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: Isotropic permanet magnet formed of a sintered body having a mean crystal grain size of 1-130 microns and a major phase of tetragonal system comprising, in atomic percent, 10-25% of R wherein R represents at least one of rare-earth elements including Y, 3-23% of B, no more than 50% of Co and the balance being Fe. As additional elements M, Al, Ti, V, Cr, Mn, Zr, Hf, Nb, Ta, Mo, Ge, Sb, Sn, Bi, Ni or W may be incorporated.The magnets can be produced through a powder meallurgical process resulting in high magnetic properties, e.g., up to 7 MGOe or higher energy product.

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: Permanent magnet materials of the Fe-B-R type are produced by:preparing a metallic powder having a mean particle size of 0.3-80 microns and a composition of 8-30 at % R, 2-28 at % B, and the balance Fe,compacting, andsintering, at a temperature of 900-1200 degrees C. Co up to 50 at % may be present. Additional elements M (Ti, Ni, Bi, V, Nb, Ta, Cr, Mo, W, Mn, Al, Sb, Ge, Sn, Zr, Hf) may be present. The process is applicable for anisotropic and isotropic magnet materials.

Abstract: A sintered Fe-Cr-Co type magnetic alloy consisting essentially of 20-35% Cr, 3-15% Co and the balance substantially of Fe and a method of producing an article made of the alloy are disclosed. The method comprises the steps of blending at least one of an Fe-Cr powder and Fe-Cr-Co powder with a carbonyl Fe-powder and a Co-powder, if necessary to make up to said alloy composition, to provide a powder blend, the average particle size of said Fe-Cr powder and Fe-Cr-Co powder being 200 mesh or smaller in size, and the surface of these powders having been activated; compacting the resulting powder blend to provide a compact; sintering the resulting compact in an atmosphere in which the total amount of oxygen and nitrogen has been restricted to not more than 3 ppm; and effecting the heat treatment and magnetization of the resulting sintered alloy.

Abstract: Permanent magnetic materials of the Fe-B-R type are produced by:preparing an metallic powder having a mean particle size of 0.3-80 microns and a composition of, by atomic percent, 8-30% R (rare earth elements), 2-28% B, and the balance Fe, compacting, sintering at a temperature of 900-1200 degrees C., and aging at a temperature ranging from 350 degrees C. to the temperature for sintering. Co and additional elements M (Ti, Ni, Bi, V, Nb, Ta, Cr, Mo, W, Mn, Al, Sb, Ge, Sn, Zr, Hf) may be present.

Abstract: Permanent magnet materials of the Fe-B-R type are produced by:preparing a metallic powder having a mean particle size of 0.3-80 microns and a composition of 8-30 at % R, 2-28 at % B, and the balance Fe,compacting, andsintering, at a temperature of 900-1200 degrees C.Co up to 50 at % may be present. Additional elements M (Ti, Ni, Bi, V, Nb, Ta, Cr, Mo, W, Mn, Al, Sb, Ge, Sn, Zr, Hf) may be present. The process is applicable for anisotropic and isotropic magnet materials.