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: There are provided a rare-earth permanent magnet and a manufacturing method of a rare-earth permanent magnet capable of preventing deterioration of magnet properties. In the method, magnet material is milled into magnet powder. Next, a mixture 12 is prepared by mixing the magnet powder and a binder, and the mixture 12 is formed into a sheet-like shape to obtain a green sheet 14. Thereafter, magnetic field orientation is performed to the green sheet 14, which is then held for several hours in a non-oxidizing atmosphere at a pressure higher than normal atmospheric pressure, at 200 through 900 degrees Celsius for calcination. Thereafter, the calcined green sheet 14 is sintered at a sintering temperature. Thereby a permanent magnet 1 is manufactured.

Abstract: There are provided a rare-earth permanent magnet and a manufacturing method of a rare-earth permanent magnet capable of preventing deterioration of magnet properties. In the method, magnet material is milled into magnet powder. Next, a mixture 12 is prepared by mixing the magnet powder and a binder, and the mixture 12 is formed into a sheet-like shape to obtain a green sheet 14. Thereafter, magnetic field orientation is performed to the green sheet 14, which is then held for several hours in a non-oxidizing atmosphere at a pressure higher than normal atmospheric pressure, at 200 through 900 degrees Celsius for calcination. Thereafter, the calcined green sheet 14 is sintered at a sintering temperature. Thereby a permanent magnet 1 is manufactured.

Abstract: The present invention provides a permanent magnet unit in which insulating layers are located at positions where an eddy current can be reduced most effectively. The permanent magnet unit includes at least one insulating layer, and a plurality of permanent magnet pieces located adjacent to each other with the at least one insulating layer in between. The at least one insulating layer is located at positions defined based on a magnitude of an eddy current flowing inside a permanent magnet, corresponding to a change in a magnetic field of the permanent magnet into which a plurality of the permanent magnet pieces are integrally formed without the at least one insulating layer.

Abstract: A method comprises: charging a rare-earth magnet-forming material comprising magnet material particles into a mold, in a state in which an easy magnetization axis of each of the magnet material particles is oriented in one plane; sintering the rare-earth magnet-forming material charged in the mold by heating the rare-earth magnet-forming material to a sintering temperature while applying a given magnitude of pressing force to the rare-earth magnet-forming material, to thereby form a sintered body in which the magnet material particles are integrally sintered; and then subjecting the sintered body to high-temperature heat treatment, under a pressure lower than the pressing force during the sintering and under a maximum achieving temperature which ranges from greater than 900° C. to 1100° C., and whose difference from a maximum achieving temperature during the pressure sintering is within 250° C.

Abstract: Provided are: a method for manufacturing a sintered body as a base of a sintered magnet and a method for manufacturing a permanent magnet. Specifically, a magnet raw material is pulverized into magnet powder, the magnet powder pulverized and a binder are mixed, thereby to form a compound. The, a formed body, obtained by forming the compound formed, is sintered by heating up the same to a firing temperature in a pressed state at a predetermined heat-up rate, and by keeping the same at the firing temperature. In the sintering step, the pressure value for pressing the formed body is set to: less than 3 MPa from the start of heating up of the formed body to a predetermined timing during heating up of the formed body; and 3 MPa or more after the timing.

Abstract: Provided are a rare-earth permanent magnet whose magnet density after sintering is very high and a method for manufacturing a rare-earth permanent magnet. Thus, a magnet raw material is milled into magnet powder, and then, a compound 12 is formed by mixing the magnet powder thus milled with a binder. Next, the compound 12 thus formed is subjected to a hot-melt molding onto a supporting substrate 13 so as to form a green sheet 14 molded to a sheet-like shape. Thereafter, while the green sheet 14 thus molded is softened by heating, magnetic field orientation is carried out by applying a magnetic field to the green sheet 14 thus heated; and further, the green sheet 14 having been subjected to the magnetic field orientation is calcined by a vacuum sintering, which is further followed by a pressure sintering to produce a permanent magnet 1.

Abstract: The present invention provides a permanent magnet unit in which insulating layers are located at positions where an eddy current can be reduced most effectively. The permanent magnet unit includes at least one insulating layer, and a plurality of permanent magnet pieces located adjacent to each other with the at least one insulating layer in between. The at least one insulating layer is located at positions defined based on a magnitude of an eddy current flowing inside a permanent magnet, corresponding to a change in a magnetic field of the permanent magnet into which a plurality of the permanent magnet pieces are integrally formed without the at least one insulating layer.

Abstract: Provided is a heretofore non-existing, novel rare-earth sintered magnet having both of an extremely low carbon content and an extremely small average particle size of magnet material particles. The sintered body for forming a rare-earth magnet comprises a large number of magnet material particles sintered together, wherein each of the magnet material particles contains a rare-earth substance and has an easy magnetization axis. This sintered body for forming a rare-earth magnet has a carbon content of 500 ppm or less, and the magnet material particles have an average particle size of 2 ?m or less.

Abstract: There are provided a rare-earth permanent magnet, and a method for manufacturing a rare-earth permanent magnet and a system for manufacturing a rare-earth permanent magnet, capable of achieving improved shape uniformity. Magnet material is milled into magnet powder, and the milled magnet powder is formed into a formed body 40. The formed body 40 is calcined and then sintered using a spark plasma sintering apparatus 45, so that a permanent magnet 1 is manufactured. A die unit 46 included in the spark plasma sintering apparatus 45 that performs spark plasma sintering at least includes in one direction an inflow hole 50 configured to receive inflow of part of the pressurized formed body.

Abstract: There are provided a rare-earth permanent magnet and a manufacturing method thereof capable of preventing deterioration of magnet properties. In the method, magnet material is milled into magnet powder. Next, a mixture is prepared by mixing the magnet powder and a binder made of long-chain hydrocarbon and/or of a polymer or a copolymer consisting of monomers having no oxygen atoms. Next, the mixture is formed into a sheet-like shape so as to obtain a green sheet. After that, the green sheet is held for a predetermined length of time at binder decomposition temperature in a non-oxidizing atmosphere so as to remove the binder by causing depolymerization reaction or the like to the binder, which turns into monomer. The green sheet from which the binder has been removed is sintered by raising temperature up to sintering temperature. Thereby a permanent magnet 1 is obtained.

Abstract: There are provided a rare-earth permanent magnet and a manufacturing method thereof capable of preventing deterioration of magnet properties. In the method, magnet material is milled into magnet powder. Next, a mixture is prepared by mixing the magnet powder and a binder made of long-chain hydrocarbon and/or of a polymer or a copolymer consisting of monomers having no oxygen atoms. Next, the mixture is formed into a sheet-like shape so as to obtain a green sheet. After that, the green sheet is held for a predetermined length of time at binder decomposition temperature in a non-oxidizing atmosphere so as to remove the binder by causing depolymerization reaction or the like to the binder, which turns into monomer. The green sheet from which the binder has been removed is sintered by raising temperature up to sintering temperature. Thereby a permanent magnet 1 is obtained.

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: 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: Provided are: a permanent magnet wherein the magnetic field orientation process can be made simple and a degree of orientation thereof can be improved; a method for manufacturing a permanent magnet, an SPM motor using a permanent magnet, and a method for manufacturing an SPM motor. Raw material magnet is milled to magnet powder, and the magnet powder is mixed with a binder to form a compound. Then, the compound is molded by hot-melt molding to a green sheet in a shape of a sheet onto a supporting substrate. Thereafter, a magnetic field is applied to the green sheet thus molded to carry out magnetic field orientation. Further, with fixing plural green sheets after the magnetic field orientation by lamination under a deformed state thereof, the plural green sheets thus laminated are cut for shaping to a prescribed shape, which is followed by sintering to produce a permanent magnet.

Abstract: Provided are a rare-earth permanent magnet whose magnet density after sintering is very high and a method for manufacturing a rare-earth permanent magnet. Thus, a magnet raw material is milled into magnet powder, and then, a compound 12 is formed by mixing the magnet powder thus milled with a binder. Next, the compound 12 thus formed is subjected to a hot-melt molding onto a supporting substrate 13 so as to form a green sheet 14 molded to a sheet-like shape. Thereafter, while the green sheet 14 thus molded is softened by heating, magnetic field orientation is carried out by applying a magnetic field to the green sheet 14 thus heated; and further, the green sheet 14 having been subjected to the magnetic field orientation is calcined by a vacuum sintering, which is further followed by a pressure sintering to produce a permanent magnet 1.

Abstract: Provided are: a ring magnet for an SPM motor with which high output power, high efficiency, and low torque ripple of the SPM motor can be realized; a method for manufacturing a ring magnet for an SPM motor; an SPM motor using a ring magnet for an SPM motor; and a method for manufacturing an SPM motor. Raw material magnet is milled to magnet powder, and the magnet powder is molded to a shape of a sheet thereby forming a green sheet. Then, a magnetic field is applied to the green sheet to perform magnetic field orientation. Further, with fixing plural green sheets after the magnetic field orientation by lamination under deformed state thereof, the plural laminated green sheets are cut to a fan-like shape, which is then followed by connecting with each other to form a ring shape and further followed by sintering to produce a permanent magnet.

Abstract: Provided are a rare earth permanent magnet whose permanent magnetic properties are improved by making density of the magnet very high and a method for manufacturing a rare earth permanent magnet. Thus, magnet raw material is milled into magnet powder, and then a compound is formed by mixing the magnet powder thus milled with a binder. Next, the compound thus formed is subjected to hot-melt molding onto a supporting substrate so as to form a green sheet molded to a sheet-like shape. Thereafter, while the green sheet thus molded is softened by heating, magnetic field orientation is carried out by applying a magnetic field to the green sheet thus heated; and further, the green sheet having been subjected to the magnetic field orientation is calcined in non-oxidizing atmosphere, and then, sintering thereof is carried out at a sintering temperature to produce a permanent magnet having density of 95% or more.

Abstract: There are provided a rare-earth permanent magnet and a manufacturing method thereof capable of preventing deterioration of magnet properties. In the method, magnet material is milled into magnet powder. Next, a mixture is prepared by mixing the magnet powder and a binder made of long-chain hydrocarbon and/or of a polymer or a copolymer consisting of monomers having no oxygen atoms. Next, the mixture is formed into a sheet-like shape so as to obtain a green sheet. After that, the green sheet is held for a predetermined length of time at binder decomposition temperature in a non-oxidizing atmosphere so as to remove the binder by causing depolymerization reaction or the like to the binder, which turns into monomer. The green sheet from which the binder has been removed is sintered by raising temperature up to sintering temperature. Thereby a permanent magnet 1 is obtained.

Abstract: There are provided a rare-earth permanent magnet and a manufacturing method thereof capable of preventing deterioration of magnet properties. In the method, magnet material is milled into magnet powder. Next, a mixture is prepared by mixing the magnet powder and a binder made of long-chain hydrocarbon and/or of a polymer or a copolymer consisting of monomers having no oxygen atoms. Next, the mixture is formed into a sheet-like shape so as to obtain a green sheet. After that, the green sheet is held for a predetermined length of time at binder decomposition temperature in a non-oxidizing atmosphere so as to remove the binder by causing depolymerization reaction or the like to the binder, which turns into monomer. The green sheet from which the binder has been removed is sintered by raising temperature up to sintering temperature. Thereby a permanent magnet 1 is obtained.