Abstract: An R—Fe—B base sintered magnet is prepared through the steps of providing an alloy fine powder having a predetermined composition, compression shaping the alloy fine powder in an applied magnetic field into a compact, sintering the compact at a temperature of 900-1,250° C. into a sintered body, cooling the sintered body to 400° C. or below, high-temperature heat treatment including placing a metal, compound or intermetallic compound containing HR which is Dy, Tb and/or Ho, on the surface of the sintered body, heating at a temperature from more than 950° C. to 1,100° C., for causing grain boundary diffusion of HR into the sintered body, and cooling to 400° C. or below, and low-temperature heat treatment including heating at a temperature of 400-600° C. and cooling to 300° C. or below. The sintered magnet produces a high coercivity despite a low content of Dy, Tb and Ho.

Abstract: A magnetic compound represented by the formula (R1(1-x)R2x)a(Fe(1-y)Coy)bTcMd wherein R1 is one or more elements selected from the group consisting of Sm, Pm, Er, Tm and Yb, R2 is one or more elements selected from the group consisting of Zr, La, Ce, Pr, Nd, Eu, Gd, Tb, Dy, Ho and Lu, T is one or more elements selected from the group consisting of Ti, V, Mo, Si and W, M is one or more elements selected from the group consisting of unavoidable impurity elements, Al, Cr, Cu, Ga, Ag and Au, 0?x?0.7, 0?y?0.7, 4?a?20, b=100-a-c-d, 0<c<7.7, and 0?d?3, the magnetic compound having a ThMn12-type crystal structure, wherein the volume fraction of ?-(Fe, Co) phase is less than 12.3%.

Abstract: A method for producing a sintered R-iron (Fe)-boron (B) magnet, the method including: (1) producing a sintered magnet R1-Fe—B-M, where R1 is neodymium (Nd), praseodymium (Pr), terbium (Tb), dysprosium (Dy), gadolinium (Gd), holmium (Ho), or a combination thereof; M is titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), cobalt (Co), nickel (Ni), gallium (Ga), calcium (Ca), copper (Cu), Zinc (Zn), silicon (Si), aluminum (Al), magnesium (Mg), zirconium (Zr), niobium (Nb), hafnium (Hf), tantalum (Ta), tungsten (W), molybdenum (Mo), or a combination thereof; (2) removing oil, washing using an acid solution, activating, and washing using deionized water the sintered magnet, successively; (3) mixing a superfine terbium powder, an organic solvent, and an antioxidant to yield a homogeneous slurry, coating the homogeneous slurry on the surface of the sintered magnet; and (4) sintering and aging the sintered magnet.

Abstract: The present invention provides a rare earth based magnet that inhibits the high temperature demagnetization rate even when less or no heavy rare earth elements such as Dy, Tb and the like are used. The rare earth based magnet according to the present invention includes R2T14B main phase crystal grains and grain boundary phases between adjacent main phase crystal grains. In any cross-section of the rare earth based magnet, when evaluating the circular degree of the main phase crystal grains with Wadell's Roundness A, the shape of the main phase crystal grains is controlled such that the Roundness A becomes 0.24 or more.

Abstract: The invention provides an R—Fe—B sintered magnet consisting essentially of 12-17 at % of Nd, Pr and R, 0.1-3 at % of M1, 0.05-0.5 at % of M2, 4.8+2*m to 5.9+2*m at % of B, and the balance of Fe, containing R2(Fe,(Co))14B intermetallic compound as a main phase, and having a core/shell structure that the main phase is covered with grain boundary phases. The sintered magnet exhibits a coercivity of at least 10 kOe despite a low or nil content of Dy, Tb and Ho.

Abstract: According to one embodiment, a permanent magnet is provided with a sintered body having a composition represented by R(FepMqCurCo1-p-q-r)zOw (where, R is at least one element selected from rare-earth elements, M is at least one element selected from Ti, Zr and Hf, and p, q, r, z and w are numbers satisfying 0.25?p?0.6, 0.005?q?0.1, 0.01?r?0.1, 4?z?9 and 0.005?w?0.6 in terms of atomic ratio). The sintered body has therein aggregates of oxides containing the element R dispersed substantially uniformly.

Abstract: Provided is a neodymium-based rare earth permanent magnet having a purity of 99.9 wt % or higher excluding gas components and component elements. The present invention can remarkably improve the magnetic properties in a neodymium-based rare earth permanent magnet by highly purifying the magnetic materials. Furthermore, the present invention aims to provide a high-performance neodymium-based rare earth permanent magnet with improved heat resistance and corrosion resistance, which are inherent drawbacks of magnetic materials.

Abstract: An electromagnetic relay (100) has high wear resistance, high corrosion resistance, and good magnetic properties. The electromagnetic relay (100) includes a magnetic component including an alloy layer on its surface formed by diffusion-coating of at least one element selected from the group consisting of Cr, V, Ti, and Al. The alloy layer has a thickness of 5 to 60 ?m, inclusive.

Abstract: Provided herein are systems, methods, and compositions for magnetic nanoparticles and bulk nanocomposite magnets.

Abstract: A method for producing a NdFeB system sintered magnet in which a coating material containing a heavy rare-earth element RH applied to a base material of a NdFeB system sintered magnet is inexpensively prevented from adhering to a tray or similar device in a grain boundary diffusion treatment. The method includes the steps of applying a coating material containing a heavy rare-earth element RH to a base material and diffusing the element through grain boundaries in the base material by a grain boundary diffusion method. The coating material is applied to a sheet. The sheet is made to come in tight contact with the base material so that the coating material applied to the sheet contacts an application target surface of the base material. With the sheet held in tight contact with the base material, the grain boundary diffusion treatment (heat treatment) is performed on the base material.

Abstract: According to one embodiment, a permanent magnet is provided with a sintered body having a composition represented by R(FepMqCurCo1-p-q-r)zOw (where, R is at least one element selected from rare-earth elements, M is at least one element selected from Ti, Zr and Hf, and p, q, r, z and w are numbers satisfying 0.25?p?0.6, 0.005?q?0.1, 0.01?r?0.1, 4?z?9 and 0.005?w?0.6 in terms of atomic ratio). The sintered body has therein aggregates of oxides containing the element R dispersed substantially uniformly.

Abstract: An R—Fe—B based thin film magnet including an R—Fe—B based alloy which contains 28 to 45 percent by mass of R element (where R represents at least one type of rare-earth lanthanide elements) and which is physically formed into a film, wherein the R—Fe—B based alloy has a composite texture composed of R2Fe14B crystals having a crystal grain diameter of 0.5 to 30 ?m and R-element-rich grain boundary phases present at boundaries between the crystals. The magnetization characteristics of the thin film magnet are improved. The R—Fe—B based thin film magnet can be prepared by heating to 700° C. to 1,200° C. during physical film formation or/and the following heat treatment, so as to grow crystal grains and form R-element-rich grain boundary phases.

Abstract: A high strength and creep resistant soft magnetic Fe—Co alloy includes, in weight %, Fe and Co such that the difference between the Fe and Co is at least 2%, at least 35% Co, and 2.5%?(V+Mo+Nb), wherein 0.4%?Mo and/or 0.4%?Nb. This alloy can further include B, C, W, Ni, Ti, Cr, Mn and/or Al. A vanadium-free high strength soft magnetic Fe—Co alloy includes in weight %, Fe and Co such that the difference between the Fe and Co is at least 2%, and at least 15% Co, the alloy further satisfying (0.1%?Nb and 0.1%?W) or 0.25%?Mn. This alloy can further include B, C, Ni, Ti, Cr and/or Al.

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: A rare-earth alloy ingot is produced by melting an alloy composed of 20-30 wt % of a rare-earth constituent which is Sm alone or at least 50 wt % Sm in combination with at least one other rare-earth element, 10-45 wt % of Fe, 1-10 wt % of Cu and 0.5-5 wt % of Zr, with the balance being Co, and quenching the molten alloy in a strip casting process. The strip-cast alloy ingot has a content of 1-200 ?m size equiaxed crystal grains of at least 20 vol % and a thickness of 0.05-3 mm. Rare-earth sintered magnets made from such alloys exhibit excellent magnetic properties and can be manufactured under a broad optimal temperature range during sintering and solution treatment.

Abstract: The present invention provides a tempering process for sintered Nd—Fe—B permanent magnet material, which optimizes the microstructure of the Nd—Fe—B magnet and improves intrinsic coercive force and its consistency by increasing the cooling rate after tempering. After heating to a temper temperature, the magnetic material is cooled in a cooling liquid within a cooling chamber into which a pressurized cooling gas is introduced.

Abstract: A rare earth magnet comprises rare earth magnet particles and a rare earth oxide being present between the rare earth magnet particles. The rare earth oxide is represented by a following general formula (I): R2O3??(I) where R is any one of terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium.

Abstract: A method of making a sintered body for a rare earth magnet includes the steps of (a) preparing a first coarse powder by coarsely pulverizing a rare earth alloy sintered body by a hydrogen pulverization process, (b) preparing a first fine powder by finely pulverizing the first coarse powder, (c) preparing a second fine powder by pulverizing an alloy block of a rare earth alloy material, and (d) sintering a mixed powder including the first and second fine powders. The first and second fine powders each includes a main phase represented by (LR1-xHRx)2T14A, where T is Fe and/or at least one non-Fe transition metal element; A is boron and/or carbon; LR is at least one light rare earth element; HR is at least one heavy rare earth element; and 0?x<1.

Abstract: A powder compacting method includes the steps of: providing a powder material; loading the powder material into a cavity; uniaxially pressing the powder material, which has been loaded into the cavity, between two opposed press surfaces, thereby obtaining a compact, wherein at least one of the two press surfaces is deformed elastically under a compacting pressure when contacting with the powder material in the cavity; and unloading the compact from the cavity. According to this powder compacting method, even when the powder material has a non-uniform fill density distribution, a compact with a uniform density distribution can be obtained at a high productivity.

Abstract: An apparatus for subjecting a rare earth alloy block to a hydrogenation process includes a casing, gas inlet and outlet ports, a member arranged to produce a gaseous flow, and a windbreak plate. The casing defines an inner space for receiving a container. The container includes an upper opening and stores the rare earth alloy block therein. A hydrogen gas and an inert gas are introduced into the inner space through the gas inlet port, and are exhausted from the inner space through the gas outlet port. The gaseous flow is produced by a fan, for example, in the inner space. The windbreak plate is disposed upstream with respect to the gaseous flow that has been produced inside the inner space. Also, the windbreak plate reduces a flow rate of the gaseous flow that has been produced near the upper opening of the container.

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: A method of producing a sintered rare earth magnetic alloy wafer comprises a step of using a cutter to slice a wafer of a thickness of not greater than 3 mm from a sintered rare earth magnetic alloy having ferromagnetic crystal grains surrounded by a more readily grindable grain boundary phase and a step of surface-grinding at least one cut surface of the obtained wafer with a grindstone to form at a surface layer thereof flat ferromagnetic crystal grain cross-sections lying parallel to the wafer planar surface. The method enables high-yield production of a sintered rare earth magnetic alloy wafer having flat surfaces.

Abstract: To provide a method for producing a magnetostrictive material of excellent magnetostrictive characteristics. The method for producing a magnetostrictive material, wherein a mixture composed of Starting Materials A, B and C is sintered, where A is represented by Formula 1 (TbxDy1-x)Ty (T is at least one metallic element selected from the group consisting of Fe, Ni and Co, 0.35<x?0.50 and 1.70?y?2.00), B is represented by Formula 2 DytT1-t (0.37?t?1.00), and C contains T, to produce a magnetostrictive material represented by Formula 3 (TbvDy1-v)Tw (0.27?v<0.50, and 1.70?w?2.00), wherein oxygen content is set at 500 to 3,000 ppm for Starting Material A and at 2,000 to 7,000 ppm for Starting Material B.

Abstract: A rare earth magnet to be used in a motor. The rare earth magnet comprises rare earth magnet particles. Additionally, a rare earth oxide is present among the rare earth magnet particles, the rare earth oxide being represented by the following general formula (I): R2xR?2(1?x)O3??(I) where each of R and R? is one element selected from the group consisting of yttrium (Y), lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb) and lutetium (Lu), and 0<x<1.

Abstract: The present invention relates to a high performance rare earth-iron giant magnetostrictive material of the formula (Tbx1Dyx2Smx3Hox4Rx5)(Sy1Py2Fe1-y1-y2-y3Ty3)Q obtained by using an industry grade pure iron, instead of physically pure iron such as electrolyzed pure iron or hydrogen reduced pure iron, as iron source. The invention relates also to a method of preparing the giant magnetostrictive material.

Abstract: A method of making a material alloy for an iron-based rare earth magnet includes the step of forming a melt of an alloy with a composition of (Fe1-mTm)100-x-y-z-n(B1-pCp)xRyTi2Mn. T is Co and/or Ni; R is at least one element selected from Y (yttrium) and the rare earth elements; and M is at least one element selected from Al, Si, V, Cr, Mn, Ni, Cu, Zn, Ga, Zr, Nb, Mo, Ag, Hf, Ta, W, Pt, Au and Pb, wherein the following inequalities are satisfied: 10<x?25 at %, *6?y<10 at %, 0.5?z?12 at %, 0?m?0.5, 0?n?10 at % and 0?p?0.25. Next, the melt is fed onto a shoot with a guide surface tilted at about 1 degree to about 80 degrees with respect to a horizontal plane, thereby moving the melt onto a melt/roller contact region. The melt is then rapidly cooled using a chill roller to make a rapidly solidified alloy including an R2Fe14B phase.

Abstract: A Nd—Fe—B type rare earth magnet alloy is provided with hard magnetic phases each of which has a size equal to or less than 80 nm, soft magnetic phases each of which has a size equal to or less than 80 nm, with the hard and soft magnetic phases being present in a mixed structure, and partly anisotropic regions wherein axes of easy magnetization of the hard magnetic phases are aligned in one direction and each having a size equal to or greater than 0.1 &mgr;m. Such a magnet alloy is obtained using a strip casting method or ultra cooling method and serves as material for an anisotropic exchange spring magnet to be applied to a motor.

Abstract: A magnetic powder of an Sm—Fe—N alloy, which has a mean particle diameter of 0.5 to 10 &mgr;m, and either an average acicularity of 75% or above or an average sphericity of 78% or above. The powder exhibits an extremely high residual magnetization and an extremely high coercive force, since particles characterized by the above acicularity or sphericity have particle diameters approximately equal to that of the single domain particle and nearly spherical particle shapes. The powder can be produced by preparing an Sm—Fe oxide by firing a coprecipitate corresponding to the oxide, mixing the obtained oxide with metallic calcium and subjecting the mixture to reduction/diffusion and nitriding successively.

Abstract: On a surface of a rare earth permanent magnet R—T—M—B wherein R is a rare earth element, T is Fe or Fe and Co, M is Ti, Nb, Al, V, Mn, Sn, Ca, Mg, Pb, Sb, Zn, Si, Zr, Cr, Ni, Cu, Ga, Mo, W or Ta, 5 wt %≦R≦40 wt %, 50 wt %≦90 wt %, 0 wt %≦M≦8 wt %, and 0.2 wt %≦B≦8 wt %, a solution comprising a flake fine powder of Al, Mg, Ca, Zn, Si, Mn or an alloy thereof and a silicone resin is applied and baked to form an adherent composite coating, thereby providing a corrosion resistant rare earth permanent magnet.

Abstract: A powder for forming a R—Fe—B bonded magnet, wherein an R compound, such as an R oxide, an R carbide, an R nitride or an R hydride, which is contained in a raw material powder such as a super rapidly cooled powder or a hydrogen treated powder (HDDR powder) and reacts with water vapor to change into R(OH)3, has been converted to a R hydroxide R(OH)3 being stable in the air by subjecting the raw material powder to a heat treatment in an atmosphere of a pressured water vapor. The powder for forming an R—Fe—B bonded magnet is free from the generation of a white powder in the surface of or inside a bonded magnet formed from the powder and accordingly, is free from the occurrence or cracking, chipping, swelling or the like in the bonded magnet caused by volume expansion of a white powder.

Abstract: An R—Fe—B permanent magnet wherein R is Nd or a combination of Nd with a rare earth element is prepared by casting an R—Fe—B alloy, crushing the alloy in an oxygen-free atmosphere of argon, nitrogen or vacuum, effecting comminution, compaction, sintering, aging, and cutting and/or polishing the magnet to give a finished surface. The magnet is then heat treated in an argon, nitrogen or low-pressure vacuum atmosphere having a limited oxygen partial pressure, obtaining a highly oil resistant sintered permanent magnet having corrosion resistance and hydrogen barrier property even in a high pressure hot environment of refrigerant and/or lubricant as encountered in compressors.

Abstract: A melt of an iron-based rare earth material alloy, represented by (Fe1-mTm)100-x-y-zQxRyMz, is prepared, wherein T is Co and/or Ni; Q is B and/or C; R is selected from Y (yttrium) and the rare earth elements; M is selected from Al, Si, Ti, V, Cr, Mn, Cu, Zn, Ga, Zr, Nb, Mo, Ag, Hf, Ta, W, Pt, Au and Pb; 10≦x≦30 at %; 2%≦y<10 at %; 0≦z≦10 at % and 0≦m≦0.5. The melt is fed onto a guide to form a flow of the melt thereon and move the melt onto a melt/chill roller contact region, where the melt is rapidly cooled by the chill roller to make a rapidly solidified alloy. An oxygen concentration of the melt yet to be fed onto the guide is controlled at about 3,000 ppm or less in mass percentage.

Abstract: An alloy powder for bonded rare earth magnets is prepared by melting an alloy consisting essentially of 20-30 wt % of Sm or a mixture of rare earth elements (inclusive of Y) containing at least 50 wt % of Sm, 10-45 wt % of Fe, 1-10 wt % of Cu, 0.5-5 wt % of Zr, and the balance of Co, quenching the melt by a strip casting technique, to form a rare earth alloy strip containing at least 20% by volume of equiaxed crystals with a grain size of 1-200 &mgr;m and having a gage of 0.05-3 mm, and heat treating the strip in a non-oxidizing atmosphere at 1000-1300° C. for 0.5-20 hours, followed by aging treatment and grinding.

Abstract: The inventive method for preparing nanocomposite magnet powder includes the step of preparing material alloy powder for a nanocomposite magnet represented by a general formula Fe100−x−y−z−uRxByCozMu where R is a rare-earth element of which 90-100 atomic percent is Pr and/or Nd while 0-10 atomic percent is another lanthanoid and/or Y, and the molar fractions x, y, z and u meet the inequalities of 2≦x≦6, 16≦y≦20, 0.2≦z≦7 and 0.01≦u≦7, respectively. The powder includes a metastable phase and an amorphous structure existing in a metal structure. Heat treatment is performed for the material alloy powder to crystallize Fe3B and Fe—R—B compounds from the amorphous structure. An integral value of the difference between a temperature-time curve represented by the temperature of the material alloy powder as a function of the heat treatment time during the heat treatment and a reference temperature-time curve is in a range from 10° C.

Abstract: Disclosed is a magnetically anisotropic rare earth-based permanent magnet having a nanocomposite structure consisting of fine dispersion of a magnetically hard phase, e.g., Nd2Fe14B, in alignment relative to the easy magnetization axis, a magnetically soft phase and a non-magnetic phase having a melting point lower than those of the magnetically hard and soft phases. The permanent magnet is prepared in a process in which a quenched thin magnet alloy ribbon having a composition capable of forming a magnetically hard phase, magnetically soft phase and non-magnetic phase by a heat treatment is subjected to a heat treatment in a magnetic field of at least 3 T at a temperature not lower than the melting point of the non-magnetic phase so that the liquid phase formed from the non-magnetic phase serves to facilitate rotating orientation of the magnetically hard grains to be aligned in the direction of the magnetic field relative to the easy magnetization axis.

Abstract: An R—Fe—B permanent magnet wherein R is Nd or a combination of Nd with a rare earth element is prepared by casting an R—Fe—B alloy, crushing the alloy in an oxygen-free atmosphere of argon, nitrogen or vacuum, effecting comminution, compaction, sintering, aging, and cutting and/or polishing the magnet to give a finished surface. The magnet is then heat treated in an argon, nitrogen or low-pressure vacuum atmosphere having a limited oxygen partial pressure, obtaining a highly oil resistant sintered permanent magnet having corrosion resistance and hydrogen barrier property even in a high pressure hot environment of refrigerant and/or lubricant as encountered in compressors.

Abstract: The present invention is directed to an alloy for a high-performance rare earth permanent magnet. This alloy has a metallographic structure of approximately two phases that comprises a Nd2Fe14B phase (1) consisting of hard magnetic crystal grains and an &agr;-Fe phase (2) consisting of soft magnetic crystal grains. The metallographic structure has an ultra-thin film (3) that contains a large amount of nonmagnetic metallic elements that have an atomic radius of between the atomic radius of Fe and the atomic radius of Nd at each of the crystal grain boundaries between the phases (1, 2) and that will not form solid solutions with either Fe or Nd. The nonmagnetic metallic elements consist of one or two or more elements selected from among Nb, Zr, Ta and Hf, the thickness of each ultra-thin film is 10 to 20 angstroms, and the sizes of the crystal grains in each of the phases (1, 2) are in the range 5 to 100 nm, preferably 10 to 40 nm.

Abstract: A ferromagnetic powder composition for dust cores contains a ferromagnetic metal powder and 0.1-15% by volume based on the powder of titania sol and/or zirconia sol. The composition is pressure molded and desirably annealed into a dust core which exhibits a high magnetic flux density, low coercivity, low loss and high mechanical strength.

Abstract: The object of the invention is to provide a composition for permanent magnet with excellent magnetic properties exhibiting well the latent ability of the RFeB system tetragonal compounds. The composition for permanent magnet according to the present invention is a complex of (1) a crystalline RFeB or RFeCoB system compound having a tetragonal crystal structure with lattice constants of a.sub.o about 8.8 .ANG. and c.sub.o about 12 .ANG., in which R is at least one of rare earth elements, and (2) a crystalline neodymium oxide having a cubic crystal structure, in which both crystal grains are epitaxially connected and the RFeB or RFeCoB crystal grains are oriented to the c.sub.o direction. The lattice constant a.sub.o of the cubic Nd.sub.2 O.sub.3 is about 4.4 .ANG. which is the half length of the lattice constant a.sub.o about 8.8 .ANG. for the RFeB or RFeCoB tetragonal crystal, and the epitaxial connection is achieved, and the RFeB or RFeCoB crystal grains are oriented to the c.sub.o direction.

Abstract: Bonded magnets made from gas atomized powders of an rare earth alloy and having good hard magnetic characteristics are provided. The powders have an alloy composition comprising approximately 15 to 34 weight % of RE, 0.8 to 1.2 weight % of B, 0.5 to 4 weight % of TiC, balanced with at least one of Fe and Co, wherein RE is one or more rare earth elements selected from the group consisting of Y, La, Ce, Pr, Nd, Sm, Er, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu.

Abstract: A high-frequency composite material, having soft magnetic and dielectric characteristics, comprising a soft magnetic alloy powder represented by the general composition A.sub.a M.sub.b D.sub.c and a synthetic resin, wherein A represents at least one element or mixture thereof selected from the group consisting of Fe, Co and Ni; M represents at least one element or mixture thereof selected from the group consisting of Hf, Zr, W, Ti, V, Nb, Mo, Cr, Mg, Mn, Al, Si, Ca, Sr, Ba, Cu, Ga, Ge, As, Se, Zn, Cd, In, Sn, Sb, Te, Pb, Bi and rare earth elements; D represents at least one element or mixture thereof selected from the group consisting of O, C, N and B; and the suffixes a, b, and c in the general formula A.sub.a M.sub.b D.sub.c satisfy the following equations represented by atomic percent: 40.ltoreq.a<80, 0.ltoreq.b.ltoreq.30, and 0<c.ltoreq.50.

Abstract: A rare earth iron permanent magnet including at least one rare earth element, iron and boron as primary ingredients. The magnet can have an average grain diameter of less than or equal to about 150 .mu.m and a carbon content of less than or equal to about 400 ppm and content of less than or equal to about 1000 ppm. The permanent magnet is prepared by casting a molten alloy. In one embodiment, the cast body is heat treated at a temperature of greater than or equal to about 250.degree. C. Alternatively, the material can be cast and hot worked at a temperature of greater than or equal to about 500.degree. C. Finally, the material can be cast, hot worked at a temperature of greater than or equal to about 500.degree. C. and then heat treated at a temperature of greater than or equal to about 250.degree. C. The magnets provided in accordance with the invention are relatively inexpensive to produce an have excellent performance characteristics.

Abstract: A process for manufacturing an Alnico system permanent magnet is disclosed in which the alloy powder of the Alnico system having the proper composition is manufactured through a rapid solidification process, so that the crushability and the formability should be superior, the sintered density should be high, and the magnetic properties should be excellent, as well as cheap in its manufacturing cost and simple in its manufacturing process. An alloy of Alnico system is subjected to a rapid solidification with a spinning solidifier wheel speed of 6-40 m/sec, thereby manufacturing a microcrystalline rapidly solidified powder. The powder is ground into a finer powder, and then a press-forming is carried out. Then a sintering is carried out at a temperature of 1100.degree.-1350.degree. C. for 0.5-4 hours. Then based on a single heat treatment, an external magnetizing force of 1-15 kOe is applied in a temperature range of 600.degree.-1000.degree. C., thereby carrying out a heat treatment under a magnetizing force.

Abstract: A magnetically anisotropic R-T-B-M powder material which is starting with an R-T-B-M raw alloy material having a c-axis crystal orientation of an R.sub.2 T.sub.14 B-type intermetallic compound phase. In one embodiment, the starting material is compressed sintered in a magnetic field and recompressed in a magnetic field. In a second embodiment, the starting material is hot-pressed and homogenized. A method of manufacturing anisotropic magnets such as bond and full density magnets made from the magnetically anisotropic R-T-B-M powder material is disclosed.

Abstract: A method of making a permanent magnet wherein 1) a melt is formed having a base alloy composition comprising RE, Fe and/or Co, and B (where RE is one or more rare earth elements) and 2) TR (where TR is a transition metal selected from at least one of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, and Al) and at least one of C and N are provided in the base alloy composition melt in substantially stoichiometric amounts to form a thermodynamically stable compound (e.g. TR carbide, nitride or carbonitride). The melt is rapidly solidified in a manner to form particulates having a substantially amorphous (metallic glass) structure and a dispersion of primary TRC, TRN and/or TRC/N precipitates. The amorphous particulates are heated above the crystallization temperature of the base alloy composition to nucleate and grow a hard magnetic phase to an optimum grain size and to form secondary TRC, TRN and/or TRC/N precipitates dispersed at grain boundaries.

Abstract: A method for the preparation of alloys of the SE.sub.2 Fe.sub.17-x TM.sub.xN.sub.y type where SE stands for a rare earth metal, including Y or a mixture of these metals, while TM stands for Co, Ni, Cu, Zr, Ga, Hf, Ta, Nb, Ti, Si, A1, V, Mo, Cr, Zn or Sn or a mixture of these metals, x=0 to 10, y=>0 to 5 is described. The preparation involves calciothermal reduction of a finely divided, homogeneous mixture of the alloying components, subsequent diffusion of the components, followed by nitriding and separating the calcium oxide and excess calcium formed. The method is characterized by:a) Preparation of an alloy of the SE.sub.2 Fe.sub.17-x TM.sub.x bya1) Adjusting the exothermic reaction of the calciothermal reduction by the oxide content of the reaction mixture, so that T.sub.M >TR .gtoreq.0.9 T.sub.M where T.sub.M is the melting temperature of the intermetallic phase, and T.sub.

Abstract: A process is provided for modifying the magnetic properties of an intermetallic compound comprising at least iron, or a combination of iron with at least one transition metal, and at least one rare earth element. The process comprises heating the intermetallic compound in a reaction gas containing at least one element of groups IIIA, IVA or VIA of the Periodic Table in the gaseous phase to interstitially incorporate the element or elements of these groups into the crystal lattice of the intermetallic compound. Novel magnetic materials showing easy uniaxial anisotropy, increased spontaneous magnetization and Curie temperatures are produced by the process.

Abstract: A method is provided for forming high coercivity permanent magnets from a rare earth-iron-boron metal, wherein the permanent magnets exhibit high intrinsic coercivity comparable to that of the rare earth-iron-boron metal alloy when formed by machining and appropriately heat treating the metal alloy in air at a temperature greater than the Curie temperature of the material, prior to or after the machining operation. As a result, high coercivity permanent magnets can be selectively sized and shaped to satisfy specific design requirements, without requiring that a punch and die be specially designed and manufactured to produce the permanent magnets. The heat treatment method is able to promote machinability of the metal alloy without substantially causing a loss in magnetic properties. Alternatively, the heat treatment method can be employed to substantially restore the magnetic properties of a permanent magnet which were previously reduced by conventional annealing practices.

Abstract: A magnetically anisotropic sintered permanent magnet of the FeCoBR system (R is sum of R.sub.1 and R.sub.2) wherein:R.sub.1 is Dy, Tb, Gd, Ho, Er, Tm and/or Yb, andR.sub.2 comprises 80 at % or more of Nd and Pr in R.sub.2, and the balance of other rare earth elements exclusive of R.sub.1,said system consisting essentially of, by atomic percent, 0.05 to 5% of R.sub.1, 12.5 to 20% of R, 4 to 20% of B up to 35% of Co, and the balance being Fe. Additional elements M(Ti, Zr, Hf, Cr, Mn, Ni, Ta, Ge, Sn, Sb, Bi, Mo, Nb, Al, V, W) may be present.

Abstract: A rare earth permanent magnet of a composition, Ce(CO.sub.1-x-y-a Fe.sub.x Cu.sub.y M.sub.a).sub.z, where a, x, y, and z are: 0.005<1<0.10; 0.20<x<0.40; 0.10<y<0.30; 4.8<z<6.0; and M is zirconium, titanium, nickel, and/or manganese. A method for manufacturing the magnet is disclosed comprising the steps of: applying a first solid solution heat treatment to an alloy ingot having the above composition at temperatures from 900.degree. to 1100.degree. C. for 10 minutes to 100 hours; pulverizing the alloy ingot; obtaining a magnet body from this pulverized alloy by the powder metallurgy method; sintering the magnet body; applying a second solid solution heat treatment to the sintered magnet body at 900.degree.-100.degree. C. for 10 minutes to 100 hours; and applying aging heat treatment to the sintered magnet.