| 摘要 |
PURPOSE:To make small the crystal gain size, enlarge the specific resistance and improve frequency characteristic of core loss by mixing the raw materials mainly consisting of Fe2O3 and MnO, ZnO having the primary gain size in the particular range of size in the Mn-Zn system ferrite magnetic material and a small amount of SiO2 and CaO and then sintering them after granulation and press molding. CONSTITUTION:The core loss PB is defined as indicated in the figure depending on the average grain size of Fe2O2O3 and residue SO3 and the grain size of raw material Fe2O3 is in the range of 0.08-0.15mum and the core loss PB becomes as low as within 500kW/m<2> with the content of SO3 of 0.2-0.3wt%. In case the granularity of Fe2O3 raw material is small, the crystal becomes large by the sintering and if granularity is too large, density is lowered. In any case, core loss becomes large. Therefore, it is desirable that granularity is set to 0.08 to 0.15Xm. Moreover, content of SO3 in Fe2O3 is excessive, it interferes the sintering reaction, but if it is too short, it gives adverse effect on the reaction. In case a preliminary sintering is not carried out, it gives large influence and it is no longer possible to improve core loss.
|
