Abstract: An object of the present invention is to provide an R—Fe—B based sintered magnet having on a surface thereof a chemical conversion film with higher corrosion resistance than a conventional chemical conversion film such as a phosphate film, and a method for producing the same. The corrosion-resistant magnet of the present invention as a means for achieving the object is characterized by comprising a chemical conversion film containing at least Zr, Nd, fluorine, and oxygen as constituent elements and not containing phosphorus directly on a surface of an R—Fe—B based sintered magnet, wherein R is a rare-earth element including at least Nd.

Abstract: An R-T-B—C rare earth sintered magnet (R?Ce, Pr, Nd, Tb, or Dy; T=Fe) is obtained by mixing an R-T-B—C magnet matrix alloy with an R fluoride and an R-rich R-T-B—C sintering aid alloy, followed by pulverization, compaction and sintering. The sintered structure consists of an R2T14B type crystal primary phase and a grain boundary phase. The grain boundary phase consists essentially of 40-98 vol % of R—O1-x—F1+2x and/or R—Fy, 1-50 vol % of R—O, R—O—C or R—C compound phase, 0.05-10 vol % of R-T phase, 0.05-20 vol % of B-rich phase or M-B2 phase (M=Ti, V, Cr, Zr, Nb, Mo, Hf, Ta or W), and the balance of an R-rich phase.

Abstract: A nanocomposite magnet according to the present invention has a composition represented by the general formula: RxQyMz(Fe1-mTm)bal, where R is at least one rare-earth element, Q is at least one element selected from the group consisting of B and C, M is at least one metal element that is selected from the group consisting of Al, Si, Ti, V, Cr, Mn, Cu, Zn, Ga, Zr, Nb, Mo, Ag, Hf, Ta, W, Pt, Au and Pb and that always includes Ti, and T is at least one element selected from the group consisting of Co and Ni. The mole fractions x, y, z and m satisfy the inequalities of 6 at %?x<10 at %, 10 at %?y?17 at %, 0.5 at %?z?6 at % and 0?m?0.5, respectively. The nanocomposite magnet includes a hard magnetic phase and a soft magnetic phase that are magnetically coupled together. The hard magnetic phase is made of an R2Fe14B-type compound, and the soft magnetic phase includes an ?-Fe phase and a crystalline phase with a Curie temperature of 610° C. to 700° C. (? phase) as its main phases.

Abstract: A rare earth permanent magnet is prepared by disposing a powdered metal alloy containing at least 70 vol % of an intermetallic compound phase on a sintered body of R—Fe—B system, and heating the sintered body having the powder disposed on its surface below the sintering temperature of the sintered body in vacuum or in an inert gas for diffusion treatment. The advantages include efficient productivity, excellent magnetic performance, a minimal or zero amount of Tb or Dy used, an increased coercive force, and a minimized decline of remanence.

Abstract: A magnet comprising grains of a ferromagnetic material whose main component is iron and a fluorine compound layer or an oxy-fluorine compound layer of fluoride compound particles of alkali metals, alkaline earth metals and rare earth elements, present on the surface of the ferromagnetic material grains, wherein an amount of iron atoms in the fluorine compound particles is 1 to 50 atomic %.

Abstract: A permanent magnet material is prepared by covering an anisotropic sintered magnet body of formula: R1x(Fe1-yCoy)100-x-z-aBzMa wherein R1 is a rare earth element, M is Al, Cu or the like, with a powder comprising an oxide of R2, a fluoride of R3 or an oxyfluoride of R4 wherein R2, R3, and R4 are rare earth elements, and having an average particle size up to 100 ?m, heat treating the powder-covered magnet body in a hydrogen gas-containing atmosphere for inducing disproportionation reaction on R12Fe14B compound, and continuing heat treatment at a reduced hydrogen gas partial pressure for inducing recombination reaction to said compound, thereby finely dividing said compound phase to a crystal grain size up to 1 ?m, and for effecting absorption treatment, thereby causing R2, R3 or R4 to be absorbed in the magnet body.

Abstract: A method for producing a rare-earth alloy based binderless magnet according to the present invention includes the steps of: (A) providing a rapidly solidified rare-earth alloy magnetic powder; and (B) compressing and compacting the rapidly solidified rare-earth alloy magnetic powder by a cold process without using a resin binder, thereby obtaining a compressed compact, 70 vol % to 95 vol % of which is the rapidly solidified rare-earth alloy magnetic powder.

Abstract: A magnet comprising magnetic powder containing at least one rare earth metal element, and an oxide binder for binding the magnetic powder, wherein an inter-face distance of the binder determined by diffraction analysis is 0.25 to 2.94 nm. The disclosure also discloses a method of manufacturing a magnet comprising; compacting magnetic powder containing at least one rare earth element under pressure in a mold; impregnating the compacted magnetic powder molding with a precursor solution of an oxide material; and heat-treating the compacted magnetic molding impregnated with the precursor thereby to impart an inter-face distance determined by diffraction analysis to the binder in the compacted molding. The distance is 0.25 to 2.94 nm.

Abstract: A permanent magnet material is prepared by machining an anisotropic sintered magnet body having the compositional formula: Rx(Fe1-yCoy)100-x-z-aBzMa wherein R is Sc, Y or a rare earth element, M is Al, Cu or the like, to a specific surface area of at least 6 mm?1, heat treating in a hydrogen gas-containing atmosphere at 600-1,100° C. for inducing disproportionation reaction on the R2Fe14B compound, and continuing heat treatment at a reduced hydrogen gas partial pressure and 600-1,100° C. for inducing recombination reaction to the R2Fe14B compound, thereby finely dividing the R2Fe14B compound phase to a crystal grain size ?1 ?m.

Abstract: The object of the present invention is to provide a rare earth magnet which enables to achieve a good balance between high coercive force and high residual magnetic flux density, and its manufacturing method. The present invention provides a rare earth magnet in which a layered grain boundary phase is formed on a surface or a portion of a grain boundary of Nd2Fe14B which is a main phase of an R—Fe—B (R is a rare-earth element) based magnet, and wherein the grain boundary phase contains a fluoride compound, and wherein a thickness of the fluoride compound is 10 ?m or less, or a thickness of the fluoride compound is from 0.1 ?m to 10 ?m, and wherein the coverage of the fluoride compound over a main phase particle is 50% or more on average.

Abstract: The object of the present invention is to both reduce costs and improve magnetic characteristics of rare-earth bond magnets in which magnetic material is bound with a binding agent. In order to achieve this object, magnetic characteristics of a magnet are improved by performing cold forming on rare-earth magnetic powder by itself with no resin added. Then, in order to provide strength for the magnet, a low-viscosity SiO2 precursor is infiltrated and thermoset in the magnet shaped body. As a result, it is possible to obtain a rare-earth bond magnet in which magnetic characteristics are improved and costs are reduced.

Abstract: A method of making a magnetically anisotropic magnet powder according to the present invention includes the steps of preparing a master alloy by cooling a rare-earth-iron-boron based molten alloy and subjecting the master alloy to an HDDR process. The step of preparing the master alloy includes the step of forming a solidified alloy layer, including a plurality of R2Fe14B-type crystals (where R is at least one element selected from the group consisting of the rare-earth elements and yttrium) in which rare-earth-rich phases are dispersed, by cooling the molten alloy through contact with a cooling member.

Abstract: A rare earth permanent magnet is prepared by providing a sintered magnet body consisting of 12-17 at % of rare earth, 3-15 at % of B, 0.01-11 at % of metal element, 0.1-4 at % of O, 0.05-3 at % of C, 0.01-1 at % of N, and the balance of Fe, disposing on a surface of the magnet body a powder comprising an oxide, fluoride and/or oxyfluoride of another rare earth, and heat treating the powder-covered magnet body at a temperature below the sintering temperature in vacuum or in an inert gas, for causing the other rare earth to be absorbed in the magnet body.

Abstract: A sintered magnet and a rotating machine equipped therewith are disclosed, which include: crystal grains of a ferromagnetic material consisting mainly of iron, and a fluoride compound or an oxyfluoride compound, containing at least one element selected from the group consisting of an alkali metal element, an alkaline earth metal element, and a rare earth element, the fluoride compound or the oxyfluoride compound being formed inside some of the crystal grains or in a part of a grain boundary part. The oxyfluoride compound or the fluoride compound contains carbon, and a grain boundary width of the ferromagnetic material is smaller than a grain boundary width of the ferromagnetic material in which the fluoride compound or the oxyfluoride compound is formed.

Abstract: The object of the present invention is to provide a rare earth magnet which enables to achieve a good balance between high coercive force and high residual magnetic flux density, and its manufacturing method. The present invention provides a rare earth magnet in which a layered grain boundary phase is formed on a surface or a potion of a grain boundary of Nd2Fe14B which is a main phase of an R—Fe—B (R is a rare-earth element) based magnet, and wherein the grain boundary phase contains a fluoride compound, and wherein a thickness of the fluoride compound is 10 ?m or less, or a thickness of the fluoride compound is from 0.1 ?m to 10 ?m, and wherein the coverage of the fluoride compound over a main phase particle is 50% or more on average.

Abstract: In a rare earth magnet, an added heavy rare earth element RH such as Dy is effectively used without any waste, so as to effectively improve the coercive force. First, a molten alloy of a material alloy for an R-T-Q rare earth magnet (R is a rare earth element, T is a transition metal element, and Q is at least one element selected from the group consisting of B, C, N, Al, Si, and P), the rare earth element R containing at least one kind of element RL selected from the group consisting of Nd and Pr and at least one kind of element RH selected from the group consisting of Dy Tb, and Ho is prepared. The molten alloy is quenched, so as to produce a solidified alloy. Thereafter, a thermal treatment in which the rapidly solidified alloy is held in a temperature range of 400° C. or higher and lower than 800° C. for a period of not shorter than 5 minutes nor longer than 12 hours is performed.

Abstract: A rare earth magnet is prepared by disposing a R1-T-B sintered body comprising a R12T14B compound as a major phase in contact with an R2-M alloy powder and effecting heat treatment for causing R2 element to diffuse into the sintered body. The alloy powder is obtained by quenching a melt containing R2 and M. R1 and R2 are rare earth elements, T is Fe and/or Co, M is selected from B, C, P, Al, Si, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Zr, Nb, Mo, Ag, In, Sn, Sb, Hf, Ta, W, Pt, Au, Pb, and Bi.

Abstract: An R-T-B type alloy (wherein R is at least one member selected from rare earth elements, T is a transition metal including Fe, and B includes boron) which is a raw material for use in a rare earth-based permanent magnet, wherein the volume percentage of the region containing an R2T17 phase having an average grain diameter of 3 ?m or less in the short axis direction is from 0.5 to 10%.

Abstract: The iron-based rare-earth nanocomposite magnet of the present invention has a composition T100?x?y?z?nQxRyTizMn, where T is Fe or a transition metal element in which Fe is partially replaced by Co and/or Ni; Q is B and/or C; R is at least one rare-earth element including substantially no La or Ce; and M is at least one metal element selected from Al, Si, V, Cr, Mn, Cu, Zn, Ga, Zr, Nb, Mo, Ag, Hf, Ta, W, Pt, Au and Pb. x, y, z and n satisfy 5?x?10 at %, 7?y?10 at %, 0.1?z?5 at % and 0?n?10 at %, respectively. The magnet includes R2Fe14B-type compound phases and ? —Fe phases forming a magnetically coupled nanocomposite magnet structure. The R2Fe14B-type compound phases have an average crystal grain size of 30 nm to 300 nm and the ? —Fe phases have an average crystal grain size of 1 nm to 20 nm. The magnet has magnetic properties including a coercivity of at least 400 kA/m and a remanence of at least 0.9 T.

Abstract: An alloy is used for production of magnetic refrigeration material particles. The alloy contains La in a range of 4 to 15 atomic %, Fe in a range of 60 to 93 atomic %, Si in a range of 3.5 to 23.5 atomic % and at lease one element M selected from B and Ti in a range of 0.5 to 1.5 atomic %. The alloy includes a main phase containing Fe as a main component element and Si, and a subphase containing La as a main component element and Si. The main phase has a bcc crystal structure and an average grain diameter of 20 ?m or less.

Abstract: The present invention is aimed at providing a method for producing an NdFeB sintered magnet having a higher coercivity and higher squareness of the magnetization curve than ever before. A method for producing an NdFeB sintered magnet according to the present invention includes the steps of forming a layer containing Dy and/or Tb on the surface of an NdFeB sintered magnet base material and then performing a grain boundary diffusion process for diffusing Dy and/or Tb from the aforementioned layer through the crystal grain boundaries of the magnet base material into the magnet base material by heating the magnet base material to a temperature equal to or lower than the sintering temperature thereof, and this method is characterized in that a) the content of a rare earth in a metallic state in the magnet base material is equal to or higher than 12.

Abstract: An anisotropic rare-earth bonded magnet having a network boundary phase is provided by imparting melt fluidity accompanied by a slip to a composite granule and compressing and molding the composite granule in a magnetic field together with extensible polymer molecules and a chemical contact. In the bonded magnet, the maximum energy product is 147 kJ/m3 in the thickness of 1 mm, or 127 kJ/m3 in the thickness of 300 ?m. This bonded magnet contributes to increase in output and decrease in size and weight of a permanent-magnet motor.

Abstract: In known methods, an improvement of the coercive force is realized by allowing the Dy metal or the like to present selectively in crystal grain boundary portions of a sintered magnet. However, since these are based on a physical film formation method, e.g., sputtering, through the use of a vacuum vessel, there is a mass productivity problem when a large number of magnets are treated. Furthermore, there is a magnet cost problem from the viewpoint that, for example, an expensive, high-purity Dy metal or the like must be used as a raw material for film formation. The method for modifying grain boundaries of a Nd—Fe—B base magnet includes the step of allowing an M metal component to diffuse and penetrate from a surface of a Nd—Fe—B base sintered magnet body having a Nd-rich crystal grain boundary phase surrounding principal Nd2Fe14B crystals to the grain boundary phase through a reduction treatment of a fluoride, an oxide, or a chloride of an M metal element (where M is Pr, Dy, Tb, or Ho).

Abstract: An objective of the present invention is to provide a rare earth metal-based sintered magnet having imparted thereto sufficient corrosion resistance by an oxidative heat treatment, which is resistant even in an environment of fluctuating humidity, while suppressing the deterioration of the magnetic characteristics ascribed to the oxidative heat treatment, and to provide a method for producing the same.

Abstract: A lamellar high resistance layer having resistivity ten times or higher than that of a mother phase containing iron or cobalt is formed and an oxygen content is controlled to 10 to 10000 ppm so that the reliability and residual magnetic flux density are increased.

Abstract: The sintered magnet and the rotating machine equipped with the same are disclosed. The sintered magnet includes crystal grains of a ferromagnetic material consisting mainly of iron, and a fluoride compound or oxyfluoride compound layer containing at least one element selected from an alkali metal element, an alkali earth metal element, and a rare earth element. The layer is formed inside some of the crystal grains or in a part of a grain boundary part. An oxyfluoride compound or fluoride compound layer containing carbon in a stratified form is formed on an outermost surface of the crystal grains. The fluoride compound or oxyfluoride compound layer has a concentration gradient of carbon, contains at least one light rare earth element and at least one heavy rare earth element. The heavy rare earth element has a concentration lower than that of the light rare earth element.

Abstract: An R-T-B based sintered magnet according to the present invention comprises: 12 at % to 15 at % of a rare-earth element R; 5.0 at % to 8.0 at % of boron B; 0.02 at % to 0.2 at % of Mn; and a transition metal T as the balance. The rare-earth element R is at least one element selected from the rare-earth elements, including Y (yttrium), and includes 0.2 at % to 8 at % of Pr. And the transition element T includes Fe as its main element.

Abstract: The invention provides a method for producing alloy flakes for rare earth sintered magnets, which makes uniform the intervals, size, orientation, and shape of the R-rich region and the dendrites of the 2-14-1 phase, which inhibits formation of chill, and which produces flakes that are pulverized into powder of a uniform particle size in the pulverization step in the production of a rare earth sintered magnet, and that are pulverized into powder compactable into a product with a controlled shrink ratio, and alloy flakes for a rare earth sintered magnet obtained by the method, and a rare earth sintered magnet having excellent magnetic properties.

Abstract: A material for anisotropic magnet, comprising, (1) a Pr-T-B—Ga-based composition containing Pr: 12.5 to 15.0 atomic percent, B: 4.5 to 6.5 atomic percent, Ga: 0.1 to 0.7 atomic percent, and the balance of T and inevitable impurities, wherein T is Fe or obtained by substituting Co for a portion of the Fe; and having, (2) a degree of magnetic alignment of 0.92 or more, wherein the degree of magnetic alignment is defined by remanence (Br)/saturation magnetization (Js); and (3) a crystal grain diameter of 1 ?m or less.

Abstract: The present invention provides a technique to improve an adhesion strength between a magnet main body and a protective film. The rare earth sintered magnet of the present invention comprises a magnet main body of a sintered body containing a rare earth element and a protective film formed on the magnet main body, wherein the ratio of a 10-point average surface roughness Rz of the magnet main body on which the protective film is formed to a mean grain size D50 in the magnet main body (Rz/D50 ratio) is kept in a range from 0.20 to 10.00, inclusive. This gives the rare earth sintered magnet which is coated with the protective film having a high adhesion strength of 100 N/m or more and exhibits high corrosion resistance.

Abstract: An R-T-B based sintered magnet according to the present invention has a composition comprising: 12 at % to 15 at % of a rare-earth element R; 5.0 at % to 8.0 at % of boron B; 0.1 at % to at % of Al; 0.02 at % to less than 0.2 at % of Mn; and a transition metal T as the balance. The rare-earth element R is at least one element selected from the rare-earth elements, including Y (yttrium), and includes at least one of Nd and Pr. The transition element T includes Fe as its main element.

Abstract: The invention provides a method for producing alloy flakes for rare earth sintered magnets, which makes uniform the intervals, size, orientation, and shape of the R-rich region and the dendrites of the 2-14-1 phase, which inhibits formation of chill, and which produces flakes that are pulverized into powder of a uniform particle size in the pulverization step in the production of a rare earth sintered magnet, and that are pulverized into powder compactable into a product with a controlled shrink ratio, and alloy flakes for a rare earth sintered magnet obtained by the method, and a rare earth sintered magnet having excellent magnetic properties.

Abstract: By causing at least one of Dy and Tb to be adhered to the surface of an iron-boron-rare earth based sintered magnet of a predetermined shape, and is then to be diffused into grain boundary phase, a permanent magnet can be manufactured at high workability and low cost. An iron-boron-rare earth based sintered magnet is disposed in a processing chamber and is heated to a predetermined temperature. Also, an evaporating material made up of a fluoride containing at least one of Dy and Tb disposed in the same or another processing chamber is evaporated, and the evaporated evaporating material is caused to be adhered to the surface of the sintered magnet. The Dy and/or Tb metal atoms of the adhered evaporating material are diffused into the grain particle phase of the sintered magnet before a thin film made of the evaporated material is formed on the surface of the sintered magnet.

Abstract: There is provided a method of manufacturing a permanent magnet in which Dy and/or Tb adhered to the surface of a sintered magnet containing a lubricant can be efficiently diffused and in which the permanent magnet having high magnetic properties can be manufactured at good productivity. The permanent magnet is manufactured by executing a first step of adhering at least one of Dy and Tb to at least a part of a surface of a sintered magnet made by sintering iron-boron-rare earth based alloy raw meal powder containing a lubricant; and a second step of heat-treating the sintered magnet at a predetermined temperature to thereby disperse at least one of Dy and Tb adhered to the surface of the sintered magnet into grain boundary phase of the sintered magnet. At this time, as the sintered magnet, there is used one manufactured in an average grain size within a range of 4 ?m˜8 ?m.

Abstract: A rare earth magnet powder has a chemical composition which includes R: 5 to 20% (wherein, R represents one or two or more rare earth elements being inclusive of Y but exclusive of Dy and Tb), one or two of Dy and Tb: 0.01 to 10%, and B: 3 to 20%, with the balance comprising Fe and inevitable impurities; and an average particle diameter of 10 to 1,000 ?m, wherein 70% or more of the entire surface of the rare earth magnet powder is covered with a layer being rich in the content of one or two of Dy and Tb and having a thickness of 0.05 to 50 ?m.

Abstract: A method of making a rare-earth alloy granulated powder according to the present invention includes the steps of: preparing a rare-earth alloy powder; generating remanent magnetization in the powder; and granulating the powder by utilizing agglomeration force produced by the remanent magnetization of the powder. Since the agglomeration force produced by the remanent magnetization is utilized, the addition of a granulating agent may be omitted.

Abstract: A radial anisotropic sintered magnet formed into a cylindrical shape includes a portion oriented in directions tilted at an angle of 30° or more from radial directions, the portion being contained in the magnet at a volume ratio in a range of 2% or more and 50% or less, and a portion oriented in radial directions or in directions tilted at an angle less than 30° from radial directions, the portion being the rest of the total volume of the magnet. The radial anisotropic sintered magnet has excellent magnet characteristics without occurrence of cracks in the steps of sintering and cooling for aging, even if the magnet has a shape of a small ratio between an inner diameter and an outer diameter.

Abstract: An R-T-B system rare earth permanent magnet, which comprises main phase grains consisting of R2T14B compounds and a grain boundary phase having a higher amount of R than the above described main phase grains, and which satisfies AVE(X)/Y=0.8 to 1.0; and (X/Y)max/(X/Y)min=2.0 to 13.0, wherein X represents (weight ratio of heavy rare earth elements)/(the weight ratio of all rare earth elements) for a given number of the above described main phase grains Y represents (weight ratio of heavy rare earth elements)/(weight ratio of all rare earth elements) for the sintered body as a whole; AVE(X) represents the mean value of X obtained for the given number of main phase grains; (X/Y)min represents the minimum value of (X/Y) obtained for the given number of main phase grains; and (X/Y)max represents the maximum value of (X/Y) obtained for the given number of main phase grains.

Abstract: A rare earth magnet includes rare earth magnet particles; and amorphous and/or crystalline terbium oxide present at the boundary of the rare earth magnet particles and represented by the formula: TbOn, wherein 1.5<n?2. The rare earth magnet prevents decrease eddy current effectively.

Abstract: The present invention is an alloy lump for R-T-B type sintered magnets, including an R2T14B columnar crystal and an R-rich phase (in which R is at least one rare earth element including Y, T is Fe or Fe with at least one transition metal element except for Fe, and B is boron or boron with carbon), in which in the as-cast state, R-rich phases nearly in the line-like or rod-like shape (the width direction of the line or rod is a short axis direction) are dispersed in the cross section, and the area percentage of the region where R2T14B columnar crystal grains have a length of 500 ?m or more in the long axis direction and a length of 50 ?m or more in the short axis direction is 10% or more of the entire alloy.

Abstract: The iron-based rare-earth nanocomposite magnet of the present invention has a composition T100-x-y-z-nQxRyTizMn, where T is Fe or a transition metal element in which Fe is partially replaced by Co and/or Ni; Q is B and/or C; R is at least one rare-earth element including substantially no La or Ce; and M is at least one metal element selected from Al, Si, V, Cr, Mn, Cu, Zn, Ga, Zr, Nb, Mo, Ag, Hf, Ta, W, Pt, Au and Pb. x, y, z and n satisfy 5?x?10 at %, 7?y?10 at %, 0.1?z?5 at % and 0?n?10 at %, respectively. The magnet includes R2Fe14B-type compound phases and ? —Fe phases forming a magnetically coupled nanocomposite magnet structure. The R2Fe14B-type compound phases have an average crystal grain size of 30 nm to 300 nm and the ? —Fe phases have an average crystal grain size of 1 nm to 20 nm. The magnet has magnetic properties including a coercivity of at least 400 kA/m and a remanence of at least 0.9 T.

Abstract: A method of making a material alloy for an R-T-Q based rare-earth magnet according to the present invention includes the steps of: preparing a melt of an R-T-Q based rare-earth alloy, where R is rare-earth elements, T is a transition metal element, Q is at least one element selected from the group consisting of B, C, N, Al, Si and P, and the rare-earth elements R include at least one element RL selected from the group consisting of Nd, Pr, Y, La, Ce, Pr, Sm, Eu, Gd, Er, Tm, Yb and Lu and at least one element RH selected from the group consisting of Dy, Tb and Ho; cooling the melt of the alloy to a temperature of 700° C. to 1,000° C. as first cooling process, thereby making a solidified alloy; maintaining the solidified alloy at a temperature within the range of 700° C. to 900° C. for 15 seconds to 600 seconds; and cooling the solidified alloy to a temperature of 400° C. or less as a second cooling process.

Abstract: A material for magnetic anisotropic magnet, comprising (1) a Pr-T-B—Ga-based composition containing Pr: 13.0 to 15.0 atomic percent, B: 4.5 to 6.5 atomic percent, Ga: 0.1 to 0.7 atomic percent, and the balance of. T and inevitable impurities, wherein T is obtained by substituting Co for Fe or a portion of Fe, (2) the material for magnetic anisotropic magnet is obtained by rapidly-cooling a molten alloy having the composition, pulverizing the ribbon obtained by the rapid-cooling, cold-forming the alloy powder obtained by the pulverizing, hot-forming the cold-formed body, and performing hot plastic working to the hot-formed body, and (3) the degree of magnetic orientation of the material for magnetic anisotropic magnet, which is defined by remanence (Br)/saturation magnetic flux density (Js), is 0.9 or more.

Abstract: The object of the present invention is to provide a rare earth magnet which enables to achieve a good balance between high coercive force and high residual magnetic flux density, and its manufacturing method. The present invention provides a rare earth magnet in which a layered grain boundary phase is formed on a surface or a potion of a grain boundary of Nd2Fe14B which is a main phase of an R—Fe—B (R is a rare-earth element) based magnet, and wherein the grain boundary phase contains a fluoride compound, and wherein a thickness of the fluoride compound is 10 ?m or less, or a thickness of the fluoride compound is from 0.1 ?m to 10 ?m, and wherein the coverage of the fluoride compound over a main phase particle is 50% or more on average.

Abstract: A powder raw material is prepared by mixing at least two kinds of powders selected from a powder A, a powder B, a powder C, and a powder D. A sintered body of a magnetic material having an NaZn13 crystal structure phase is formed by heating the powder raw material while applying a pressure treatment. The powder A is at least one of elemental powder of element R selected from Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and Yb. The powder B is at least one of elemental powder of element T selected from Fe, Co, Ni, Mn, and Cr. The powder C is at least one of elemental powder of element M selected from Si, B, C, Ge, Al, Ga, and In. The powder D is a compound powder composed of at least two kinds of elements selected from the element R, the element T, and the element M.

Abstract: The present invention provides a technique to improve an adhesion strength between a magnet main body and a protective film. The rare earth sintered magnet of the present invention comprises a magnet main body of a sintered body containing a rare earth element and a protective film formed on the magnet main body, wherein the ratio of a 10-point average surface roughness Rz of the magnet main body on which the protective film is formed to a mean grain size D50 in the magnet main body (Rz/D50 ratio) is kept in a range from 0.20 to 10.00, inclusive. This gives the rare earth sintered magnet which is coated with the protective film having a high adhesion strength of 100 N/m or more and exhibits high corrosion resistance.

Abstract: A rare earth permanent magnet is prepared from a sintered magnet body of a R1—Fe—B composition wherein R1 is a rare earth element inclusive of Y and Sc, by forming a plurality of slits in a surface of the magnet body, disposing a powder on the magnet body surface, the powder comprising an oxide of R2, a fluoride of R3, or an oxyfluoride of R4 wherein each of R2, R3, and R4 is a rare earth element, and heat treating the magnet body and the powder below the sintering temperature in vacuum or in an inert gas.

Abstract: A method of making a magnetically anisotropic magnet powder according to the present invention includes the steps of preparing a master alloy by cooling a rare-earth-iron-boron based molten alloy and subjecting the master alloy to an HDDR process. The step of preparing the master alloy includes the step of forming a solidified alloy layer, including a plurality of R2Fe14B-type crystals (where R is at least one element selected from the group consisting of the rare-earth elements and yttrium) in which rare-earth-rich phases are dispersed, by cooling the molten alloy through contact with a cooling member.

Abstract: To make a raw alloy, consisting mostly of amorphous structure, highly productively and at a reduced cost for a nanocomposite magnet, a molten alloy represented by Fe100-x-y-zRxQyMz (where R is at least one element selected from Pr, Nd, Dy and Tb; Q is B and/or C; M is at least one element selected from Co, Al, Si, Ti, V, Cr, Mn, Ni, Cu, Ga, Zr, Nb, Mo, Ag, Pt, Au and Pb; and 1 at %?x<6 at %, 15 at %?y?30 at % and 0 at %?z?7 at %) is prepared. This molten alloy is rapidly cooled by a strip casting process in which the alloy is fed onto a chill roller, rotating at a peripheral velocity of 3 m/s to less than 20 m/s, at a feeding rate per unit contact width of 0.2 kg/min/cm to 5.2 kg/min/cm. In this manner, an alloy including at least 60 volume percent of amorphous phase can be obtained.

Abstract: An iron-based rare-earth nanocomposite magnet according to the present invention includes an Nd2Fe14B phase and an ?-Fe phase and has a composition represented by the compositional formula: T100-x-y-z-n(B1-qCq)xRyTizMn, where T is at least one transition metal element selected from the group consisting of Fe, Co and Ni and always including Fe, R is at least one rare-earth element including substantially no La or Ce, and M is at least one metal element selected from the group consisting of Al, Si, V, Cr, Mn, Cu, Zn, Ga, Zr, Nb, Mo, Ag, Hf, Ta, W, Pt, Au and Pb, and the mole fractions x, y, z, n and q satisfy the inequalities of: 4 at %?x?10 at %, 6 at %?y?10 at %, 0.05 at %?z?5 at %, 0 at %?n?10 at %, and 0.05?q?0.5, respectively. The magnet includes 5 vol % to 60 vol % of ?-Fe phase with an average crystal grain size of 1 nm to 50 nm and 40 vol % to 90 vol % of Nd2Fe14B phase with an average crystal grain size of 5 nm to 100 nm.