摘要 |
PURPOSE:To contrive the reduction of power loss in a specific temperature region, by compositely adding a specific amount of CaO, Nb2O5 and SiO2 as the sub component to the ferrite powder of MnO, ZnO Fe2O3 as the main component. CONSTITUTION:To MnO, ZnO and Fe2O3 as the main component, CaO in 0.04- 0.2wt%, Nb2O5 in 0.1wt% or less (not including 0) and SiO2 in 0.05wt% or less (not including 0) are added as the sub component so that they are contained. When CaO becomes more than 0.2wt%, a ferrite sintered body with the lack of sintering is formed, and, when less than 0.04wt%, the natural resistance of the sintered body decreases too much resulting in the deterioration of the frequency characteristic. When Nb2O5 becomes more than 0.1wt%, an inhomogeneous crystal grain growth is caused resulting in the deterioration of te magnetic characteristic, and, when SiO2 becomes more than 0.05wt%, likewise, the magnetic characteristic deteriorates. Thereby, the power loss before and after 60- 80 deg.C can be extremely reduced. |