A sintered bearing is made of a sintered compact containing nickel silver (Cu—Ni—Zn) as a base. In the sintered bearing, P is not added in the sintered compact. Alternatively, a content of P in the sintered compact is less than 0.05 mass % in terms of mass ratio to a total mass. Consequently, crystal grains constituting the sintered compact can be micronized. In particular, in the sintered bearing, an average crystal particle diameter of the crystal grains constituting the sintered compact is 20 μm or less. Consequently, the mechanical strength and the vibration resisting properties can be improved, and the rotation shaft can be prevented from being damaged.

A powder admixture useful for making a sintered valve seat insert includes a first iron-base powder and second iron-base powder wherein the first iron-base powder has a higher hardness than the second iron-base powder, the first iron-base powder including, in weight percent, 1-2% C, 10-25% Cr, 5-20% Mo, 15-25% Co, and 30-60 wt. % Fe, and the second iron-base powder including, in weight %, 1-1.5% C, 3-15% Cr, 5-7% Mo, 3-6% W, 1-1.7% V, and 60-85% Fe. The powder admixture can be sintered to form a sintered valve seat insert optionally infiltrated with copper.

A powder admixture useful for making a sintered valve seat insert includes a first iron-base powder and second iron-base powder wherein the first iron-base powder has a higher hardness than the second iron-base powder, the first iron-base powder including, in weight percent, 1-2% C, 10-25% Cr, 5-20% Mo, 15-25% Co, and 30-60 wt. % Fe, and the second iron-base powder including, in weight %, 1-1.5% C, 3-15% Cr, 5-7% Mo, 3-6% W, 1-1.7% V, and 60-85% Fe. The powder admixture can be sintered to form a sintered valve seat insert optionally infiltrated with copper.

A sintered magnet body (R.sub.aT.sup.1.sub.bM.sub.cB.sub.d) coated with a powder mixture of an intermetallic compound (R.sup.1.sub.iM.sup.1.sub.j, R.sup.1.sub.xT.sup.2.sub.yM.sup.1.sub.z, R.sup.1.sub.iM.sup.1.sub.jH.sub.k), alloy (M.sup.1.sub.dM.sup.2.sub.e) or metal (M.sup.1) powder and a rare earth (R.sup.2) oxide is diffusion treated. The R.sup.2 oxide is partially reduced during the diffusion treatment, so a significant amount of R.sup.2 can be introduced near interfaces of primary phase grains within the magnet through the passages in the form of grain boundaries. The coercive force is increased while minimizing a decline of remanence.

A sintered magnet body (R.sub.aT.sup.1.sub.bM.sub.cB.sub.d) coated with a powder mixture of an intermetallic compound (R.sup.1.sub.iM.sup.1.sub.j, R.sup.1.sub.xT.sup.2.sub.yM.sup.1.sub.z, R.sup.1.sub.iM.sup.1.sub.jH.sub.k), alloy (M.sup.1.sub.dM.sup.2.sub.e) or metal (M.sup.1) powder and a rare earth (R.sup.2) oxide is diffusion treated. The R.sup.2 oxide is partially reduced during the diffusion treatment, so a significant amount of R.sup.2 can be introduced near interfaces of primary phase grains within the magnet through the passages in the form of grain boundaries. The coercive force is increased while minimizing a decline of remanence.

A composite structure is disclosed comprising a neutron-absorbing metal hydride phase contained within a matrix having a density of greater than 95%. In various embodiments the metal hydride is a hydride of one or more of the following: Gadolinium, Hafnium, Europium, Samarium. The composite structure is utile as a shield for fusion or fission reactors.

A sintered friction material for brake having a high friction coefficient, with which reduction of the friction coefficient is prevented at high temperature and stable brake performance is maintained. It comprises: a metal matrix of Ni or Ni+Fe (small amount); a solid lubricant (a); and a friction adjusting material (b) including: metal or alloy particles (b1) having an average particle size of 50 μm or more and containing at least one selected from W, Mo, Cr, and FeW; and inorganic particles (b2) containing at least one selected from oxides, nitrides, carbides, and intermetallic compounds. An average particle size d.sub.b1 of b1 and an average particle size d.sub.b2 of b2 satisfy d.sub.b1<d.sub.b2. Dispersing, in the metal matrix, b1 and b2 satisfying particular conditions as the friction adjusting material can produce a geometrical structure (particle structure with a high filling density) suitable for preventing plastic deformation of the sintered friction material.

A method for producing a powdered starting material, which is provided for production of rare earth magnets, including includes the following steps: pulverizing an alloy, including at least one rare earth metal, wherein a powdered intermediate product is formed from the alloy including the at least one rare earth metal, and carrying out at least one classification aimed at particle size and/or particle density for the powdered intermediate product. A fraction of the powdered intermediate product, which is formed by the at least one classification, is used for fabrication of rare earth magnets. Furthermore, at least one dynamic classifier is provided, implementing at least one classification directed at particle size and/or particle density for the powdered intermediate product and thereby separates the fraction from the powdered intermediate product, which forms the starting material for manufacturing rare earth magnets.

A method for producing a powdered starting material, which is provided for production of rare earth magnets, including includes the following steps: pulverizing an alloy, including at least one rare earth metal, wherein a powdered intermediate product is formed from the alloy including the at least one rare earth metal, and carrying out at least one classification aimed at particle size and/or particle density for the powdered intermediate product. A fraction of the powdered intermediate product, which is formed by the at least one classification, is used for fabrication of rare earth magnets. Furthermore, at least one dynamic classifier is provided, implementing at least one classification directed at particle size and/or particle density for the powdered intermediate product and thereby separates the fraction from the powdered intermediate product, which forms the starting material for manufacturing rare earth magnets.

Disclosed is a curable composition for the manufacture, by stereolithography, of a green part made of a ceramic or metallic material, the curable composition including at least one ceramic and/or metallic powder; at least one polymerizable monomer and/or oligomer; at least one initiator for the polymerization of the polymerizable monomer(s) and/or oligomer(s). The initiator(s) are selected from iodonium, sulphonium and diazonium salts and onium salts in combination with at least one amine and/or at least one phosphine to form a charge transfer complex. The initiator(s) may generate the initiation of a thermal polymerization under the exposure to at least one source of UV, visible or IR irradiation.