The invention relates to an encapsulated metal particle comprising a core encapsulated in a shell, wherein the core comprises a metallic substance, and wherein the shell comprises a insulating substance. The invention also relates to a polymer composition comprising a plurality of the encapsulated metal particles, a mixture comprising a plurality of encapsulated metal particles and plurality of polymer particles, and the use of the encapsulated metal particle as an additive for increasing the thermal conductivity and/or radio frequency (RF) conductivity of a matrix substance such as an adhesive.

The present invention relates to a low-temperature sinterable copper particle material prepared using an electride and an organic copper compound and a preparation method therefor and, more particularly, to a copper nanoparticle which can be useful as a conductive copper ink material thanks to its small size and high dispersibility, and a method for preparing the copper nanoparticle by reducing an organic copper compound with an electride as a reducing agent. The present invention provides copper nanoparticles which can be suitably used as a conductive copper nanoink material because the copper nanoparticles show the restrained oxidation of the copper, have an average particle diameter of around 5 nm to cause the depression of melting point, are of high dispersibility, and allow the removal of the electride in a simple ultrasonication process. The prepared copper nanoparticles can be useful as an oxidation preventing protector or conductive copper ink material which is small in particle size and high in dispersibility.

A graphene modifying method of metal having following steps of providing metal powders, graphene powders and a binder, the metal powder has metal particles, and the graphene powder has graphene micro pieces, each graphene micro piece is formed by 6-atom unit cells connected with each other, each 6-atom unit cell is connected to a stearic acid functional group by a sp3 bond; mixing the metal powder, the graphene powder, and the binder to generate heat by a friction, each sp3 bond connected with the stearic acid functional group is thereby heated and broken, each 6-atom unit cell is connected with other 6-atom unit cells via the broken sp3 bond, and the metal particles are thereby wrapped by the 6-atom unit cells; and sintering the metal particles into a metal body to transform the plurality of graphene micro pieces into a three-dimensional mash embedded in the metal body.

Disclosed is a method for preparing silver-copper mixed powder having a core-shell structure. The method includes: dissolving silver (Ag) and copper (Cu) in an aqueous nitric acid solution; adding a reducing agent to the solution; and preparing silver-copper mixed powder having a core-shell structure by performing plasma post-treatment, after performing the adding the reducing agent to the solution.

A method is provided for producing a bonding composition containing copper particles and a second liquid medium. In this production method, the copper particles are produced in a first liquid medium using a wet reduction method, and thus a dispersion of the copper particles is prepared. Subsequently, the first liquid medium in the dispersion is ultimately, finally or eventually replaced with the second liquid medium while the dispersion is kept wet. It is also preferable that the first liquid medium is replaced with another liquid medium one or more times, and the second liquid medium is used in the final replacement. The liquid media are preferably replaced at a temperature of lower than 100° C. The second liquid medium preferably includes one or more of water, alcohol, ketone, ester, ether, and hydrocarbon.

A method for fabricating a functionally graded tungsten-copper composite (W—Cu FGC) may include the following steps. A binder alloy powder may be prepared that may include mechanically alloyed metal powders of nickel (Ni), copper (Cu), and manganese (Mn); the binder alloy powder may be mixed with a pure tungsten (W) powder to obtain a modified W powder; a plurality of W—Cu composite powders may be prepared by mixing the modified W powder with pure copper powder with different ratios; the plurality of W—Cu composite powders may then be stacked inside a die; the stacked plurality of W—Cu composite powders may be pressed inside the die to obtain a W—Cu compact; and the W—Cu compact may be sintered to obtain a W—Cu FGC.

A Cu-based sintered sliding member that can be used under high-load conditions. The sliding member is age-hardened, including 5 to 30 mass % Ni, 5 to 20 mass % Sn, 0.1 to 1.2 mass % P, and the rest including Cu and unavoidable impurities. In the sliding member, an alloy phase containing higher concentrations of Ni, P and Sn than their average concentrations in the whole part of the sliding member, is allowed to be present in a grain boundary of a metallic texture, thereby achieving excellent wear resistance. Hence, without needing expensive hard particles, there can be obtained, at low cost, a Cu-based sintered sliding member usable under high-load conditions. Even more excellent wear resistance is achieved by containing 0.3 to 10 mass % of at least one solid lubricant selected from among graphite, graphite fluoride, molybdenum disulfide, tungsten disulfide, boron nitride, calcium fluoride, talc and magnesium silicate mineral powders.

Disclosed is a nano dispersion copper alloy with high air-tightness and low free oxygen content and a brief manufacturing process thereof, wherein alloy comprises the following components: Al.sub.2O.sub.3, Ca and La. The manufacturing process comprises the following steps of: preparing Cu—Al.sub.2O.sub.3 alloy powder by an internal oxidation method; mixing the Cu—Al.sub.2O.sub.3 alloy powder with Cu—Ca—La alloy powder; sheathing the mixed powder under protection of argon; performing hot extrusion and then rotary forging; vacuumizing the sheath after the rotary forging; and sealing and placing the sheath in a nitrogen atmosphere with a temperature of 450° C. to 550° C. and a pressure intensity of 40 Mpa to 60 Mpa for 3 hours to 5 hours. The dispersion copper prepared by the present disclosure has the advantages of low free oxygen content (≤15 ppm), high dimensional stability, good air-tightness and an air leakage rate≤1.0×10.sup.−10 Pa m.sup.3/s after hydrogen annealing.

A sintered friction material comprises a metallic matrix and granular constituents embedded in the matrix. The metallic matrix comprises a copper base alloy. The friction material is characterized in that the granular constituents comprise at least one sintered cemented carbide in a proportion of up to 9 weight percent, based on the total weight of the friction material. Furthermore, a friction body, in particular for clutches and brakes, that comprises a friction lining with at least one layer made of the sintered friction material, and a method for the production of a friction lining with the sintered friction material are described.

The invention relates to a method for producing a part, comprising the production of successive solid metallic layers (201...20n), each layer being produced by depositing a metal (25) called filler metal, said method being characterized in that the part has a specific grain structure.

The invention also relates to a part obtained by means of this method and an alternative method.

The alloy used in the additive manufacturing method of the invention makes it possible to obtain parts with exceptional properties.