Polycrystalline magnesium silicide containing only carbon as a dopant and having carbon distributed at the crystal grain boundaries and within the crystal grains, a thermoelectric conversion material obtained using the polycrystalline magnesium silicide, a sintered compact, a thermoelectric conversion element, and a thermoelectric conversion module, and methods for producing polycrystalline magnesium silicide and a sintered compact.

Polycrystalline magnesium silicide containing only carbon as a dopant and having carbon distributed at the crystal grain boundaries and within the crystal grains, a thermoelectric conversion material obtained using the polycrystalline magnesium silicide, a sintered compact, a thermoelectric conversion element, and a thermoelectric conversion module, and methods for producing polycrystalline magnesium silicide and a sintered compact.

Some variations provide a method of making an additively manufactured metal component, comprising: providing a feedstock that includes a high-vapor-pressure metal; exposing a first amount of the feedstock to an energy source for melting; and solidifying the melt layer, thereby generating a solid layer of an additively manufactured metal component. The metal-containing feedstock is enriched with a higher concentration of the high-vapor-pressure metal compared to its concentration in the additively manufactured metal component. The high-vapor-pressure metal may be selected from Mg, Zn, Li, Al, Cd, Hg, K, Na, Rb, Cs, Mn, Be, Ca, Sr, or Ba, for example. Additively manufactured metal components are provided. Metal-containing feedstocks for additive manufacturing are also disclosed, wherein concentration of at least one high-vapor-pressure metal in the feedstock is selected based on a desired concentration of the high-vapor-pressure metal in an additively manufactured metal component derived from the metal-containing feedstock. Various feedstock compositions are disclosed.

Morphology, microstructure, compressive behavior, and biocorrosive properties of magnesium or magnesium alloy foams allow for their use in biodegradable biomedical, metal-air battery electrode, hydrogen storage, and lightweight transportation applications. Magnesium or Mg alloy foams are usually very difficult to manufacture due to the strong oxidation layer around the metallic particles; however, in this invention, they can be synthesized via a camphene-based freeze-casting process with the addition of graphite powder using precisely controlled heat-treatment parameters. The average porosity ranges from 45 to 85 percent and the median pore diameter is about a few tens to hundreds of microns, which are suitable for bio and energy applications utilizing their enhanced surface area. This invention based on powder-slurry freeze-casting method using camphene as a volatile solvent is also applicable for other metal foams such as iron, copper, or others to produce three-dimensional metal foams with high strut connectivity.

The present invention discloses a method for chemically marking metal products such as metal ingots and other rough or processed metal materials. More specifically, the aim of the present invention is the use of tracers during the method for casting or other methods for manufacturing metal products. These tracers in turn can be identified by physico-chemical methods for confirming the specification of the product, the source of the products or of other similar elements and to assist anti-counterfeiting measures or the identification of production batches or cycles.

The present invention discloses a method for chemically marking metal products such as metal ingots and other rough or processed metal materials. More specifically, the aim of the present invention is the use of tracers during the method for casting or other methods for manufacturing metal products. These tracers in turn can be identified by physico-chemical methods for confirming the specification of the product, the source of the products or of other similar elements and to assist anti-counterfeiting measures or the identification of production batches or cycles.

According to one embodiment of the present invention, a cast alloy material is provided. The cast alloy material includes a matrix metal and an alloy element, wherein oxide particles in a nanometer scale are decomposed in the matrix metal, so that a new phase including a metal element that is a component of the oxide particles and the alloy element forms a band or network structure, wherein the metal element and the alloy element have a relationship of a negative heat of mixing, and wherein oxygen atoms formed by decomposition of the oxide particles are dispersed in the matrix metal and do not form an oxide with the matrix metal.

According to one embodiment of the present invention, a cast alloy material is provided. The cast alloy material includes a matrix metal and an alloy element, wherein oxide particles in a nanometer scale are decomposed in the matrix metal, so that a new phase including a metal element that is a component of the oxide particles and the alloy element forms a band or network structure, wherein the metal element and the alloy element have a relationship of a negative heat of mixing, and wherein oxygen atoms formed by decomposition of the oxide particles are dispersed in the matrix metal and do not form an oxide with the matrix metal.

A powder metal compact is disclosed. The powder metal compact includes a cellular nanomatrix comprising a nanomatrix material. The powder metal compact also includes a plurality of dispersed particles comprising a particle core material that comprises an Al—Cu—Mg, Al—Mn, Al—Si, Al—Mg, Al—Mg—Si, Al—Zn, Al—Zn—Cu, Al—Zn—Mg, Al—Zn—Cr, Al—Zn—Zr, or Al—Sn—Li alloy, or a combination thereof, dispersed in the cellular nanomatrix.

Disclosed herein is an article comprising a metal alloy; where the metal alloy comprises a base metal, a second element and a third element; where the base metal is magnesium, calcium, strontium, zinc, or a combination thereof; where the second element is chemically different from the third element; and where the second element and the third element are scandium, yttrium, gadolium, cerium, neodymium, dysporium, or a combination thereof; and a protective layer disposed upon the metal alloy and is reactively bonded to the metal alloy; where the protective layer comprises a base non-metallic derivative, a second non-metallic derivative and a third non-metallic derivative of metals present in the metal alloy; and where the base non-metallic derivative, the second non-metallic derivative and the third non-metallic derivative are all chemically different from one another.