Provided is a group of rare-earth regenerator material particles having an average particle size of 0.01 to 3 mm, wherein the proportion of particles having a ratio of a long diameter to a short diameter of 2 or less is 90% or more by number, and the proportion of particles having a depressed portion having a length of 1/10 to of a circumferential length on a particle surface is 30% or more by number. By forming the depressed portion on the surface of the regenerator material particles, it is possible to increase permeability of an operating medium gas and a contact surface area with the operating medium gas.

An improved method of manufacturing a cast part by sand casting, permanent mold casting, investment casting, lost foam casting, die casting, or centrifugal casting, or a powder metal material by water, gas, plasma, ultrasonic, or rotating disk atomization is provided. The method includes adding at least one additive to a melted metal material before or during the casting or atomization process. The at least one additive forms a protective gas atmosphere surrounding the melted metal material which is at least three times greater than the volume of melt to be treated. The protective atmosphere prevents introduction or re-introduction of contaminants, such as sulfur (S) and oxygen (O.sub.2), into the material. The cast parts or atomized particles produced include at least one of the following advantages: less internal pores, less internal oxides, median circularity of at least 0.60, median roundness of at least 0.60 and increased sphericity of microstructural phases and/or constituents.

A titanium alloy additive manufacturing product contains 5.50 to 6.75 wt % of Al, 3.50 to 4.50 wt % of V, 0.20 wt % or less of O, 0.40 wt % or less of Fe, 0.015 wt % or less of H, 0.08 wt % or less of C, 0.05 wt % or less of N, and inevitable impurities, in which a pore content is 0.05 number/mm.sup.2 or less, and a tensile strength is 855 MPa or more.

A titanium alloy additive manufacturing product contains 5.50 to 6.75 wt % of Al, 3.50 to 4.50 wt % of V, 0.20 wt % or less of O, 0.40 wt % or less of Fe, 0.015 wt % or less of H, 0.08 wt % or less of C, 0.05 wt % or less of N, and inevitable impurities, in which a pore content is 0.05 number/mm.sup.2 or less, and a tensile strength is 855 MPa or more.

A titanium alloy additive manufacturing product contains 5.50 to 6.75 wt % of Al, 3.50 to 4.50 wt % of V, 0.20 wt % or less of O, 0.40 wt % or less of Fe, 0.015 wt % or less of H, 0.08 wt % or less of C, 0.05 wt % or less of N, and inevitable impurities, in which a pore content is 0.05 number/mm.sup.2 or less, and a tensile strength is 855 MPa or more.

A method for producing a water-atomized metal powder, comprising applying water to a molten metal stream, dividing the molten metal stream into a metal powder, and cooling the metal powder, wherein the metal powder is further subjected to secondary cooling with cooling capacity having a minimum heat flux point (MHF point) higher than the surface temperature of the metal powder in addition to the cooling and the secondary cooling is performed from a temperature range where the temperature of the metal powder after the cooling is not lower than the cooling start temperature necessary for amorphization nor higher than the minimum heat flux point (MHF point).

A process for applying a low coefficient of friction coating to interacting parts of a mechanical device. The low coefficient coating is comprised of nanoparticles of a metal melting below about 400 C., preferably bismuth. Interacting parts of a mechanical device, prior to assembly of the mechanical device, are submerged in a dispersion of the nanoparticles, then heated to an effective temperature, then cooled, thereby resulting in a coating of the nanoparticles onto the interacting parts.

A process for applying a low coefficient of friction coating to interacting parts of a mechanical device. The low coefficient coating is comprised of nanoparticles of a metal melting below about 400 C., preferably bismuth. Interacting parts of a mechanical device, prior to assembly of the mechanical device, are submerged in a dispersion of the nanoparticles, then heated to an effective temperature, then cooled, thereby resulting in a coating of the nanoparticles onto the interacting parts.

Provided is a flaky soft magnetic powder including an FeSiAl alloy having an oxygen content of 0.6 mass % or less, a manganese content of 0.1 mass % to 1.0 mass %, and the balance incidental impurities. The flaky soft magnetic powder has an average particle size of 43 to 60 m and exhibits a coercive force Hc of 106 A/m or less as measured under application of a magnetic field in an in-plane direction of the flaky soft magnetic powder. The ratio of the tap density to the true density of the flaky soft magnetic powder is 0.17 or less. Also provided is a method of producing the flaky soft magnetic powder. The use of the flaky soft magnetic powder can produce a magnetic sheet having particularly high magnetic permeability.

Provided is a flaky soft magnetic powder including an FeSiAl alloy having an oxygen content of 0.6 mass % or less, a manganese content of 0.1 mass % to 1.0 mass %, and the balance incidental impurities. The flaky soft magnetic powder has an average particle size of 43 to 60 m and exhibits a coercive force Hc of 106 A/m or less as measured under application of a magnetic field in an in-plane direction of the flaky soft magnetic powder. The ratio of the tap density to the true density of the flaky soft magnetic powder is 0.17 or less. Also provided is a method of producing the flaky soft magnetic powder. The use of the flaky soft magnetic powder can produce a magnetic sheet having particularly high magnetic permeability.