A sintered bearing includes, on an inner peripheral surface, a cylindrical portion and a one-side increased-diameter portion, which are provided so as to be continuous in the axial direction. An end portion of one side in the axial direction of the cylindrical portion and an end portion of another side in the axial direction of the increased-diameter portion coincide, and the cylindrical portion and the increased-diameter portion are molded by performing sizing on a sintered compact having a tubular shape, which is introduced into a die.

An insulator-coated soft magnetic powder includes core particles each of which includes a base portion containing a soft magnetic material and an oxide film provided on the surface of the base portion and containing an oxide of an element contained in the soft magnetic material, ceramic particles which are provided on the surface of each of the core particles and have an insulating property, and a glass material which is provided on the surface of each of the core particles, has an insulating property, and contains at least one type of phosphorus oxide, bismuth oxide, zinc oxide, boron oxide, tellurium oxide, and silicon oxide as a main component, wherein the ceramic particles are included in a proportion of 100 vol % or more and 500 vol % or less of the glass material.

To provide an apparatus for producing a metal powder and a method of producing a metal powder capable of obtaining a metal powder having a finer particle size of excellent quality. A supersonic combustion flame is intensively injected into a downwardly supplied molten metal, the intensive combustion flame is jetted directly downwardly as a focused jet flow, the focused jet flow thrusts into a turning water flow formed along an inner peripheral surface of a pulverization cooling cylinder whose axis line is inclined from a vertical direction, and an intensive position of the combustion flame is in an open space above the turning water flow.

A metal powder contains not less than 0.10 mass % and not more than 1.00 mass % of at least one of chromium and silicon, and a balance of copper. The total content of the chromium and the silicon is not more than 1.00 mass %. In accordance with an additive manufacturing method for this metal powder, an additively-manufactured article made from a copper alloy is provided. The additively-manufactured article has both an adequate mechanical strength and an adequate electrical conductivity.

A metal powder contains not less than 0.10 mass % and not more than 1.00 mass % of at least one of chromium and silicon, and a balance of copper. The total content of the chromium and the silicon is not more than 1.00 mass %. In accordance with an additive manufacturing method for this metal powder, an additively-manufactured article made from a copper alloy is provided. The additively-manufactured article has both an adequate mechanical strength and an adequate electrical conductivity.

A production method for water-atomized metal powder includes: in a region in which the average temperature of a molten metal stream is higher than the melting point by 100° C. or more, spraying primary cooling water from a plurality of directions at a convergence angle of 10° to 25°, where the convergence angle is an angle between an impact direction on the molten metal stream of the primary cooling water from one direction and an impact direction on the molten metal stream of the primary cooling water from any other direction; and in a region in which 0.0004 seconds or more have passed after an impact of the primary cooling water and the average temperature of metal powder is the melting point or higher and (the melting point+50° C.) or lower, spraying secondary cooling water on the metal powder under conditions of an impact pressure of 10 MPa or more.

A production method for water-atomized metal powder includes: in a region in which the average temperature of a molten metal stream having an Fe concentration of 76.0 at % or more and less than 82.9 at % is 100° C. or more higher than the melting point, spraying primary cooling water at a convergence angle of 10° to 25°, where the convergence angle is an angle between an impact direction on the molten metal stream from one direction and an impact direction on the molten metal stream from any other direction; and in a region in which 0.0004 seconds or more have passed after an impact of the primary cooling water and the average temperature of metal powder is the melting point or higher and (the melting point+100° C.) or lower, spraying secondary cooling water on the metal powder under conditions of an impact pressure of 10 MPa or more.

A porous amorphous silicon which enables improvement in battery performances such as charge/discharge efficiency and battery capacity when used as the anode material; a method for producing a porous amorphous silicon, capable of producing a porous amorphous silicon composed entirely of amorphous silicon at relatively low cost in a short time; and a secondary battery using the porous amorphous silicon as the anode material. A molten metal containing metal and silicon is cooled at a cooling rate of 10.sup.6 K/sec or more to form an eutectic alloy including the metal and the silicon, and then the metal is selectively eluted from the eutectic alloy with an acid or an alkali to obtain a porous amorphous silicon. The porous amorphous silicon has a lamellar or columnar structure having a mean lamellar diameter or a mean column diameter of 1 nm to 100 nm.

A porous amorphous silicon which enables improvement in battery performances such as charge/discharge efficiency and battery capacity when used as the anode material; a method for producing a porous amorphous silicon, capable of producing a porous amorphous silicon composed entirely of amorphous silicon at relatively low cost in a short time; and a secondary battery using the porous amorphous silicon as the anode material. A molten metal containing metal and silicon is cooled at a cooling rate of 10.sup.6 K/sec or more to form an eutectic alloy including the metal and the silicon, and then the metal is selectively eluted from the eutectic alloy with an acid or an alkali to obtain a porous amorphous silicon. The porous amorphous silicon has a lamellar or columnar structure having a mean lamellar diameter or a mean column diameter of 1 nm to 100 nm.

A soft magnetic alloy powder which is a soft magnetic alloy powder having a low coercivity, and with which it is possible to obtain a green compact magnetic core having a high magnetic permeability. A soft magnetic alloy powder including a composition formula (Fe(1−(α+β))X1 αX2 β) (1−(a+b+c+d+e+f)) MaBbPcSidCeSf. XI is one or more elements selected from the group consisting of Co and Ni, X2 is one or more elements selected from the group consisting or Al, Mn, Ag, Zn, Sn, As, Sb, Cu, Cr, Bi, N, O and rare earth elements, and M is one or more elements selected from the group consisting of Nb, Hf, Zr, Ta, Mo, W, Ti and V. The amount of each component contained is within a specified range. The amorphous rate X (%) is at least 85%.