Powder particles for forming a homogeneous green body having a sufficient strength and a process for producing a green body by using the powder particles. A green body is shaped by using powder particles of composite particles in which thermoplastic resin particles are scattered on surfaces of large particles in an amount within a predetermined volume ratio range with respect to the large particles, and loaded to form resin pools in contact point peripheral areas of adjoining ones of the large particles and form voids in areas other than the contact point peripheral areas when the thermoplastic resin particles are melted. A green body packed with the powder particles each having a small amount of the thermoplastic resin particles attached thereon is placed under a melting condition of the thermoplastic resin particles, the thermoplastic resin is melted and gathers around contact points (or proximal points) of the adjoining powder particles.

A powder molding method of aluminum and aluminum alloy includes: preparing a feedstock by kneading aluminum powder, aluminum alloy powder, or aluminum composite powder containing a reinforcing material with a thermoplastic organic binder; molding the feedstock to a product having a complex shape via powder injection molding, compression molding, or extrusion molding; and then producing a high-density sintered body having relative density of at least 96% by performing debinding and sintering in a single heating process under an argon gas atmosphere.

A powder molding method of aluminum and aluminum alloy includes: preparing a feedstock by kneading aluminum powder, aluminum alloy powder, or aluminum composite powder containing a reinforcing material with a thermoplastic organic binder; molding the feedstock to a product having a complex shape via powder injection molding, compression molding, or extrusion molding; and then producing a high-density sintered body having relative density of at least 96% by performing debinding and sintering in a single heating process under an argon gas atmosphere.

A preparation method of an electrical contact material includes steps of: adopting chemical plating to cover nickel coating on aquadag or metallic oxide, then covering with silver coating, and forming AgNiC or AgNiMeO core-shell structure, which improves interface wettability of aquadag, metallic oxide and silver matrix, and removes the adverse effect on the electrical contact material mechanical property due to bad interface wettability in conventional powder metallurgy method. What is important is that the silver in intermediate composite particles is replaced by nickel coating, thus reduce the silver use level. The main function of silver coating is to improve inoxidizability of composite particles, sintering granulation property and the deformability during the manufacturing process of intermediate composite particles, thus improve the technological property.

A preparation method of an electrical contact material includes steps of: adopting chemical plating to cover nickel coating on aquadag or metallic oxide, then covering with silver coating, and forming AgNiC or AgNiMeO core-shell structure, which improves interface wettability of aquadag, metallic oxide and silver matrix, and removes the adverse effect on the electrical contact material mechanical property due to bad interface wettability in conventional powder metallurgy method. What is important is that the silver in intermediate composite particles is replaced by nickel coating, thus reduce the silver use level. The main function of silver coating is to improve inoxidizability of composite particles, sintering granulation property and the deformability during the manufacturing process of intermediate composite particles, thus improve the technological property.

According to aspects of the present disclosure, a ternary alloy includes a dual-phase microstructure including a first phase and a second phase. The first phase defines a hexagonal close-packed structure with a stoichiometric ratio of Al.sub.4Fe.sub.1.7Si. The second phase defines a face-centered cubic structure with a stoichiometric ratio of Al.sub.3Fe.sub.2Si. The dual-phase microstructure is stable above about 800 C., and the dual-phase microstructure has a first-phase abundance greater than about 50 parts by weight and a second-phase abundance less than about 50 parts by weight based on 100 parts by weight of the ternary alloy.

According to aspects of the present disclosure, a ternary alloy includes a dual-phase microstructure including a first phase and a second phase. The first phase defines a hexagonal close-packed structure with a stoichiometric ratio of Al.sub.4Fe.sub.1.7Si. The second phase defines a face-centered cubic structure with a stoichiometric ratio of Al.sub.3Fe.sub.2Si. The dual-phase microstructure is stable above about 800 C., and the dual-phase microstructure has a first-phase abundance greater than about 50 parts by weight and a second-phase abundance less than about 50 parts by weight based on 100 parts by weight of the ternary alloy.

An aluminum material for producing light-weight components includes aluminum (Al), scandium (Sc), zirconium (Zr) and ytterbium (Yb), where a weight ratio of scandium (Sc) to zirconium (Zr) to ytterbium (Yb) [Sc/Zr/Yb] is in a range from 10/5/2.5 to 10/2.5/1.25.

An aluminum material for producing light-weight components includes aluminum (Al), scandium (Sc), zirconium (Zr) and ytterbium (Yb), where a weight ratio of scandium (Sc) to zirconium (Zr) to ytterbium (Yb) [Sc/Zr/Yb] is in a range from 10/5/2.5 to 10/2.5/1.25.

A method of preparing a thermoelectric material comprising an iron-sulfur compound, the method including: 1) weighing, grinding, and mixing an iron salt and a sulfur-containing source to obtain a mixed powder; 2) carrying out a hydrothermal reaction with the mixed powder to obtain a black precipitate; 3) washing the precipitate; 4) drying the precipitate under vacuum to obtain FeS.sub.2 powder; 5) annealing the FeS.sub.2 powder under inert atmosphere to obtain annealed powder, where a heating temperature is from 300 C. to 1000 C., a heating time is from 2 hours to 24 hours, and a flow rate of an inert gas is from 30 mL/min to 200 mL/min; and 6) sintering the annealed powder to obtain a thermoelectric material including an iron-sulfur compound.