| 摘要 |
PROBLEM TO BE SOLVED: To enhance coercive force with little addition of an additive such as Al2O3, or without the additive by containing inorganic particles including at least SiO2, and allowing the total cross-sectional area of inorganic particles, each of which has a cross sectional area within a specified range to occupy a specified area of a sintered magnet cross sectional area. SOLUTION: A sintered magnet has a ferrite main phase with hexagonal structure and contains inorganic particles including SiO2 as a component. In addition, in the sintered magnet, the total cross-sectional area of inorganic particles each having about 0.025-100 μm2 in the cross-sectional area occupies about 0.01-3 area percent of the sintered magnet cross section. The sintered magnet contains at least one element A at about 1-13 atomic percent, which is selected from Sr, Ba, Ca and Pb and contains Sr without foil; at least one element R at about 0.05-10 atomic percent, which is selected from rare-earth elements and Bi and contains La without foil; an element M at about 0.1-5 atomic percent, which is selected from Co or Co-Zn, or Fe at about 80-95 atomic percent. |
