Abstract: A sintered ferrite magnet comprises a main phase of an M type Sr ferrite having a hexagonal crystal structure. An amount of Zn is 0.05 to 1.35 mass % in terms of ZnO and M1/M2 is 0.43 or less when an amount of a rare-earth element (R) is M1 in terms of mol and the amount of Zn is M2 in terms of mol.

Abstract: A sintered ferrite magnet comprises a main phase of an M type Sr ferrite having a hexagonal crystal structure. An amount of Zn is 0.05 to 1.35 mass % in terms of ZnO, the sintered ferrite magnet does not substantially include a rare-earth element (R), and the following Formula (1) is satisfied, where a total amount of Sr, Ba and Ca is M3 in terms of mol, a total amount of Fe, Co, Mn, Zn, Cr and Al is M4 in terms of mol, and an amount of Si is M5 in terms of mol. 0.5?{M3?(M4/12)}/M5?4.8??(1).

Abstract: An object of the present invention is to provide a ferrite magnetic material which can provide a permanent magnet retaining high Br and HcJ as well as having high Hk/HcJ. The ferrite magnetic material according to a preferred embodiment is a ferrite magnetic material formed of hard ferrite, wherein a P content in terms of P2O5 is 0.001% by mass or more.

Abstract: An injection molding composition includes a ferrite powder which is a collection of ferrite particles, a first binder and a second binder, wherein a softening point of the second binder is lower than that of the first binder, a weight and a specific surface area of the ferrite powders are represented by Wp and S, and a weight and a density of the first binder and the second binder is represented by Wb1, Wb2, and Db1, Db2, and a hypothetical thickness Tb1 of the first binder is 0.6 to 3.0, and a hypothetical thickness Tb2 of the second binder is 5.0 to 16.0. In the composition, it is preferable that coated ferrite particles covering the outer circumference of the ferrite particles with the first binder and the second binder exist. Tb1 [nm]=(Wb1×103)/(Db1×Wp×S)??formula (1) Tb2 [nm]=(Wb2×103)/(Db2×Wp×S)??formula (2).

Abstract: An object of the present invention is to provide a ferrite magnetic material capable of providing a permanent magnet in which high Br and HcJ are kept, and which has a high Hk/HcJ. A ferrite magnetic material in accordance with a preferred embodiment has a ferrite phase having a hexagonal structure and has a main composition represented by Ca1-w-x-yRwSrxBayFezMmO19 (R is at least one element of rare earth elements (including Y) essentially including La, and Bi, and M is at least one element of Co, Mn, Mg, Ni, Cu, and Zn essentially including Co), where 0.25<w<0.65, 0.01<x<0.45, 0.0002<y<0.011, y<x, 8<z<11, 1.0<w/m<2.5, and 0.017<m/z<0.065 are satisfied. The total amount of a Si component is 0.1 to 3 mass % based on the amount of the main composition, and respective elements satisfy the relationship of 1.5?[(Ca+R+Sr+Ba)?(Fe+M)/12]/Si?3.5.

Abstract: A ferrite magnet and a ferrite sintered magnet including a ferrite magnetic material are provided. A main phase of the ferrite magnetic material includes a ferrite phase having a hexagonal crystal structure, and metal element composition expressed by Ca1-w-x-yR wSr xBayFezMm wherein 0.25<w<0.5, 0.01<x<0.35, 0.0001<y<0.013, y<x, 8.7<z<9.9, 1.0<w/m<2.1, 0.017<m/z<0.055 and Si component is at least included as a sub-component, and wherein; when content y1 mass % of the Si component in the ferrite magnetic material, with respect to SiO2, is shown on Y-axis and a total content x1 of z and m is shown on X-axis, a relation between x1 and y1 is within a range surrounded by 4 points placed on X-Y coordinate having the X and Y axes.

Abstract: A sintered ferrite magnet comprises a main phase of an M type Sr ferrite having a hexagonal crystal structure. An amount of Zn is 0.05 to 1.35 mass % in terms of ZnO and M1/M2 is 0.43 or less when an amount of a rare-earth element (R) is M1 in terms of mol and the amount of Zn is M2 in terms of mol.

Abstract: A sintered ferrite magnet comprises a main phase of an M type Sr ferrite having a hexagonal crystal structure. An amount of Zn is 0.05 to 1.35 mass % in terms of ZnO, the sintered ferrite magnet does not substantially include a rare-earth element (R), and the following Formula (1) is satisfied, where a total amount of Sr, Ba and Ca is M3 in terms of mol, a total amount of Fe, Co, Mn, Zn, Cr and Al is M4 in terms of mol, and an amount of Si is M5 in terms of mol. 0.5?{M3?(M4/12)}/M5?4.

Abstract: A ferrite magnetic material and ferrite sintered magnet composed thereof have a ferrite having a hexagonal crystal structure as a main component. A composition ratio of a metallic element included in the main component is represented by: RxA1-x(Fe12-yCoy)z. R is at least one element selected from La, Ce, Pr, Nd and Sm and at least includes La. A is at least two elements selected from Ca, Sr and Ba and at least includes Ca and Sr. Si component and either or both of Al component and Cr component are included as a sub-component. When a sum of Al content and a value obtained by dividing Cr content by four and a value obtained by calculating the formula [(R+A)?(Fe+Co)/12]/Si where R, A, Fe, Co and Si indicate values of each atom % thereof are defined as L and G, respectively, L and G have to be values within a predetermined region.

Abstract: The present invention aims to ensure strength of a thin-walled sintered magnet. A sintered magnet is a ferrite sintered magnet made by sintering a magnetic material. A magnetic powder mixture obtained by mixing magnetic powder with a binder resin is injection-molded into a mold with a magnetic field applied thereto to produce a molded body, which is then sintered to produce the sintered magnet. The sintered magnet has a thickness of 3.5 mm or less in the position of center of gravity thereof. The sintered magnet has a surface roughness Rz of 0.1 ?m or more and 2.5 ?m or less. The surface roughness Rz is a 10 point average roughness.

Abstract: A sintered ferrite magnet having a ferrite phase with a hexagonal structure as the main phase, wherein the composition of the metal elements composing the main phase is represented by the following general formula (1): RxCamA1?x?m(Fe12?yMy)z: ??(1), x, m, y and z in formula (1) satisfying all of the conditions represented by the following formulas (2)-(6): 0.2?x?0.5: ??(2) 0.13?m?0.41: ??(3) 0.7x?m?0.15: ??(4) 0.18?yz?0.31: ??(5) 9.6?12z?11.8: ??(6), and wherein the density of the sintered ferrite magnet is at least 5.05 g/cm3, and the crystal grains of the sintered ferrite magnet satisfy all of the conditions represented by the following formulas (7) and (8), where L ?m is the average for the maximum value and S ?m is the average for the minimum value among the diameters passing through the center of gravity of each grains in the crystal cross-section parallel to the c-axis direction of hexagonal structures. L?0.95: ??(7) 1.8?L/S?2.5: ??(8).

Abstract: An object of the present invention is to provide a ferrite magnetic material which can provide a permanent magnet retaining high Br and HcJ as well as having high Hk/HcJ. The ferrite magnetic material according to a preferred embodiment is a ferrite magnetic material formed of hard ferrite, wherein a P content in terms of P2O5 is 0.001% by mass or more.

Abstract: An object of the present invention is to provide a ferrite magnetic material which can provide a permanent magnet retaining high Br and HcJ as well as having high Hk/HcJ. The ferrite magnetic material according to a preferred embodiment is a ferrite magnetic material formed of hard ferrite, wherein a P content in terms of P2O5 is 0.001% by mass or more.

Abstract: A ferrite sintered magnet has a surface roughness Rz of 3.5 ?m or less. A method for producing a ferrite sintered magnet includes: mixing magnetic powders with at least a binder resin to obtain a magnetic powder mixture; injection molding the magnetic powder mixture inside of a mold having a surface roughness of a surface in contact with the magnetic powder mixture of 2.0 ?m or less with a magnetic field applied to the mold, to obtain a molded body; and sintering the molded body.

Abstract: An injection molding composition, having a small fluctuation characteristic and a better characteristic, is provided. The above composition is the injection molding composition comprising a ferrite powder which is a collection of ferrite particles, a first binder and a second binder. A weight and a specific surface area of the ferrite powders are represented by Wp and S, and a weight and a density of the first binder and the second binder is represented by Wb1, Wb2, and Db1, Db2. A hypothetical thickness Tb1 of the first binder is 2.0 to 15.0, and a hypothetical thickness Tb2 of the second binder is 16.5 to 32.0. In the composition, it is preferable that coated ferrite particles coating the outer circumference of the ferrite particles with the first binder and the second binder exist.

Abstract: An injection molding composition includes a ferrite powder which is a collection of ferrite particles, a first binder and a second binder, wherein a softening point of the second binder is lower than that of the first binder, a weight and a specific surface area of the ferrite powders are represented by Wp and S, and a weight and a density of the first binder and the second binder is represented by Wb1, Wb2, and Db1, Db2, and a hypothetical thickness Tb1 of the first binder is 0.6 to 3.0, and a hypothetical thickness Tb2 of the second binder is 5.0 to 16.0. In the composition, it is preferable that coated ferrite particles covering the outer circumference of the ferrite particles with the first binder and the second binder exist.

Abstract: A ferrite magnet and a ferrite sintered magnet including a ferrite magnetic material are provided. A main phase of the ferrite magnetic material includes a ferrite phase having a hexagonal crystal structure, and metal element composition expressed by Ca1-w-x-yR wSr xBayFezMm wherein 0.25<w<0.5, 0.01<x<0.35, 0.0001<y<0.013, y<x, 8.7<z<9.9, 1.0<w/m<2.1, 0.017<m/z<0.055 and Si component is at least included as a sub-component, and wherein; when content y1 mass % of the Si component in the ferrite magnetic material, with respect to SiO2, is shown on Y-axis and a total content x1 of z and m is shown on X-axis, a relation between x1 and y1 is within a range surrounded by 4 points placed on X-Y coordinate having the X and Y axes.

Abstract: A ferrite magnet and a ferrite sintered magnet including a ferrite magnetic material are provided. A main phase of the ferrite magnetic material includes a ferrite phase having a hexagonal crystal structure, and metal element composition expressed by Ca1-w-x-yR wSr xBayFezMm wherein 0.25<w<0.5, 0.01<x<0.35, 0.0001<y<0.013, y<x, 8.7<z<9.9, 1.0<w/m<2.1, 0.017<m/z<0.055 and Si component is at least included as a sub-component, and wherein; when content y1 mass % of the Si component in the ferrite magnetic material, with respect to SiO2, is shown on Y-axis and a total content x1 of z and m is shown on X-axis, a relation between x1 and y1 is within a range surrounded by 4 points placed on X-Y coordinate having the X and Y axes.

Abstract: An injection molding composition, having a small fluctuation characteristic and a better characteristic, is provided. The above composition is the injection molding composition comprising a ferrite powder which is a collection of ferrite particles, a first binder and a second binder. A weight and a specific surface area of the ferrite powders are represented by Wp and S, and a weight and a density of the first binder and the second binder is represented by Wb1, Wb2, and Db1, Db2. A hypothetical thickness Tb1 of the first binder is 2.0 to 15.0, and a hypothetical thickness Tb2 of the second binder is 16.5 to 32.0. In the composition, it is preferable that coated ferrite particles coating the outer circumference of the ferrite particles with the first binder and the second binder exist.

Abstract: The present invention aims to ensure strength of a thin-walled sintered magnet. A sintered magnet is a ferrite sintered magnet made by sintering a magnetic material. A magnetic powder mixture obtained by mixing magnetic powder with a binder resin is injection-molded into a mold with a magnetic field applied thereto to produce a molded body, which is then sintered to produce the sintered magnet. The sintered magnet has a thickness of 3.5 mm or less in the position of center of gravity thereof. The sintered magnet has a surface roughness Rz of 0.1 or more and 2.5 ?m or less. The surface roughness Rz is a 10 point average roughness.