Abstract: A Sm—Fe—N magnet includes Sm—Fe—N particles, wherein an inter-particle metal phase is present between at least two of the Sm—Fe—N particles, an average particle diameter of the Sm—Fe—N particles is less than 2.0 ?m, and a percentage of the Sm—Fe—N particles having an aspect ratio of 2.0 or more is 10% or less, the inter-particle metal phase includes a Fe3Zn10 phase and an ?-Fe phase in a particle form, and in the inter-particle metal phase, an area ratio of the Fe3Zn10 phase is 80% or more.

Abstract: To provide a rare earth permanent magnet having as a main phase a compound with a Nd5Fe17 crystalline structure having strong coercive force. A rare earth permanent magnet having as a main phase a compound with a Nd5Fe17 crystalline structure, wherein when the composition ratio of the rare earth permanent magnet is expressed as RaT(100-a-b)Cb, where R is one or more rare earth elements requiring Sm, and T is one or more transition metal elements requiring Fe or Fe and Co, a and b satisfy 18<a<40 and 0.5?b, and a phase where R and C are denser than the main phase is provided in the grain boundary phase of the rare earth permanent magnet.

Abstract: A rare earth permanent magnet that is high in residual magnetization and coercivity is obtained and includes R and T. A main phase of crystal grains having an Nd5Fe17 type crystal structure is included. In an X-ray diffraction profile drawn by performing an XRD measurement for a rare earth permanent magnet, peaks of detected intensity are present in specific ranges. In which the detected intensity of the peak with the highest detected intensity in the range of 41.60°<2?(°)<42.80° is set as ?, the detected intensity of the peak with the highest detected intensity in the range of 34.38°<2?(°)<34.64° is set as ?, and the detected intensity of the peak with the highest detected intensity in the range of 38.70°<2?(°)<41.20° is set as ?, 0.38<?/?<0.70 and 0.45<?/?<0.70 are established. The peak with the highest detected intensity in the range of 34.38°<2?(°)<34.64° is a peak derived from the Nd5Fe17 type crystal structure.

Abstract: To provide a rare earth permanent magnet having as a main phase a compound with a Nd5Fe17 crystalline structure having strong coercive force. A rare earth permanent magnet having as a main phase a compound with a Nd5Fe17 crystalline structure, wherein when the composition ratio of the rare earth permanent magnet is expressed as RaT(100-a-b)Cb, where R is one or more rare earth elements requiring Sm, and T is one or more transition metal elements requiring Fe or Fe and Co, a and b satisfy 18<a<40 and 0.5?b, and a phase where R and C are denser than the main phase is provided in the grain boundary phase of the rare earth permanent magnet.

Abstract: A rare earth permanent magnet that is high in residual magnetization and coercivity is obtained and includes R and T. A main phase of crystal grains having an Nd5Fe17 type crystal structure is included. In an X-ray diffraction profile drawn by performing an XRD measurement for a rare earth permanent magnet, peaks of detected intensity are present in specific ranges. In which the detected intensity of the peak with the highest detected intensity in the range of 41.60°<2?(°)<42.80° is set as ?, the detected intensity of the peak with the highest detected intensity in the range of 34.38°<2?(°)<34.64° is set as ?, and the detected intensity of the peak with the highest detected intensity in the range of 38.70°<2?(°)<41.20° is set as ?, 0.38<?/?<0.70 and 0.45<?/?<0.70 are established. The peak with the highest detected intensity in the range of 34.38°<2?(°)<34.64° is a peak derived from the Nd5Fe17 type crystal structure.

Abstract: A permanent magnet having a periodic structure with the concentrations of Fe and T (T is one or more transition metal elements with Co or Ni as necessity) changing alternately, wherein, the concentrations change with a period of 3.3 nm or less and the concentration difference of Fe in the concentration change is 5 at % or more. The permanent magnet has a high saturation magnetization Is and coercivity HcJ and can be prepared even without rare earth element(s) R.

Abstract: A permanent magnet having a periodic structure with the concentrations of Fe and T (T is one or more transition metal elements with Co or Ni as necessity) changing alternately, wherein, the concentrations change with a period of 3.3 nm or less and the concentration difference of Fe in the concentration change is 5 at % or more. The permanent magnet has a high saturation magnetization Is and coercivity HcJ and can be prepared even without rare earth element(s) R.

Abstract: The present invention provides a production method of a ferrite material comprising as main constituents Fe2O3: 62 to 68 mol %, ZnO: 12 to 20 mol %, and MnO substantially constituting the balance, wherein the method comprises a compacting step for obtaining a compacted body by using a powder containing the main constituents, the powder having a specific surface area falling within a range between 2.5 and 5.0 m2/g and a 90% particle size of 10 ?m or less, and a sintering step for sintering the compacted body obtained in the compacting step. Accordingly, the saturation magnetic flux density of the Mn—Zn based ferrite can be improved.

Abstract: The present invention provides a Mn—Zn ferrite which is low in the loss in the frequency range between a few 10 kHz and a few 100 kHz and high in the saturation magnetic flux density in the vicinity of 100° C. The present invention comprising the steps of compacting a powder having a specific surface area (based on the BET method) of 2.0 to 5.0 m2/g and a 50% particle size of 0.7 to 2.0 ?m into a compacted body having a predetermined shape and obtaining a sintered body by sintering the compacted body. It is preferable that a Mn—Zn ferrite comprises, as main constituents, 54 to 57 mol % of Fe2O3, 5 to 10 mol % of ZnO, 4 mol % or less (not inclusive of 0%) of NiO, and the balance substantially being MnO.

Abstract: A Mn—Zn based ferrite sintered body containing 62 to 68 mol % of Fe2O3 and 12 to 20 mol % of ZnO is made to contain, as main constituents, NiO and/or LiO0.5. Additionally, a Mn—Zn based ferrite sintered body containing 62 to 68 mol % of Fe2O3 and 12 to 23 mol % of ZnO is made to contain, as additives, Si and Ca. This sintered body can achieve such properties that the saturation magnetic flux density at 100° C. is 450 mT or more (magnetic field for measurement: 1194 A/m), the minimum core loss value is 1200 kW/m3 or less (measurement conditions: 100 kHz, 200 mT), the bottom temperature at which the minimum core loss value is exhibited is from 60 to 130° C., and the initial permeability at room temperature is 700 or more.

Abstract: The present invention provides a production method of a ferrite material comprising as main constituents Fe2O3: 62 to 68 mol %, ZnO: 12 to 20 mol %, and MnO substantially constituting the balance, wherein the method comprises a compacting step for obtaining a compacted body by using a powder containing the main constituents, the powder having a specific surface area falling within a range between 2.5 and 5.0 m2/g and a 90% particle size of 10 ?m or less, and a sintering step for sintering the compacted body obtained in the compacting step. Accordingly, the saturation magnetic flux density of the Mn—Zn based ferrite can be improved.

Abstract: The present invention provides a Mn—Zn ferrite which is low in the loss in the frequency range between a few 10 kHz and a few 100 kHz and high in the saturation magnetic flux density in the vicinity of 100° C. The present invention comprising the steps of compacting a powder having a specific surface area (based on the BET method) of 2.0 to 5.0 m2/g and a 50% particle size of 0.7 to 2.0 ?m into a compacted body having a predetermined shape and obtaining a sintered body by sintering the compacted body. It is preferable that a Mn—Zn ferrite comprises, as main constituents, 54 to 57 mol % of Fe2O3, 5 to 10 mol % of ZnO, 4 mol % or less (not inclusive of 0%) of NiO, and the balance substantially being MnO.