The invention relates to a method for coding metal powder. Said method comprises the following steps: providing a melt, forming a melt stream, spraying the melt stream by means of a spraying fluid, and forming metal powder particles from the melt stream. The method is characterized in that, during the spraying of the melt and/or the spraying fluid, a coding component or a coding gas is added in such a way that the use of the coding component in the metal powder can be detected, wherein the gaseous coding component comprises one or more isotopes of at least one gas and the fraction of the at least one isotope is changed in comparison with the naturally occurring fraction of said isotope in the gas and/or wherein the gaseous coding component contains gaseous alloying elements.

A method for gas atomization of a titanium alloy, nickel alloy, or other alumina (Al.sub.2O.sub.3) forming alloy wherein the atomized particles are exposed as they solidify and cool in a very short time to multiple gaseous reactive agents for the in-situ formation of a passivation reaction film on the atomized particles wherein the reaction film retains a precursor halogen alloying element that is subsequently introduced into a microstructure formed by subsequent thermally processing of the atomized particles to improve oxidation resistance.

Provided is a soft magnetic alloy which has high saturation flux density, low coercivity, and a high specific resistance, and is represented by the compositional formula (Fe.sub.(1(+))X1.sub.X2.sub.).sub.(1(a+b+c+d+e))M.sub.aSi.sub.bCu.sub.cX3.sub.dB.sub.e, wherein X1 is at least one element selected from the group consisting of Co and Ni, X2 is at least one element selected from the group consisting of Ti, V, Mn, Ag, Zn, Al, Sn, As, Sb, Bi, and rare earth elements, X3 is at least one element selected from the group consisting of C and Ge, and M is at least one element selected from the group consisting of Zr, Nb, Hf, Ta, Mo, and W, and wherein 0.030a0.120, 0.020b0.175, 0c0.020, 0d0.100, 0e0.030, 0, 0, and 0+0.55).

A method and apparatus for fabrication of objects retaining nano-scale characteristics. A composition is provided comprising grain growth inhibitor particles in solution with a binding agent in a molten phase. An electric field and a magnetic field are generated with a combined extraction electrode. The composition is electrosprayed from a nozzle with the electric field to form a stream of droplets. The electric field drives the droplets toward a moving stage holding an object comprising successive deposition layers. The magnetic field limits dispersion of the stream of droplets. The stage is moved laterally as the stream of droplets impacts the object to form a current deposition layer of the object. The stage is moved vertically as necessary to maintain a target stand-off distance between the nozzle and a previous deposition layer of the object, based on profile data of the previous deposition layer.

Provided is a method of preparing an alloy powder, comprising the steps of: melting the metal elements to produce the alloy solution; atomizing the alloy solution into small drops under oxygen-containing atmosphere; forcing the small drops to be quickly cooled under the driving of the atomizing flow to obtain the alloy powder; wherein, when the method is used to prepare CuInGa alloy powder, Cu/(In+Ga) is 0.5 to 1.1, In/(In+Ga) is 0.2 to 0.9, Ga/(In+Ga) is 0.1 to 0.8, In/(In+Ga)+Ga/(In+Ga) is 1. Also provided is an alloy powder and a method of preparing CuInGa alloy powder.

A method for gas atomization of oxygen-reactive reactive metals and alloys wherein the atomized particles are exposed as they solidify and cool in a very short time to multiple gaseous reactive agents for the in-situ formation of a protective reaction film on the atomized particles. The present invention is especially useful for making highly pyrophoric reactive metal or alloy atomized powders, such as atomized magnesium and magnesium alloy powders. The gaseous reactive species (agents) are introduced into the atomization spray chamber at locations downstream of a gas atomizing nozzle as determined by the desired powder or particle temperature for the reactions and the desired thickness of the reaction film.

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.

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 method for gas atomization of a titanium alloy, nickel alloy, or other alumina (Al.sub.2O.sub.3)-forming alloy wherein the atomized particles are exposed as they solidify and cool in a very short time to multiple gaseous reactive agents for the in-situ formation of a passivation reaction film on the atomized particles wherein the reaction film retains a precursor halogen alloying element that is subsequently introduced into a microstructure formed by subsequent thermally processing of the atomized particles to improve oxidation resistance.

A method for gas atomization of oxygen-reactive reactive metals and alloys wherein the atomized particles are exposed as they solidify and cool in a very short time to multiple gaseous reactive agents for the in-situ formation of a protective reaction film on the atomized particles. The present invention is especially useful for making highly pyrophoric reactive metal or alloy atomized powders, such as atomized magnesium and magnesium alloy powders. The gaseous reactive species (agents) are introduced into the atomization spray chamber at locations downstream of a gas atomizing nozzle as determined by the desired powder or particle temperature for the reactions and the desired thickness of the reaction film.