Abstract: To provide a rare earth magnet ensuring excellent magnetic anisotropy while reducing the amount of Nd, etc., and a manufacturing method thereof. A rare earth magnet comprising a crystal grain having an overall composition of (R2(1-x)R1x)yFe100-y-w-z-vCowBzTMv (wherein R2 is at least one of Nd, Pr, Dy and Tb, R1 is an alloy of at least one or two or more of Ce, La, Gd, Y and Sc, TM is at least one of Ga, Al, Cu, Au, Ag, Zn, In and Mn, 0<x<1, y=12 to 20, z=5.6 to 6.5, w=0 to 8, and v=0 to 2), wherein the average grain size of the crystal grain is 1,000 nm or less, the crystal grain consists of a core and an outer shell, the core has a composition of R1 that is richer than R2, and the outer shell has a composition of R2 that is richer than R1.

Abstract: To provide a rare earth magnet in which particles of SmFeN powder are bound using a Zn powder, wherein generation of a knick at a magnetic field of around 0 is prevented and high residual magnetic flux density Br is thereby achieved, and a production method thereof. A rare earth magnet including a main phase containing Sm, Fe, and N, at least a part of the main phase having a Th2Zn17-type or Th2Ni17-type crystal structure, a sub-phase containing Zn and Fe and being present around the main phase, and an intermediate phase containing Sm, Fe and N as well as Zn and being present between the main phase and the sub-phase, wherein the average Fe content in the sub-phase is 33 at % or less relative to the whole sub-phase.

Abstract: To provide a rare earth magnet in which particles of SmFeN powder are bound using a Zn alloy powder, wherein generation of a knick at a magnetic field of around 0 is prevented, and a production method thereof. A rare earth magnet including a main phase containing Sm, Fe, and N, at least a part of the main phase having a Th2Zn17-type or Th2Ni17-type crystal structure, a sub-phase containing at least either Si or Sm, and Zn and Fe and being present around the main phase, and an intermediate phase containing Sm, Fe and N as well as Zn and being present between the main phase and the sub-phase, wherein the average Fe content in the sub-phase is 33 at % or less relative to the whole sub-phase, and the average total content of Si and Sm in the sub-phase is from 1.4 to 4.5 at % relative to the whole subs-phase.

Abstract: To provide a motor control method ensuring that dragging loss at the time of high rotation can be reduced. A motor control method, wherein a composite permanent magnet has a core part and a shell part, the Curie temperature of one of the core part and the shell part is Tc1 K, and the Curie temperature of another is Tc2 K, and wherein when the magnitude of the reluctance torque is equal to or greater than the magnitude of the magnet torque, the temperature of the composite permanent magnet is set at Ts K that is (Tc1?100) K or higher and lower than Tc2 K and when the magnitude of the reluctance torque is less than the magnitude of the magnetic torque, the temperature of the composite permanent magnet is set at lower than the temperature Ts K or Tc1 K, whichever is lower.

Abstract: To provide a rare earth magnet ensuring excellent magnetic anisotropy while reducing the amount of Nd, etc., and a manufacturing method thereof. A rare earth magnet comprising a crystal grain having an overall composition of (R2(1-x)R1x)yFe100-y-w-z-vCowBzTMv (wherein R2 is at least one of Nd, Pr, Dy and Tb, R1 is an alloy of at least one or two or more of Ce, La, Gd, Y and Sc, TM is at least one of Ga, Al, Cu, Au, Ag, Zn, In and Mn, 0<x<1, y=12 to 20, z=5.6 to 6.5, w=0 to 8, and v=0 to 2), wherein the average grain size of the crystal grain is 1,000 nm or less, the crystal grain consists of a core and an outer shell, the core has a composition of R1 that is richer than R2, and the outer shell has a composition of R2 that is richer than R1.

Abstract: To provide a rare earth magnet ensuring excellent magnetic anisotropy while reducing the amount of Nd, etc., and a manufacturing method thereof. A rare earth magnet comprising a crystal grain having an overall composition of (R2(1-x)R1x)yFe100-y-w-z-vCowBzTMv (wherein R2 is at least one of Nd, Pr, Dy and Tb, R1 is an alloy of at least one or two or more of Ce, La, Gd, Y and Sc, TM is at least one of Ga, Al, Cu, Au, Ag, Zn, In and Mn, 0<x<1, y=12 to 20, z=5.6 to 6.5, w=0 to 8, and v=0 to 2), wherein the average grain size of the crystal grain is 1,000 nm or less, the crystal grain consists of a core and an outer shell, the core has a composition of R1 that is richer than R2, and the outer shell has a composition of R2 that is richer than R1.

Abstract: A method for producing a raw material powder of a permanent magnet, includes: preparing a material powder of a permanent magnet, measuring magnetic characteristics of the material powder, and judging the quality of the material powder as the raw material powder based on a preliminarily determined relation between magnetic characteristics and the structure of the material powder. A method for producing a permanent magnet includes integrating material powders judged as good in the step of judging the quality as raw material powders by the method for producing a raw material powder of a permanent magnet. A method for inspecting a permanent magnet material powder includes transmitting a magnetic field to a material powder of a permanent magnet, receiving the magnetic field from the material powder, and measuring a magnetic field difference between the transmitted magnetic field and the received magnetic field as magnetic characteristics of the material powder.

Abstract: To provide a rare earth magnet ensuring excellent magnetic anisotropy while reducing the amount of Nd, etc., and a manufacturing method thereof. A rare earth magnet comprising a crystal grain having an overall composition of (R2(1-x)R1x)yFe100-y-w-z-vCowBzTMv (wherein R2 is at least one of Nd, Pr, Dy and Tb, R1 is an alloy of at least one or two or more of Ce, La, Gd, Y and Sc, TM is at least one of Ga, Al, Cu, Au, Ag, Zn, In and Mn, 0<x<1, y=12 to 20, z=5.6 to 6.5, w=0 to 8, and v=0 to 2), wherein the average grain size of the crystal grain is 1,000 nm or less, the crystal grain consists of a core and an outer shell, the core has a composition of R1 that is richer than R2, and the outer shell has a composition of R2 that is richer than R1.

Abstract: A method includes: manufacturing a sintered compact represented by (Rl)x(Rh)yTzBsMt and has a grain boundary phase; manufacturing a rare earth magnet precursor from the sintered compact; and performing a heat treatment on the rare earth magnet precursor at 450° C. to 700° C. to diffuse and to infiltrate a melt of a modified alloy containing a light rare earth element and either a transition metal element, Al, In, Zn, or Ga into the grain boundary phase. Rl represents a light rare earth element. Rh represents Dy or Tb. T represents a transition metal containing at least one of Fe, Ni, and Co. B represents boron. M represents at Ga, Al, or Cu. x, y, z, s, and t represent mass % of Rl, Rh, T, B, and M. Following expressions are established: 27?x?44, 0?y?10, z=100?x?y?s?t, 0.75?s?3.4, 0?t?3. An infiltration amount of the modified alloy is 0 mass % to 5 mass %.

Abstract: A manufacturing method includes: manufacturing a sintered compact having a composition of (Rl)x(Rh)yTzBsMt; manufacturing a precursor by performing hot deformation processing on the sintered compact; and manufacturing a rare earth magnet by performing an aging treatment on the precursor in a temperature range of 450° C. to 700° C. In this method, a main phase thereof is formed of a (RlRh)2T14B phase. A content of a (RlRh)1.1T4B4 phase in a grain boundary phase thereof is more than 0 mass % and 50 mass % or less. Rl represents a light rare earth element. Rh represents a heavy rare earth element. T represents a transition metal. M represents at least one of Ga, Al, Cu, and Co. x, y, z, s, and t are percentages by mass of Rl, Rh, T, B, and M. x, y, z, s, and t are expressed by the following expressions: 27?x?44, 0?y?10, z=100?x?y?s?t, 0.75?s?3.4, 0?t?3.

Abstract: Provided is a rare-earth magnet containing no heavy rare-earth metals such as Dy or Tb in a grain boundary phase, has a modifying alloy for increasing coercivity (in particular, coercivity under a high-temperature atmosphere) infiltrated thereinto at lower temperature than in the conventional rare-earth magnets, has high coercivity, and has relatively high magnetizability, and a production method therefor. The rare-earth magnet RM includes a RE-Fe—B-based main phase MP with a nanocrystalline structure (where RE is at least one of Nd or Pr) and a grain boundary phase BP around the main phase, the grain boundary phase containing a RE-X alloy (where X is a metallic element other than heavy rare-earth elements). Crystal grains of the main phase MP are oriented along the anisotropy axis, and each crystal grain of the main phase, when viewed from a direction perpendicular to the anisotropy axis, has a plane that is quadrilateral in shape or has a close shape thereto.

Abstract: A method of manufacturing a rare earth magnet includes: preparing a powder by preparing a rapidly-solidified ribbon by liquid solidification, and by crushing the rapidly-solidified ribbon; manufacturing a sintered compact by press-forming the powder; and manufacturing a rare earth magnet by performing hot deformation processing on the sintered compact to impart anisotropy to the sintered compact. In this method, the rapidly-solidified ribbon is a plurality of fine crystal grains. The powder includes a RE-Fe—B main phase and a grain boundary phase of a RE-X alloy present around the main phase. RE represents at least one of Nd and Pr. X represents a metal element. A nitrogen content in the powder is adjusted to be at least 1,000 ppm and less than 3,000 ppm by performing at least one of the preparation of the powder and the manufacturing of the sintered compact in a nitrogen atmosphere.

Abstract: To provide a rare earth magnet having excellent coercive force and a production method thereof. A rare earth magnet, wherein the rare earth magnet comprises a magnetic phase containing Sm, Fe, and N, a Zn phase present around the magnetic phase, and an intermediate phase present between the magnetic phase and the Zn phase, wherein the intermediate phase contains Zn and the oxygen content of the intermediate phase is higher than the oxygen content of the Zn phase; and a method for producing a rare earth magnet, including mixing a magnetic raw material powder having an oxygen content of 1.0 mass % or less and an improving agent powder containing metallic Zn and/or a Zn alloy, and heat-treating the mixed powder.

Abstract: A method for producing a rare earth magnet, including preparing a melt of a first alloy having a composition represented by (R1vR2wR3x)yTzBsM1t (wherein R1 is a light rare earth element, R2 is an intermediate rare earth element, R3 is a heavy rare earth element, T is an iron group element, and M1 is an impurity element, etc.), cooling the melt of the first alloy at a rate of from 100 to 102 K/sec to obtain a first alloy ingot, pulverizing the first alloy ingot to obtain a first alloy powder having a particle diameter of 1 to 20 ?m, preparing a melt of a second alloy having a composition represented by (R4pR5q)100-uM2u (wherein R4 is a light rare earth element, R5 is an intermediate or heavy rare earth element, M2 is an alloy element, etc.), and putting the first alloy powder into contact with the melt of the second alloy.

Abstract: The present invention is a method capable of producing a rare-earth magnet with excellent magnetization and coercivity. The method includes producing a sintered body including a main phase and grain boundary phase and represented by (R11-xR2x)aTMbBcMd (where R1 represents one or more rare-earth elements including Y, R2 represents a rare-earth element different than R1, TM represents transition metal including at least one of Fe, Ni, or Co, B represents boron, M represents at least one of Ti, Ga, Zn, Si, Al, etc., 0.01?x?1, 12?a?20, b=100?a?c?d, 5?c?20, and 0?d?3 (all at %)); applying hot deformation processing to the sintered body to produce a precursor of the magnet; and diffusing/infiltrating melt of a R3-M modifying alloy (rare-earth element where R3 includes R1 and R2) into the grain boundary phase of the precursor.

Abstract: A rare earth magnet comprising a main phase, a grain boundary phase present around the main phase, and an intermediate phase sandwiched between the main phase and the grain boundary phase, and having a total composition of the rare earth magnet represented by the formula: CepR1qT(100-p-q-r-s)BrM1s.(R21-xM2x)t R1 and R2 are a rare earth element except for Ce, T is one or more members selected from Fe, Ni, and Co, M1 is a minor element, and M2 is an alloy element that makes, the melting point of R21-xM2x to be lower than the melting point of R2 the concentration of Ce is higher in the main phase than in the intermediate phase, and the concentration of R2 is higher in the intermediate phase than in the main phase, and a production method thereof.

Abstract: To provide an R—Fe—B-based rare earth magnet where R is mainly Ce, ensuring that even when a rare earth element R1 except for Ce is very small in amount or is not present, the coercive force can be enhanced. A rare earth magnet wherein the rare earth magnet has a total composition represented by the formula: CepR1qT(100-p-q-r-s)BrM1s (wherein R1 is a rare earth element except for Ce, T is one or more members selected from Fe, Ni and Co, M1 is one or more members selected from Ti, Ga, Zn, Si, Al, Nb, Zr, Mn, V, W, Ta, Ge, Cu, Cr, Hf, Mo, P, C, Mg, Hg, Ag, and Au, and an unavoidable impurity, and p, q, r, and s are 11.80?p?12.90, 0?q?3.00, 5.00?r?20.00, and 0?s?3.00), and wherein the rear earth magnet comprises a magnetic phase and a (Ce,R1)-rich phase present around the magnetic phase.

Abstract: A rare earth magnet includes a main phase, a grain boundary phase present around the main phase and an intermediate phase interposed between the main phase and the grain boundary phase, and has an overall composition that is represented by the formula ((Ce(1-x)Lax)(1-y)R1y)pT(100-p-q-r)BqM1r.(R21-zM2z)s (where, R1 and R2 are rare earth elements other than Ce and La, T is at least one selected from among Fe, Ni, and Co, M1 is an element having a small amount that does not influence magnetic characteristics, and M2 is an alloy element for which a melting point of R21-zM2z is lower than a melting point of R2). A total concentration of Ce and La is higher in the main phase than in the intermediate phase, and a concentration of R2 is higher in the intermediate phase than in the main phase.

Abstract: A method for manufacturing a rare-earth magnet, through hot deformation processing, having a high degree of orientation at the entire area thereof and high remanence, without increasing processing cost including a step of press-forming powder as a rare-earth magnetic material to form a compact S; and a step of performing hot deformation processing to the compact S, thus manufacturing the rare-earth magnet C. The hot deformation processing includes two steps of extruding and upsetting. The extruding is to place a compact S in a die Da, and apply pressure to the compact S? in a heated state with an extrusion punch PD so as to reduce the thickness for extrusion to prepare the rare-earth magnet intermediary body S? having a sheet form, and the upsetting is to apply pressure to the rare-earth magnet intermediary body S? in the thickness direction to reduce the thickness, thus manufacturing the rare-earth magnet C.

Abstract: Provided is a method for manufacturing a rare-earth magnet capable of manufacturing a rare-earth magnet with high degree of orientation by sufficient plastic deformation while suppressing cracks at the side faces of a compact that is plastic-deformed during the hot deformation processing. The method includes a step of preparing a compact S, preparing a plastic processing mold including a die D in which a cavity Ca is provided, and punches P that are slidable in the cavity Ca, the cavity Ca having a cross section that is larger in cross-sectional dimensions than a cross section of the compact S that is orthogonal to a pressing direction by the punches P; and a step of placing the compact S in the cavity Ca and performing hot deformation processing, thus manufacturing an orientational magnet C.