Ferrite material and method for producing ferrite material
AssigneeHitachi Metals, Ltd.
InventorsTomoyuki Tada, Yasuharu Miyoshi, Takeshi Yanagihara
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Abstract
The invention provides a ferrite material (ferrite sintered body, ferrite powders) having a composition formula of (1-x-y-z)(Li0.5Fe0.5)O.xZnO.y(Mn, Fe)2O3.zCuO, wherein x, y, z, and a satisfy 0.175≦x≦0.29; 0.475≦y≦0.51; 0.07≦z≦0.22; and 0.02≦a≦0.055 in a case of a=Mn/(Mn+Fe). At least one of Co oxide, Co hydroxide, and Co carbonate in an amount of 1 wt. % or less on the basis of CoO may be contained in 100 wt % of the ferrite material. The ferrite material has a normalized impedance ZN of 40000 Ω/m or more at 30 MHz and a normalized impedance ZN of 60000 Ω/m or more at 100 MHz as well as a specific resistance of 106 Ωm or more.
Claims14
A ferrite material having a composition formula of (1-x-y-z)(Li0.5Fe0.5)O.xZnO.y(Mn, Fe)2O3.zCuO, wherein x, y, z, and a satisfy 0.175≦x≦0.29;
- 0.475≦y≦0.51;
- 0.07≦z≦0.22;
- and 0.02≦a≦0.055 in a case of a=Mn/(Mn+Fe);
- wherein at least one of Co oxide, Co hydroxide and Co carbonate in an amount of 1 wt. % or less on the basis of CoO is contained in 100 wt. % of the ferrite material.
A method for producing a ferrite material, comprising the steps of:
- preparing raw material powders having a composition formula of (1-x-y-z)(Li0.5Fe0.5)O.xZnO.y(Mn, Fe)2O3.zCuO, wherein x, y, z, and a satisfy 0.175≦x≦0.29;
- 0.475≦y≦0.51;
- 0.07≦z≦0.22;
- and 0.02≦a≦0.055 in a case of a=Mn/(Mn+Fe);
- obtaining calcinated powders by calcinating the raw material powders;
- obtaining grinded powders by grinding the calcinated powders;
- obtaining a molded body by molding the grinded powders;
- obtaining a ferrite sintered body by firing the molded body;
- and
- adding at least one of Co oxide, Co hydroxide and Co carbonate, in an amount of 1 wt. % or less on the basis of CoO relative to 100 wt. % of an object material to be added, before the firing is carried out.
A method for producing a ferrite material, comprising the steps of:
- preparing raw material powders having a composition formula of (1-x-y-z)(Li0.5Fe0.5)O.xZnO.y(Mn, Fe)2O3.zCuO, wherein x, y, z, and a satisfy 0.175≦x≦0.29;
- 0.475≦y≦0.51;
- 0.07≦z≦0.22;
- and 0.02≦a≦0.055 in a case of a=Mn/(Mn+Fe);
- obtaining ferrite powders by firing the raw material powders;
- and
- adding at least one of Co oxide, Co hydroxide, and Co carbonate in an amount of 1 wt. % or less on the basis of CoO relative to 100 wt. % of an object material to be added, before the firing is carried out.
A method for producing a ferrite material, comprising the steps of:
- preparing raw material powders having a composition formula of (1-x-y-z)(Li0.5Fe0.5)O.xZnO.y(Mn, Fe)2O3.zCuO, wherein x, y, z, and a satisfy 0.175≦x≦0.29;
- 0.475≦y≦0.51;
- 0.07≦z≦0.22;
- and 0.02≦a≦0.055 in a case of a=Mn/(Mn+Fe);
- obtaining calcinated powders by calcinating the raw material powders;
- obtaining grinded powders by grinding the calcinated powders;
- obtaining ferrite powders by firing the grinded powders;
- and
- adding at least one of Co oxide, Co hydroxide and Co carbonate in an amount of 1 wt. % or less on the basis of CoO relative to 100 wt. % of an object material to be added, before the firing is carried out.
A method for producing a ferrite material, comprising the steps of:
- preparing raw material powders having a composition formula of (1-x-y-z)(Li0.5Fe0.5)O.xZnO.y(Mn, Fe)2O3.zCuO, wherein x, y, z, and a satisfy 0.175≦x≦5 0.29;
- 0.475≦y≦0.51;
- 0.07≦z≦0.22;
- and 0.02≦a≦0.055 in a case of a=Mn/(Mn+Fe);
- obtaining calcinated powders by calcinating the raw material powders;
- obtaining grinded powders by grinding the calcinated powders;
- obtaining a molded body by molding the grinded powders;
- obtaining a sintered body by firing the molded body;
- and
- obtaining ferrite powders by grinding the sintered body.
Dependencies are inferred from the claim text.