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 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 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 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 method for producing a sintered magnet comprising steps of; wet-pulverizing a magnetic powder under the presence of a surface active agent, drying said wet-pulverized magnetic powder 20 for obtaining magnetic powder to which said surface active agent is adhered, heating and kneading said dried magnetic powder 20 with binder resin to form pellet, melting said pellet and injecting said pellet in a mold to which magnetic field is applied, to form a preform body, and firing said preform body.

Abstract: The present invention provides a ferrite magnetic material capable of attaining such magnetic properties that Br+(?)HcJ is 6200 or more even by sintering at a temperature of 1150° C. or lower. The ferrite magnetic material includes as a main phase thereof a ferrite phase having a hexagonal structure, the main phase being represented by the following composition formula (1): LaxCam?1?x?m(Fe12?yCoy)z with ? representing one or two of Ba and Sr; wherein the constituent ratios of the metal elements constituting the main phase satisfy the following conditions: x and m are the values in a region bounded by the points, A: (0.53, 0.27), B: (0.64, 0.27), C: (0.64, 0.35), D: (0.53, 0.45), E: (0.47, 0.45) and F: (0.47, 0.32) in the (x, m) coordinates shown in FIG. 2; 1.3?x/yz?1.8; and 9.5?12z?11.0.

Abstract: A ferrite magnet powder is represented by the composition formula AFe2+a(1-x)MaxFe3+bO27, wherein A represents at least one element selected from the group consisting of Sr, Ba, and Pb; and M represents at least one element selected from the group consisting of Zn, Co, Mn, and Ni, and wherein 0.05?x?0.80, 1.5?a?2.2, and 12?b?17. A high saturation magnetization 4?Is can be achieved by the partial substitution of the Fe2+ site of a W-type ferrite with an element M such as Zn within a certain range.

Abstract: W-type ferrite has improved magnetic properties, in particular, coercive force. A high coercive force (HcJ) and a high residual magnetic flux density (Br) can be simultaneously attained by a ferrite magnetic material comprising an oxide having a composition wherein metal elements Sr, Ba and Fe in total have a composition ratio represented by the formula Sr(1?x)BaxFe2+aFe3+b in which 0.03 ?x?0.80, 1.1?a?2.4, and 12.3?b?16.1. The ferrite magnetic material can form any of a ferrite sintered magnet, a ferrite magnet powder, a bonded magnet as a ferrite magnet powder dispersed in a resin, and a magnetic recording medium as a film-type magnetic phase. As for the ferrite sintered magnet, there can be attained a fine sintered structure that has a mean grain size of 0.6 ?m or less.

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.

Abstract: A method for producing a sintered magnet comprising steps of; wet-pulverizing a magnetic powder under the presence of a surface active agent, drying said wet-pulverized magnetic powder 20 for obtaining magnetic powder to which said surface active agent is adhered, heating and kneading said dried magnetic powder 20 with binder resin to form pellet, melting said pellet and injecting said pellet in a mold to which magnetic field is applied, to form a preform body, and firing said preform body.

Abstract: A ferrite magnetic material comprising a main phase of W-type is provided which has magnetic properties improved through the optimization of additives. The ferrite magnetic material comprises a main constituent having a compound represented by composition formula AFe2+aFe3+bO27 (wherein A comprises at least one element selected from Sr, Ba and Pb; 1.5?a?2.1; and 12.9?b?16.3), a first additive containing a Ca constituent (0.3 to 3.0 wt % in terms of CaCO3) and/or a Si constituent (0.2 to 1.4 wt % in terms of SiO2), and a second additive containing at least one of an Al constituent (0.01 to 1.5 wt % in terms of Al2O3), a W constituent (0.01 to 0.6 wt % in terms of WO3), a Ce constituent (0.001 to 0.6 wt % in terms of CeO2), a Mo constituent (0.001 to 0.16 wt % in terms of MoO3), and a Ga constituent (0.001 to 15 wt % in terms of Ga2O3).

Abstract: There is provided a process for producing W-type ferrite having high magnetic properties by reducing compacting defects during wet compacting. Specifically, there is a provided a process for producing a ferrite sintered body having a main composition of the following formula (1): AFe2+aFe3+bO27 . . . (1) wherein 1.5?a?2.1, 14?a+b?18.

Abstract: The present invention provides a ferrite magnet material comprising, as a main phase, a ferrite having a hexagonal structure, the main phase containing A, La, R, Fe and Co, wherein A is at least one element selected from Sr, Ba and Pb, R is Pr and/or Nd, and the proportions of the total metal elements A, La, R, Fe and Co in the main phase are respectively A: 1 to 13 atomic %, La: 0.003 to 10 atomic %, R: 0 to 10 atomic % (excluding 0) Fe: 80 to 95 atomic % and Co: 0.05 to 5 atomic % based on the total amounts of metal elements. The residual magnetic flux density Br and coercive force HcJ can be improved without increasing the content of Co by incorporating Pr and/or Nd along with La and Co in the ferrite magnet material.

Abstract: W-type ferrite has improved magnetic properties, in particular, coercive force. A high coercive force (HcJ) and a high residual magnetic flux density (Br) can be simultaneously attained by a ferrite magnetic material comprising an oxide having a composition wherein metal elements Sr, Ba and Fe in total have a composition ratio represented by the formula Sr(1?x)BaxFe2+aFe3+b in which 0.03?x?0.80, 1.1?a?2.4, and 12.3?b?16.1. The ferrite magnetic material can form any of a ferrite sintered magnet, a ferrite magnet powder, a bonded magnet as a ferrite magnet powder dispersed in a resin, and a magnetic recording medium as a film-type magnetic phase. As for the ferrite sintered magnet, there can be attained a fine sintered structure that has a mean grain size of 0.6 ?m or less.

Abstract: The present invention provides a ferrite magnetic material capable of attaining such magnetic properties that Br+(?)HcJ is 6200 or more even by sintering at a temperature of 1150° C. or lower. The ferrite magnetic material includes as a main phase thereof a ferrite phase having a hexagonal structure, the main phase being represented by the following composition formula (1): LaxCam?1?x?m(Fe12?yCoy)z with ? representing one or two of Ba and Sr; wherein the constituent ratios of the metal elements constituting the main phase satisfy the following conditions: x and m are the values in a region bounded by the points, A: (0.53, 0.27), B: (0.64, 0.27), C: (0.64, 0.35), D: (0.53, 0.45), E: (0.47, 0.45) and F: (0.47, 0.32) in the (x, m) coordinates shown in FIG. 2; 1.3?x/yz?1.8; and 9.5?12z?11.0.

Abstract: A ferrite magnetic material comprising a main phase of W-type is provided which has magnetic properties improved through the optimization of additives. The ferrite magnetic material comprises a main constituent having a compound represented by composition formula AFe2+aFe3+bO27 (wherein A comprises at least one element selected from Sr, Ba and Pb; 1.5?a?2.1; and 12.9?b?16.3), a first additive containing a Ca constituent (0.3 to 3.0 wt % in terms of CaCO3) and/or a Si constituent (0.2 to 1.4 wt % in terms of SiO2), and a second additive containing at least one of an Al constituent (0.01 to 1.5 wt % in terms of Al2O3), a W constituent (0.01 to 0.6 wt % in terms of WO3), a Ce constituent (0.001 to 0.6 wt % in terms of CeO2), a Mo constituent (0.001 to 0.16 wt % in terms of MoO3), and a Ga constituent (0.001 to 15 wt % in terms of Ga2O3).

Abstract: The present invention provides a ferrite magnetic material comprising as a main constituent a compound represented by a composition formula, AFe2+aFe3+bO27 (wherein 1.1?a?2.4, 12.3?b?16.1; and A comprises at least one element selected from Sr, Ba and Pb), and also comprising as additives a Ca constituent in terms of CaCO3 and a Si constituent in terms of SiO2 so as to satisfy the relation CaCO3/SiO2=0.5 to 1.38 (molar ratio). By making the relation CaCO3/SiO2=0.5 to 1.38 (molar ratio) be satisfied, the coercive force (HcJ) and the residual magnetic flux density (Br) can be made to simultaneously attain high levels.

Abstract: A ferrite magnet powder is represented by the composition formula AFe2+a(1-x)MaxFe3+bO27, wherein A represents at least one element selected from the group consisting of Sr, Ba, and Pb; and M represents at least one element selected from the group consisting of Zn, Co, Mn, and Ni, and wherein 0.05?x?0.80, 1.5?a?2.2, and 12?b?17. A high saturation magnetization 4?Is can be achieved by the partial substitution of the Fe2+ site of a W-type ferrite with an element M such as Zn within a certain range.

Abstract: The present invention provides a ferrite magnet material comprising, as a main phase, a ferrite having a hexagonal structure, the main phase containing A, La, R, Fe and Co, wherein A is at least one element selected from Sr, Ba and Pb, R is Pr and/or Nd, and the proportions of the total metal elements A, La, R, Fe and Co in the main phase are respectively A: 1 to 13 atomic %, La: 0.003 to 10 atomic %, R: 0 to 10 atomic % (excluding 0) Fe: 80 to 95 atomic % and Co: 0.05 to 5 atomic % based on the total amounts of metal elements. The residual magnetic flux density Br and coercive force HcJ can be improved without increasing the content of Co by incorporating Pr and/or Nd along with La and Co in the ferrite magnet material.

Abstract: The present invention provides an oxide magnetic material, which includes a primary phase of a hexagonal ferrite containing metallic elements Ca, R, Fe and M, where M represents at least one element selected from the group including Co, Ni and Zn, and R represents at least one element selected from the group including Bi and rare earth elements including Y, with La being essentially included in R; wherein the proportions of the metallic elements Ca, R, Fe and M with respect to the total amount of the metallic elements are from 1 to 13 atomic % for Ca, from 0.05 to 10 atomic % for R, from 80 to 95 atomic % for Fe, and from 1 to 7 atomic % for M. The present invention also provides ferrite particles, a bonded magnet, a sintered magnet, a process for producing them, and a magnetic recording medium, which contain the oxide magnetic material.