orientation, high saturation magnetization as well as minor temperature fluctuation in coercive force and low electric resistance of the powder by forming a specific spinel ferrite layer on the surface of specific ferrite powder. CONSTITUTION:The hexagonal system ferrite powder displaying hexagonal platy shape in the crystalline structure having the whole broad peak excluding those on 110 and 220 surface in X-ray diffraction spectrum usin Kalpha rays of Cu are heat-treated. Next, a spinel ferrite layer represented by a general formula of a (M 'O) Fe2O3 (where M' represents exceeding one kind of metallic elements selected out of Co, Ni, Zn, Cu, Mg, Mn and Fe(II) while O<a<=1) is formed on the surface of the ferrite powder. Through these procedures, the title compound ferrite powder having excellent orientation, high saturation magnetization as well as minor temperature fluctuation in coercive force and low electric resistance of the powder can be obtained. |
