| 摘要 |
PURPOSE:To prevent deterioration of characteristics of product by firing a molded item of Mn-Zn based ferrite while surrounding with a furnace material made of ZnAl2O4 and placing ZnO powder therein thereby restraining the scattering of zinc component from the surface of core. CONSTITUTION:When a molded item of Mn-Zn based ferrite is fired, it is surrounded by a furnace material made of ZnAl2O4 and a powder containing ZnO is sprayed thereon and between the stacked cores. In such method, The ZnO powder to be sprayed contains 30-80% of ZnO and the remainder of ZrO2. This method prevents the scattering of zinc component from the surface of ferrite core at the time of firing even after long time use and thereby prevents deterioration of magnetic characteristics thus obtaining an Mn-Zn ferrite economically. |
