A method for preparing a rare earth aluminum alloy powder applicable for additive manufacturing includes: heating and melting aluminum ingots into an aluminum melt; adding required alloy elements to the aluminum melt to obtain an alloy melt in which the alloy elements are present in the following preset percentages by weight: 1.00% to 10.00% of Ce, 0.05% to 8.00% of Mg, 0.10% to 7.50% of Y, 0.10% to 2.50% of Zr, less than 0.1% of impurities, and the balance aluminum; leading out the alloy melt through a fluid guiding pipe, and impacting the alloy melt with a high-pressure gas flow so that the alloy melt is atomized into fine droplets under an action of surface tension, and solidified into spherical alloy powder; and collecting the spherical alloy powder in a vacuum collector, and screening and drying the spherical alloy powder to obtain the rare earth aluminum alloy powder.

A method, and systems in which such method may be practiced, allow for the separation of elemental metals from metal alloy. A metal alloy is atomized to form metal alloy particulates. The metal alloy particulates are exposed to an oxidizing agent, such as chlorine gas in the presence of a salt, such as NaCl, an acid, such as HCl, and water. The resulting solution may be filtered to remove particulates, reduced, filtered, reduced, filtered, and so on. In aspects, the method is used to refine gold alloy by oxidation of elemental sponge gold to gold chloride followed by reduction to pure elemental gold.

A method, and systems in which such method may be practiced, allow for the separation of elemental metals from metal alloy. A metal alloy is atomized to form metal alloy particulates. The metal alloy particulates are exposed to an oxidizing agent, such as chlorine gas in the presence of a salt, such as NaCl, an acid, such as HCl, and water. The resulting solution may be filtered to remove particulates, reduced, filtered, reduced, filtered, and so on. In aspects, the method is used to refine gold alloy by oxidation of elemental sponge gold to gold chloride followed by reduction to pure elemental gold.

A method for manufacturing metal powder is provided. The method includes preparing first metal powder, agglomerating the first metal powder to manufacture second metal powder in which the first metal powder is agglomerated, coating the second metal powder with an organic binder, and agglomerating and coarsening the second metal powder coated with the organic binder to manufacture third metal powder having higher flowability than the second metal powder coated with the organic binder.

A method for manufacturing metal powder is provided. The method includes preparing first metal powder, agglomerating the first metal powder to manufacture second metal powder in which the first metal powder is agglomerated, coating the second metal powder with an organic binder, and agglomerating and coarsening the second metal powder coated with the organic binder to manufacture third metal powder having higher flowability than the second metal powder coated with the organic binder.

An alloy treatment method is provided, in which a solution containing nickel and/or cobalt is obtained from an alloy containing nickel and/or cobalt and also containing copper and zinc, the method comprising: a leaching step for subjecting the alloy to a leaching treatment with an acid under the condition where a sulfating agent is present to produce a leachate; a reduction step for subjecting the leachate to a reduction treatment using a reducing agent to produce a reduced solution; an oxidation/neutralization step for adding an oxidizing agent and a neutralizing agent to the reduced solution to produce a neutralized solution containing nickel and/or cobalt and also containing zinc; and a solvent extraction step for subjecting the neutralized solution to a solvent extraction procedure using an acidic phosphorus compound-based extractant to produce a solution containing nickel and/or cobalt.

An alloy treatment method is provided, in which a solution containing nickel and/or cobalt is obtained from an alloy containing nickel and/or cobalt and also containing copper and zinc, the method comprising: a leaching step for subjecting the alloy to a leaching treatment with an acid under the condition where a sulfating agent is present to produce a leachate; a reduction step for subjecting the leachate to a reduction treatment using a reducing agent to produce a reduced solution; an oxidation/neutralization step for adding an oxidizing agent and a neutralizing agent to the reduced solution to produce a neutralized solution containing nickel and/or cobalt and also containing zinc; and a solvent extraction step for subjecting the neutralized solution to a solvent extraction procedure using an acidic phosphorus compound-based extractant to produce a solution containing nickel and/or cobalt.

A device for granulating powders by cryogenic atomisation, characterised in that it comprises: a device for mixing powders by cryogenic fluid, comprising at least one chamber for mixing powders, comprising a cryogenic fluid; and a device for atomising a suspension of powders mixed by the device for mixing powders in order to allow a granulation of the powders, comprising a way of fractionating the suspension of powders making it possible to adjust the size of the droplets of powders to be atomised, and a method for adjusting the moisture of the mixed powders and/or the moisture of the atomisation atmosphere.

A printed metallic part is provided. The alloy has the composition of Fe at 69.2 wt. % to 89.1 wt. %; Cr at 7.25 wt. % to 16.0 wt. %; Nb at 0.01 wt. % to 10.0 wt. %; Mo at 0.5 wt. % to 4.0 wt. %. C at 0.03 wt. % to 0.4 wt. % and optionally one or more of Ni, Cu, Si, W, Mn, N and B. The printed metallic part has a tensile strength of at least 1300 MPa, a yield strength of at least 700 MPa, an elongation of at least 4.0%, and a hardness of at least 45 HRC.

Active metal particles in which the surface layer is hardly oxidized and a method for producing the active metal particles is provided. In the method for modifying the surface of active metal particles, heat is generated by moving active metal powder in a fluid, and the surface layer of the active metal particles is reacted with an arbitrary component in the fluid by the heat to modify the surface layer. Preferably, moving the active metal powder draws a substantially circular orbit while vibrating. A vibrating mill is preferably used when making such movement with respect to the active metal powder. Then, the powder obtained by the surface modification has a nitrogen-containing coating as a surface layer with a thickness more than 1 nm and less than or equal to 6 nm. The powder has a fluidity in the range of 25 seconds/50 g or more and 45 seconds/50 g or less.