Abstract: Provided are a rare-earth magnet capable of realizing a high magnetic flux amount without using any back yoke, and a linear motor comprising a movable element using the rare-earth permanent magnet. A rare-earth permanent magnet-forming sintered body for forming a permanent magnet is integrally sintered while being formed into a given three-dimensional shape with a lengthwise cross-section having a first surface extending in a length direction thereof, a second surface lying at a distance from the first surface in a thickness direction thereof and extending in the length direction, and an edge surface of each of lengthwise opposite ends thereof. This sintered body is formed such that easy magnetization axes of the magnet material particles included in a central region thereof are oriented in such a manner as to be directed along an arch-shaped path.

Abstract: Provided is a method for producing a sintered body that forms a rare-earth permanent magnet, has a single sintered structure and an arbitrary shape, and has easy magnetization axis orientations of different directions applied to the magnet material particles in a plurality of arbitrary regions. This method forms a three-dimensional first molded article from a composite material formed by mixing a resin material and magnet material particles containing a rare-earth substance. The first molded article is then subjected to a deforming force and a second molded article is formed in which the orientation direction of the easy magnetization axis of the magnet material particles in at least the one section of the horizontal cross-section is changed to a direction which differs from the orientation direction of the first molded article. The second molded article is heated to a sintering temperature and kept at the temperature for a period of time.

Abstract: Provided is a method for producing a sintered body that forms a rare-earth permanent magnet, has a single sintered structure and an arbitrary shape, and has easy magnetization axis orientations of different directions applied to the magnet material particles in a plurality of arbitrary regions. This method forms a three-dimensional first molded article from a composite material formed by mixing a resin material and magnet material particles containing a rare-earth substance. The first molded article is then subjected to a deforming force and a second molded article is formed in which the orientation direction of the easy magnetization axis of the magnet material particles in at least the one section of the horizontal cross-section is changed to a direction which differs from the orientation direction of the first molded article. The second molded article is heated to a sintering temperature and kept at the temperature for a period of time.

Abstract: Provided are a rare-earth magnet capable of realizing a high magnetic flux amount without using any back yoke, and a linear motor comprising a movable element using the rare-earth permanent magnet. A rare-earth permanent magnet-forming sintered body for forming a permanent magnet is integrally sintered while being formed into a given three-dimensional shape with a lengthwise cross-section having a first surface extending in a length direction thereof, a second surface lying at a distance from the first surface in a thickness direction thereof and extending in the length direction, and an edge surface of each of lengthwise opposite ends thereof. This sintered body is formed such that easy magnetization axes of the magnet material particles included in a central region thereof are oriented in such a manner as to be directed along an arch-shaped path.

Abstract: Raw material magnet is milled to magnet powder, and the magnet powder thus milled is mixed with a binder to form a compound 12. Then, the compound 12 thus formed is molded to a green sheet 14 having a sheet shape. Thereafter, a magnetic field orientation is carried out by applying a magnetic field to the green sheet 14 thus molded, and then, the green sheet 14 having been subjected to the magnetic field orientation is shaped to a product shape by deforming thereof. Thereafter, the permanent magnet 1 is produced by sintering thereof. The permanent magnet 1 has a ring shape, and is constituted such that an axis of easy magnetization may be orientated at a slant so as to converge in a direction along a converging axis P which is set to a radius direction as well as to a center direction of the ring shape.

Abstract: The present invention relates to a permanent magnet obtained by wet-mixing a Dy compound or a Tb compound with a magnet raw material to coat a surface of the magnet raw material with the Dy compound or the Tb compound, and sintering a green sheet obtained by mixing the resulting magnet raw material with a resin binder and molding the resulting mixture. Since the present invention has the above-mentioned constitution, it becomes possible to sufficiently improve coercive force by Dy or Tb while decreasing the amount of Dy or Tb used. Further, it can be prevented that Dy or Tb is solid-solutionized in magnet particles to decrease residual magnetization.

Abstract: A method for producing a permanent magnet for a motor, including a step of producing a slurry of a magnet powder, a step of molding the slurry into a sheet form to prepare green sheets of the magnet powder, and a step of alternately laminating the green sheets of the magnet powder and an insulating layer and sintering the laminated plural layers.

Abstract: There are provided a permanent magnet and a manufacturing method thereof capable of decreasing an activity level of a calcined body activated by a calcination process. To fine powder of milled neodymium magnet is added an organometallic compound solution containing an organometallic compound expressed with a structural formula of M?(OR)x (M represents Dy or Tb, R represents a substituent group consisting of a straight-chain or branched-chain hydrocarbon, x represents an arbitrary integer) so as to uniformly adhere the organometallic compound to particle surfaces of the neodymium magnet powder. Thereafter, desiccated magnet powder is held for several hours in hydrogen atmosphere at 200 through 900 degrees Celsius. Thereafter, the powdery calcined body calcined through the calcination process in hydrogen is held for several hours in vacuum atmosphere at 200 through 600 degrees Celsius for a dehydrogenation process.

Abstract: The present invention relates to a permanent magnet manufactured by steps of: pulverizing a magnet raw material into fine particles having a grain size of 3 ?m or less; mixing the pulverized magnet raw material with a rust preventive oil in which a high-melting metal element-containing organic compound or a precursor of a high-melting ceramic is dissolved, thereby preparing a slurry; compression molding the slurry to form a molded body; and sintering the molded body.

Abstract: The present invention relates to a permanent magnet manufactured by steps of: wet-pulverizing a high-melting metal element-containing organic compound or a precursor of a high-melting ceramic in a solvent together with a magnet raw material to pulverize the magnet raw material into fine particles having a grain size of 3 ?m or less and to coat a surface of the pulverized magnet raw material with the high-melting metal element-containing organic compound or the precursor of the high-melting ceramic; adding a resin binder to the magnet raw material coated with the high-melting metal element-containing organic compound or the precursor of the high-melting ceramic; producing a slurry by kneading the magnet raw material and the resin binder; molding the slurry into a sheet form to prepare a green sheet; and sintering the green sheet.

Abstract: There are provided a permanent magnet and a manufacturing method thereof capable of densely sintering the entirety of the magnet without making a gap between a main phase and a grain boundary phase in the sintered magnet. To fine powder of milled neodymium magnet is added an organometallic compound solution containing an organometallic compound expressed with a structural formula of M-(OR)X (M represents Dy or Tb, R represents a substituent group consisting of a straight-chain or branched-chain hydrocarbon, X represents an arbitrary integer) so as to uniformly adhere the organometallic compound to particle surfaces of the neodymium magnet powder. Thereafter, a compact body formed by powder compaction is held for several hours in hydrogen atmosphere at 200 through 900 degrees Celsius for calcination process in hydrogen. Thereafter, through sintering process, the compacted-state calcined body is formed into a permanent magnet.

Abstract: There are provided a permanent magnet and a manufacturing method thereof capable of decreasing an activity level of a calcined body activated by a calcination process. To fine powder of milled neodymium magnet is added an organometallic compound solution containing an organometallic compound expressed with a structural formula of M?(OR)x (M represents Dy or Tb, R represents a substituent group consisting of a straight-chain or branched-chain hydrocarbon, x represents an arbitrary integer) so as to uniformly adhere the organometallic compound to particle surfaces of the neodymium magnet powder. Thereafter, desiccated magnet powder is held for several hours in hydrogen atmosphere at 200 through 900 degrees Celsius. Thereafter, the powdery calcined body calcined through the calcination process in hydrogen is held for several hours in vacuum atmosphere at 200 through 600 degrees Celsius for a dehydrogenation process.

Abstract: There are provided a permanent magnet and a manufacturing method thereof capable of densely sintering the entirety of the magnet without making a gap between a main phase and a grain boundary phase in the sintered magnet. To fine powder of milled neodymium magnet is added an organometallic compound solution containing an organometallic compound expressed with a structural formula of M-(OR)X (M represents Dy or Tb, R represents a substituent group consisting of a straight-chain or branched-chain hydrocarbon, X represents an arbitrary integer) so as to uniformly adhere the organometallic compound to particle surfaces of the neodymium magnet powder. Thereafter, desiccated magnet powder is held for several hours in hydrogen atmosphere at 200 through 900 degrees Celsius. Thereafter, the powdery calcined body calcined through the calcination process in hydrogen is held for several hours in vacuum atmosphere at 200 through 600 degrees Celsius for a dehydrogenation process.

Abstract: There are provided a permanent magnet and a manufacturing method thereof capable of efficiently concentrating traces of Dy or Tb in grain boundaries of the magnet and sufficiently improving coercive force due to Dy or Tb while reducing amount of Dy or Tb to be used. To fine powder of milled neodymium magnet material is added an organometallic compound solution containing an organometallic compound expressed with a structural formula of M-(OR)x (M represents Dy or Tb, R represents a substituent group consisting of a straight-chain or branched-chain hydrocarbon, x represents an arbitrary integer) so as to uniformly adhere the organometallic compound to particle surfaces of the neodymium magnet powder. Thereafter, a compact body compacted through powder compaction is held for several hours in hydrogen atmosphere at 200 through 900 degrees Celsius for a hydrogen calcination process. Thereafter, through sintering process, the compact body is formed into a permanent magnet.

Abstract: The present invention relates to a permanent magnet manufactured by steps of: pulverizing a magnet raw material into fine particles having a grain size of 3 ?m or less; mixing the pulverized magnet raw material with a rust preventive oil in which a high-melting metal element-containing organic compound or a precursor of a high-melting ceramic is dissolved, thereby preparing a slurry; compression molding the slurry to form a molded body; and sintering the molded body.

Abstract: An electromagnetic radiation absorber is made up of a composite of base material and filler. The base material is formed of high permittivity dielectric material and formed in a cubic shape. The filler is formed of high magnetic permeability material and fills in long holes formed inside the base material in three directions. In the composite, the high permittivity dielectric material and the high magnetic permeability material are arranged in a three-dimensionally continuous manner. Accordingly, a thinned and light-weighted electromagnetic radiation absorber and a method for absorbing electromagnetic radiation are provided which have a high electromagnetic radiation absorbing property with respect to electromagnetic radiation of wide band including electromagnetic radiation of low frequency.

Abstract: The present invention relates to a permanent magnet manufactured by steps of: pulverizing a magnet raw material; mixing the pulverized magnet raw material with a rust preventive oil in which a Dy compound or a Tb compound is dissolved, thereby preparing a slurry; compression molding the slurry to form a molded body; and sintering the molded body.

Abstract: The present invention relates to a permanent magnet manufactured by steps of: wet-pulverizing a high-melting metal element-containing organic compound or a precursor of a high-melting ceramic in a solvent together with a magnet raw material to pulverize the magnet raw material into fine particles having a grain size of 3 ?m or less and to coat a surface of the pulverized magnet raw material with the high-melting metal element-containing organic compound or the precursor of the high-melting ceramic; adding a resin binder to the magnet raw material coated with the high-melting metal element-containing organic compound or the precursor of the high-melting ceramic; producing a slurry by kneading the magnet raw material and the resin binder; molding the slurry into a sheet form to prepare a green sheet; and sintering the green sheet.

Abstract: The present invention relates to a permanent magnet obtained by wet-mixing a Dy compound or a Tb compound with a magnet raw material to coat a surface of the magnet raw material with the Dy compound or the Tb compound, and sintering a green sheet obtained by mixing the resulting magnet raw material with a resin binder and molding the resulting mixture. Since the present invention has the above-mentioned constitution, it becomes possible to sufficiently improve coercive force by Dy or Tb while decreasing the amount of Dy or Tb used. Further, it can be prevented that Dy or Tb is solid-solutionized in magnet particles to decrease residual magnetization.

Abstract: The present invention relates to a permanent magnet for a motor, to be buried in a permanent magnet motor, including: a plurality of sheet magnets for lamination, and an insulating layer arranged between the plurality of sheet magnets for lamination. Since the invention has the above-mentioned constitution, the permanent magnets are free from the problems of temperature elevation and coercive force depression, therefore making it possible to provide a high-power small-sized motor. Furthermore, it is unnecessary to perform the conventional correcting processing after sintering, which can simplify the production steps, and therefore, it becomes possible to mold the permanent magnet with a high degree of dimension accuracy.