Mn-zn ferrite and production process thereof
AssigneeMinebea Co., Ltd.
InventorsOsamu Kobayashi, Osamu Yamada, Kiyoshi Ito
Life of this patent
Estimating the term…
Abstract
The present invention provides a Mn—Zn ferrite having an electrical resistivity exceeding 1 Ωm order and a low core loss in a high frequency region exceeding 1 MHz. A basic component composition of the Mn—Zn ferrite includes 44.0 to 49.8 mol % of Fe2O3, 6.0 to 15.0 mol % of ZnO (15.0 mol % is excluded), 0.1 to 3.0 mol % of CoO, 0.02 to 1.20 mol % of Mn2O3, and the remainder of MnO. The Mn—Zn ferrite achieves desired purposes by controlling Fe2O3 content to a range less than 50 mol % that is the stoichiometric composition, adding a proper amount of CoO, restraining amount of Mn2O3 formation to 1.20 mol % or less, and further setting their average grain sizes to less than 10 μm.
Claims4
A Mn—Zn ferrite, characterized in that its basic component composition comprises:
- 44.0 to 49.8 mol % of Fe2O3;
- 6.0 to 15.0 mol % of ZnO (15.0 mol % is excluded);
- 0.1 to 3.0 mol % of CoO;
- 0.02 to 1.20 mol % of Mn2O3;
- and remainder of MnO, and that its average grain size is less than 10 μm.
A Mn—Zn ferrite, characterized in that its basic component composition comprises:
- 44.0 to 49.8 mol % of Fe2O3;
- 6.0 to 15.0 mol % of ZnO (15.0 mol % is excluded);
- 0.1 to 3.0 mol % of CoO;
- 0.1 to 6.0 mol % of CuO;
- 0.02 to 1.20 mol % of Mn2O3;
- and remainder of MnO, and that its average grain size is less than 10 μm.
Dependencies are inferred from the claim text.