摘要:
A structure can comprise one or multi-element compound (MEC) nanoparticles. Each MEC nanoparticle can have a plurality of sites comprising one or more elements. Each site can form a compound bond with at least one other site of the MEC nanoparticle. One or more of the compound bonds can comprise a covalent bond, an ionic bond, or a metallic bond. Each MEC nanoparticle can be formed of at least three different elements. For example, one or more MEC nanoparticles can be a multi-element oxide nanoparticle, a multi-element carbide nanoparticle, a multi-element intermetallic nanoparticle, or any other type of compound nanoparticle.
摘要:
Some variations provide a system for producing a functionalized powder, comprising: an agitated pressure vessel; first particles and second particles contained within the agitated pressure vessel; a fluid contained within the agitated pressure vessel; an exhaust line for releasing the fluid from the agitated pressure vessel; and a means for recovering a functionalized powder containing the second particles disposed onto surfaces of the first particles. A preferred fluid is carbon dioxide in liquefied or supercritical form. The carbon dioxide may be initially loaded into the pressure vessel as solid carbon dioxide. The pressure vessel may be batch or continuous and is operated under reaction conditions to functionalize the first particles with the second particles, thereby producing a functionalized powder, such as nanofunctionalized metal particles in which nanoparticles act as grain refiners for a component ultimately produced from the nanofunctionalized metal particles. Methods for making the functionalized powder are also disclosed.
摘要:
Methods disclosed herein include using additive manufacturing to create a joint between a first metallic material and a second metallic material that is different from the first metallic material, wherein the porosity of the joint is less than about 0.1 percent by volume measured according to ASTM B-962. The additive manufacturing can be performed such that no intermetallic brittle phase forms between the first metallic material and the second metallic material.
摘要:
Provided is a nickel-based composite coating, method for producing the same and use thereof. A powder mixture is coated on the surface of a substrate to obtain a nickel-based composite coating, wherein the powder mixture comprises nickel-chromium-boron-silicon powders and barium titanate powders. The barium titanate powders are added to the nickel-based powders as a second phase to form BaTiO3—NiCrBSi metal-based ceramic composite coating. The nickel-based barium titanate composite coating has an excellent damping shock absorbing performance and gives the substrate strength as well. Comparing with the conventional coating materials, the coating obtained by the present disclosure through plasma cladding technique not only bonds with the substrate in a metallurgic way, but also has a small heat affected zone, specifically, an excellent damping shock absorbing performance. In embodiments of the present disclosure, vibration and noise generated by the cylinder head is reduced 20% by using the shock absorbing cladding coating.
摘要:
A carbon-coated metal powder having few impurities, a narrower particle size distribution, and sintering properties is particularly suitable as a conductive powder of a conductive paste for forming internal conductors in a ceramic multilayer electronic component obtained by co-firing multilayered ceramic sheets and internal conductor layers; a conductive paste containing the carbon-coated metal powder; a multilayer electronic component using the conductive paste; and a method for manufacturing the carbon-coated metal powder. The carbon-coated metal powder has specific properties in TMA or ESCA measurements. The carbon-coated metal powder can be obtained by melting and vaporizing a metallic raw material in a reaction vessel, conveying the generated metal vapor into a cooling tube and rapidly cooling the metal vapor by endothermically decomposing a carbon source supplied into the cooling tube, and forming a carbon coating film on metal nuclei surfaces in parallel with generation of the metal nuclei.
摘要:
Methods for millling particles include exposing particles to microwave energy during milling. The methods reduce or eliminate the need for pre- and post-processing of reagents and products while minimizing waste associated with the slow kinetics of heat transfer in traditional resistive heating furnaces. Method of synthesizing particles include providing precursor particles, microwave susceptor media, and milling media in a reaction vessel and simultaneously rotating the reaction vessel while exposing the reaction vessel to microwaves. Apparatus for milling particles include a microwave housing defining a microwave enclosure; a microwave generator configured to generate and direct microwaves to the microwave enclosure; and a rotation shaft within the microwave enclosure, the rotation shaft connected or configured to be connected to a motor for rotation, wherein the rotation shaft is configured to be rotatably coupled, within the microwave enclosure, to a processing vessel.
摘要:
A method for preparing nano-SiO2 reinforced aluminum matrix composites, includes the following: Step-1, powder mixing: mixing aluminum matrix powder with nano-SiO2 powder to obtain raw material powder, wherein the aluminum matrix powder has an average particle size between 30 μm to 100 μm, the nano-SiO2 powder has an average particle size between 5 nm to 145 nm, mass percentage of nano-SiO2 in the raw material powder is 0.01% to 5% and the remaining raw material powder is the aluminum matrix powder; Step-2, shaping: press shaping the powder obtained in the Step-1 to obtain base bodies; Step-3, sintering: sintering the base bodies obtained in the Step-2 in an atmosphere of N2 at 550° C. to 660° C., preserving the temperature for a period of 5 min to 60 min, and cooling in a furnace at end of the period under protection of N2 for 0.5 h to 3 h; and Step-4, heat treatment.
摘要:
A novel silver-coated copper powder, particularly a silver-coated copper powder particle having a dendritic shape, having increased electrical conductivity with no need to increase the silver content is provided. The silver-coated copper powder is composed of a silver-coated copper particle coated with a silver layer containing silver or a silver alloy, including a silver-coated copper particle having a dendritic shape, containing nitrogen (N) in the silver layer, and having a nitrogen (N) content of 0.2 to 10.0 parts by mass with respect to 100 parts by mass of the silver content.
摘要:
A novel class of reagents, useful for synthesis of elemental nanoparticles, includes at least one element, formally in oxidation state zero in complex with a hydride molecule. The reagents can optionally include an additional ligand incorporated into the complex. Elemental nanoparticles are synthesized by adding solvent to the reagent, optionally with a free ligand and/or a monoatomic cation.
摘要:
This invention aims at providing a carbon-coated metal powder having few impurities, a narrower particle size distribution, and sintering properties particularly suitable as a conductive powder of a conductive paste for forming internal conductors in a ceramic multilayer electronic component obtained by co-firing multilayered ceramic sheets and internal conductor layers; a conductive paste containing the carbon-coated metal powder; a multilayer electronic component using the conductive paste; and a method for manufacturing the carbon-coated metal powder. The carbon-coated metal powder has specific properties in TMA or ESCA measurements. The carbon-coated metal powder can be obtained by melting and vaporizing a metallic raw material in a reaction vessel, conveying the generated metal vapor into a cooling tube and rapidly cooling the metal vapor by endothermically decomposing a carbon source supplied into the cooling tube, and forming a carbon coating film on metal nuclei surfaces in parallel with generation of the metal nuclei.