Abstract: A method of manufacturing a rare earth permanent magnet comprises the steps of: forming a rare earth magnet by applying mechanical processing to a magnet block material, thereby damaging the surface of the magnet and causing a magnetic characteristic (BH)max of the magnet to deteriorate, followed by transforming a rare earth metal or an alloy thereof into fine particles or a vapor, and allowing the fine particles or vapor to diffuse and permeate the magnet, thereby improving the quality of the damaged magnet surface portion so that the magnetic characteristic (BH)max is recovered.

Abstract: A method of manufacturing a rare earth permanent magnet comprises the steps of: forming a rare earth magnet by applying mechanical processing to a magnet block material, thereby damaging the surface of the magnet and causing a magnetic characteristic (BH)max of the magnet to deteriorate, followed by transforming a rare earth metal or an alloy thereof into fine particles or a vapor, and allowing the fine particles or vapor to diffuse and permeate the magnet, thereby improving the quality of the damaged magnet surface portion so that the magnetic characteristic (BH)max is recovered.

Abstract: The method for manufacturing alloy powder for R—Fe—B type rare earth magnets of the present invention includes a first pulverization step of coarsely pulverizing a material alloy for rare earth magnets and a second pulverization step of finely pulverizing the material alloy. In the first pulverization step, the material alloy is pulverized by a hydrogen pulverization method. In the second pulverization step, easily oxidized super-fine powder (particle size: 1.0 &mgr;m or less) is removed to adjust the particle quantity of the super-fine powder to 10% or less of the particle quantity of the entire powder.

Abstract: The method for manufacturing alloy powder for R—Fe—B type rare earth magnets of the present invention includes a first pulverization step of coarsely pulverizing a material alloy for rare earth magnets and a second pulverization step of finely pulverizing the material alloy. In the first pulverization step, the material alloy is pulverized by a hydrogen pulverization method. In the second pulverization step, easily oxidized super-fine powder (particle size: 1.0 &mgr;m or less) is removed to adjust the particle quantity of the super-fine powder to 10% or less of the particle quantity of the entire powder.

Abstract: The method for manufacturing alloy powder for R—Fe—B type rare earth magnets of the present invention includes a first pulverization step of coarsely pulverizing a material alloy for rare earth magnets and a second pulverization step of finely pulverizing the material alloy. In the first pulverization step, the material alloy is pulverized by a hydrogen pulverization method. In the second pulverization step, easily oxidized super-fine powder (particle size: 1.0 &mgr;m or less) is removed to adjust the particle quantity of the super-fine powder to 10% or less of the particle quantity of the entire powder.

Abstract: The method for manufacturing alloy powder for R—Fe—B type rare earth magnets of the present invention includes a first pulverization step of coarsely pulverizing a material alloy for rare earth magnets and a second pulverization step of finely pulverizing the material alloy. In the first pulverization step, the material alloy is pulverized by a hydrogen pulverization method. In the second pulverization step, easily oxidized super-fine powder (particle size: 1.0 &mgr;m or less) is removed to adjust the particle quantity of the super-fine powder to 10% or less of the particle quantity of the entire powder.

Abstract: The method for manufacturing alloy powder for R—Fe—B type rare earth magnets of the present invention includes a first pulverization step of coarsely pulverizing a material alloy for rare earth magnets and a second pulverization step of finely pulverizing the material alloy. In the first pulverization step, the material alloy is pulverized by a hydrogen pulverization method. In the second pulverization step, easily oxidized super-fine powder (particle size: 1.0 &mgr;m or less) is removed to adjust the particle quantity of the super-fine powder to 10% or less of the particle quantity of the entire powder.

Abstract: Its basic means is a monolithically bonded construct prepared by monolithically bonding together a rare-earth magnet 2 and a an alloy material that is a high melting point metal or a high specific-tenacity material through the solid phase diffusion bonding by the hot isostatic pressing treatment, and a monolithically bonded construct with an interposal of a thin layer of the high melting point metal between a rare-earth magnet 2 and an alloy material 3, 4 that is a high specific-tenacity material.

Abstract: A process for producing a compound for a rare earth metal resin-bonded magnet includes: a slurry preparation step of mixing materials containing a magnetic alloy powder of a rare earth metal alloy, a resin binder, and an organic solvent into a slurry; and a drying step of spraying and drying the slurry by means of a spray dryer apparatus to produce the compound containing the magnetic alloy powder of the rare earth metal alloy and the resin binder.

Abstract: It is an object of the present invention to provide R-Fe-B permanent magnet materials having a good oxidation resistance and magnetic characteristics, and a process of producing the same capable of pulverizing efficiently, whereby an R-Fe-B molten alloy having a specific composition is casted into a cast piece having a specific plate thickness and a structure, in which an R-rich phase is finely separated below 5 .mu.m, by a strip casting process, the cast piece is subjected to a Hydrogenation for spontaneous decay, and thereafter, an alloy powder is dehydrogenated and stabilized for pulverization so as to fractionize crystal grains of a main phase constituting an alloy ingot, thereby the powder having a uniform grain distribution can be produced at an efficiency of about twice as much as the conventional process, and the R-rich phase and an R.sub.2 Fe.sub.

Abstract: This invention, using finely ground powders obtained by either a ingot grinding method, a Ca reduction diffusion method or a strip casting method, proposes a fabrication method for high-performance R--Fe--B permanent magnets with excellent press packing characteristics, a high degree of orientation of the magnetization direction of each crystallite and a total sum of A, (BH)max (MGOe) and B, iHc (kOe), A+B greater than 59.5. Here, cast alloys or ground alloys are coarse ground by mechanical grinding or by a H.sub.2 absorption and decomposition method, and then fine ground by either mechanical grinding or by a jet mill grinding process to yield R--Fe--B fine powders with an average particle size of 1.0 .mu.m.about.10 .mu.m. These powders are then packed into a mold at a packing density of 1.4.about.3.5 g/cm.sup.

Abstract: To a fine R-Fe-B alloy powder comprised predominantly of 10-30 atomic % of R (wherein R stands for at least one elements selected from rare earth elements including yttrium), 2-28 atomic % of B, and 65-82 atomic % of Fe in which up to 50 atomic % of Fe may be replaced by Co, at least one boric acid ester compound such as tributyl borate is added as a lubricant in a proportion of 0.01%-2% by weight and mixed uniformly before, during, or after fine grinding of the alloy powder. The resulting powder mixture is compacted by compression molding in a magnetic field and the green compacts are sintered and aged. Compression molding can be performed continuously without need of mold lubrication, and the resulting magnets have improved magnet properties with respect to residual flux density, maximum energy product, and intrinsic coercive force.

Abstract: To a fine R--Fe--B alloy powder comprised predominantly of 10-30 atomic % of R (wherein R stands for at least one element selected from rare earth elements including yttrium), 2-28 atomic % of B, and 65-82 atomic % of Fe in which up to 50 atomic % of Fe may be replaced by Co, at least one boric acid ester compound such as tributyl borate is added as a lubricant in a proportion of 0.01%-2% by weight and mixed uniformly before, during, or after fine grinding of the alloy powder. The resulting powder mixture is compacted by compression molding in a magnetic field and the green compacts are sintered and aged. Compression molding can be performed continuously without need of mold lubrication, and the resulting magnets have improved magnet properties with respect to residual flux density, maximum energy product, and intrinsic coercive force.

Abstract: A rare earth alloy for producing permanent magnet comprised of: 15-65 atomic % R.sub.1, 35-83 atomic % Fe, and 0-15 atomic % B, where R.sub.1 represents at least one of heavy rare earth elements Gd, Tb, Dy, Ho, Er, Tm and Yb. This alloy is produced by reducing a mixture of corresponding rare earth oxides, Fe, and a boron containing material by Ca, contacting the reduced mass with water, and treating the resultant slurry with water. Using this alloy, Fe-B-R base magnets wherein R.sub.1 is substituted for part of R (R representing lanthanide and/or Y) having a high performance are produced with a reduced cost.

Abstract: A rare earth-iron-boron alloy powder which consists essentially of:12.5 to 20 at % R wherein R.sub.1 is 0.05 to 5 at %, 4 to 20 at % B, and 60 to 83.5 at % Fe,wherein R.sub.1 is at least one heavy rare earth element selected from the group consisting of Gd, Tb, Dy, Ho, Er, Tm and Yb, 80 to 100 at % of R.sub.2 consists of Nd and/or Pr, the balance in the R.sub.2 being at least one element selected from the group consisting of rare earth elements including Y and except for R.sub.1, and R=R.sub.1 =R.sub.2 by atomic %, wherein a major phase of at least 80 vol % of the entire alloy coinsists of a tetragonal structure, and wherein oxygen does not exceed 10,000 ppm, carbon does not exceed 1000 ppm and calcium does not exceed 2000 ppm. The alloy powder is produced by directly reducing a mixture comprising rare earth oxide, iron and other ingredients or oxide thereof with a reducing agent Ca and CaCl.sub.2, putting the reduced product into water, then treating with water. Up to 35 at % Co may be substituted for Fe.

Abstract: A rare earth alloy for producing permanent magnet comprised of: 15-65 atomic % R.sub.1, 35-83 atomic % Fe, and 0-15 atomic % B, where R.sub.1 represents at least one of heavy rare earth elements Gd, Tb, Dy, Ho, Er, Tm and Yb. This alloy is produced by reducing a mixture of correspoding rare earth oxides, Fe, and a boron containing material by Ca, contacting the reduced mass with water, and treating the resultant slurry with water. Using this alloy, Fe-B-R base magnets wherein R.sub.1 is substituted for part of R (R representing lanthanide and/or Y) having a high performance are produced with a reduced cost.

Abstract: A rare earth-iron-boron alloy powder which consists essentially of:12.5 to 20 at % R wherein R.sub.1 is 0.05 to 5 at %, 4 to 20 at % B, and 60 to 83.5 at % Fe,wherein R.sub.1 is at least one heavy rare earth element selected from the group consisting of Gd, Tb, Dy, Ho, Er, Tm, and Yb, 80 to 100 at % of R.sub.2 consists of Nd and/or Pr, the balance in the R.sub.2 being at least one element selected from the group consisting of rare earth elements including Y and except for R.sub.1, and R=R.sub.1 +R.sub.2 by atomic %, wherein a major phase of at least 80 vol % of the entire alloy coinsists of a tetragonal structure, and wherein oxygen does not exceed 10,000 ppm, carbon does not exceed 1000 ppm and calcium does not exceed 2000 ppm. The alloy powder is produced by directly reducing a mixture comprising rare earth oxide, iron and other ingredients or oxide thereof with a reducing agent Ca and CaCl.sub.2, putting the reduced product into water, then treating with water. Up to 35 at % Co may be substituted for Fe.

Abstract: A permanent magnetic alloy comprising of an intermetallic compound of rare earth elements and transition metals, shown by the formula:R(Ni.sub.x Fe.sub.y Co.sub.1-x-y-z Cu.sub.z).sub.Awherein R is at least one selected from the lanthanide light rare earth elements including Y, such as Y, La, Ce, Pr, Nd and Sm, and0.02.ltoreq.x.ltoreq.0.55x/y=0.07-25.00.01.ltoreq.y.ltoreq.0.650.02.ltoreq.z.ltoreq.0.306.0<A<8.0Preferably, the Ni and Fe are incorporated in substantially equimolar amounts.