The purpose of the present invention is to provide a method for causing sufficient deformation in precursor particles even when a soft high-purity metal is used for an outer layer material in mechanical milling, and manufacturing an MgB.sub.2 superconducting wire. A method for manufacturing an MgB.sub.2 superconducting wire in which an MgB.sub.2 filament is covered by an outer layer material, the method comprising: subjecting magnesium powder and boron powder to a shock that is insufficient for MgB.sub.2 to be clearly produced, and producing precursor particles in which boron particles are dispersed inside a magnesium matrix; filling a metal tub with the precursor particles; processing the metal tube filled with precursor particles to form a wire; and heat-treating the wire to synthesize the MgB.sub.2; wherein the method is characterized in that a portion of the wire-drawing step includes swaging.

At a diameter-decreasing operation during manufacture of a poppet valve, an intermediate stem portion at which a valve head portion and an intermediate stem portion are made integral by way of a neck portion may be inserted between/among diameter-decreasing tools. Application of compressive forces from compressing surfaces of the diameter-decreasing tools may cause a part of the intermediate stem portion to be decreased in diameter and may cause a main body portion of a first stem portion to be formed and may cause formation of a stepped portion which is continuous with the main body portion, and formation, by an absence of decrease in diameter, of a second stem portion which is broader in girth than the main body portion and which is continuous with the neck portion and which is also continuous with the main body portion by way of the stepped portion.

A method for producing a shaft, which is at least partially not circular in cross-section, from a substantially cylindrical blank by means of radial forging, wherein the blank is not rotated in a final radial forging process.

A method for producing a shaft, which is at least partially not circular in cross-section, from a substantially cylindrical blank by means of radial forging, wherein the blank is not rotated in a final radial forging process.

A method of manufacturing an aerosol generation system heater element is described. The aerosol generation system heater element comprising a seamless hollow tube, and the method comprises deforming a wall of a hollow tube to form the seamless hollow tube, the seamless hollow tube having a deformed wall, wherein the deformed wall of the seamless hollow tube is thinner than the wall of the hollow tube.

This hollow shaft member 10 includes paired diameter-reduced sections 11 respectively formed at both shaft ends of a hollow shaft-like tubular material by performing swaging processing on both the shaft ends, and an intermediate section 12 located between the paired diameter-reduced sections, and having an outer diameter larger than an outer diameter of the paired diameter-reduced sections. Shapes of connection boundaries between the intermediate section 12 and the diameter-reduced sections 11 are formed as perpendicular step-shaped sections 13 stepped substantially perpendicular to an axial direction, and the perpendicular step-shaped sections 13 are formed by the swaging processing. With such a configuration, a hollow shaft member for a rolling device in which a weight reduction has been achieved can be provided.

A method for producing a shaft, which is at least partially not circular in cross-section, from a substantially cylindrical blank by means of radial forging, wherein the blank is not rotated in a final radial forging process.

A method for producing a shaft, which is at least partially not circular in cross-section, from a substantially cylindrical blank by means of radial forging, wherein the blank is not rotated in a final radial forging process.

A metallic material manufactured by a method including steps of (1) subjecting a semifinished metallic billet having at least one of a nanocrystalline microstructure and an ultrafine-grained microstructure to a rotary incremental forming process to form an intermediate wrought metallic billet and (2) subjecting the intermediate wrought metallic billet to a high rate forming process, wherein the high rate forming process includes a high rate forming process average equivalent strain rate, the high rate forming process average equivalent strain rate being at least about 0.1 s−1.

A metallic material manufactured by a method including steps of (1) subjecting a semifinished metallic billet having at least one of a nanocrystalline microstructure and an ultrafine-grained microstructure to a rotary incremental forming process to form an intermediate wrought metallic billet and (2) subjecting the intermediate wrought metallic billet to a high rate forming process, wherein the high rate forming process includes a high rate forming process average equivalent strain rate, the high rate forming process average equivalent strain rate being at least about 0.1 s−1.