A graphite-copper composite material that includes a copper layer having an average thickness of 15 μm or less and scaly graphite particles laminated with the copper layer interposed therebetween. The graphite-copper composite material has a copper volume fraction of 3 to 20%. The graphite-copper composite material further has: (A) copper crystal grains of the copper layer having an average grain size of 2.8 μm or less, a mass fraction of Al of less than 0.02%, and a mass fraction of Si of less than 0.04%, or (B) an interfacial gap of the copper layer and the scaly graphite particles of 150 nm or less.

One object of the present invention is to provide a bonding material capable of forming a highly reliable bond, the present invention provides a bonding material having a plate shape or a sheet shape, wherein the bonding material includes: fine copper particles having an average particle diameter of 300 nm or less; coarse copper particles having an average particle diameter of 3 .Math.m or more and 11 .Math.m or less; and a reducing agent which reduces the fine copper particles and the coarse copper particles.

The present invention discloses a method for refining large-particle-size pure copper or copper alloy particles by high-energy ball milling, the method comprising the following steps: (1) using large-particle-size pure copper or copper alloy coarse particles as a raw material and cyclohexane or water as a process control agent, and crushing and refining the particles by high-energy ball milling to obtain small-particle-size copper or copper alloy powder; and (2) decreasing an oxygen content in the powder obtained in step (1) in a reducing atmosphere to obtain pure copper or copper alloy powder. In the present invention, by improving the overall process flow of the preparation method and the parameter conditions of each process step, the method greatly decreases energy consumption compared with existing copper powder preparation techniques. In addition, the method features a simple process and low production costs.

A sintered bearing 1 is formed by sintering a raw material powder containing aluminum fluoride. The sintered bearing 1 has a structure obtained by sintering an aluminum-copper alloy and contains 3 to 13 mass % aluminum and 0.05 to 0.6 mass % phosphorus, copper as a main component of the remainder, and inevitable impurities. The sintered bearing 1 is manufactured by performing sintering in a closed space 23, and by, under the assumption that all aluminum fluoride contained in the raw material powder is gasified in the closed space 23, controlling the concentration of the aluminum fluoride gas to be 5 ppm or more, thus performing the sintering.

Provided is a Cu-based alloy powder that is suitable for a process involving rapid melting and rapid solidification and that can provide a shaped object superior in characteristics. The powder is composed of a Cu-based alloy, which contains an element M being one or more elements selected from Cr, Fe, Ni, Zr, and Nb: 0.1% by mass or more and 10.0% by mass or less, Si: more than 0% by mass and 0.20% by mass or less, P: more than 0% by mass and 0.10% by mass or less, and S: more than 0% by mass and 0.10% by mass or less, the balance being Cu and inevitable impurities. This powder has a ratio (D50/TD) of the average particle diameter D50 (μm) thereof to the tap density TD (Mg/m.sup.3) is 0.2×10.sup.−5.Math.m.sup.4/Mg or more and 20×10.sup.−5.Math.m.sup.4/Mg or less, and has a sphericity of 0.80 or more and 0.95 or less.

A conductive supporting member includes an outer portion that includes a Cu matrix phase and a second phase dispersed in the Cu matrix phase and containing a Cu—Zr compound and that has an alloy composition represented by Cu-xZr (x is atomic % of Zr and 0.5≤x≤16.7 is satisfied) and an inner portion that is present on an inner side of the outer portion, is formed of a metal containing Cu, and has higher conductivity than the outer portion.

There are provided high melting point metal or alloy powder atomization manufacturing processes comprising providing a melt of the high melting point metal or alloy through a feed tube; diverting the melt at a diverting angle with respect to a central axis of the feed tube to obtain a diverted melt; directing the diverted melt to an atomization area; and providing at least one atomization gas stream to the atomization area. The atomization process can be carried out in the presence of water within an atomization chamber used for the atomization process.

A process for forming extruded products using a device having a scroll face configured to apply a rotational shearing force and an axial extrusion force to the same preselected location on material wherein a combination of the rotational shearing force and the axial extrusion force upon the same location cause a portion of the material to plasticize, flow and recombine in desired configurations. This process provides for a significant number of advantages and industrial applications, including but not limited to extruding tubes used for vehicle components with 50 to 100 percent greater ductility and energy absorption over conventional extrusion technologies, while dramatically reducing manufacturing costs.

A method of surface modification of a metal or metal alloy powder includes the steps of providing a metal or metal alloy powder including copper, gold, or silver and having an average diameter in the micron range; providing a powder having an alloying element to form an alloying element powder. The alloying element powder particles have an average diameter less than 10 micron and no more than half the average diameter of the metal or metal alloy powder particles; mixing the powders to form a mixed powder; heating the mixed powder in an atmosphere of reducing gas to a first temperature T1; after temperature T1 is reached, replacing the reducing gas atmosphere with an inert gas atmosphere and maintaining the temperature at a second temperature T2 for a predetermined time. The alloying element is capable of diffusing in the metal or metal alloy element at temperature T2.

A preparation method for a W—Cu composite plate with a Cu phase in finger-shaped gradient distribution is provided. The method includes adding WO.sub.X powder obtained with ammonium metatungstate as a raw material into W powder through a combustion synthesis method, adding a binder and a pore-forming agent to prepare a slurry, then performing tape casting, soaking in water and sintering to obtain a W framework with pores in finger-shaped distribution, and then infiltrating Cu to obtain a target product. The Cu phase in the W—Cu composite material prepared by the present method is distributed in a finger-shaped gradient manner from an infiltration surface to the interior of a specimen, the Cu phase and the W phase are mutually pinned, and the W—Cu interface has good bonding strength. The present method has the characteristics of adjustable material component performance, simple process, low cost, suitability for large-scale production and the like.