Provided is a silver powder which has an appropriate viscosity range at the time of paste production, can be easily kneaded, and prevents the occurrence of flakes. The silver powder to be used has a specific surface area ratio SA.sub.B/SA.sub.S of 0.5 to 0.9, wherein SA.sub.B is a specific surface area measured by the BET method, and SA.sub.S is a specific surface area calculated from a mean primary-particle diameter D.sub.S measured with a scanning electron microscope. Furthermore, the silver powder preferably has a degree of aggregation of 1.5 to 5.0, the degree being obtained in such a manner that a volume median diameter D.sub.50 measured by laser diffraction scattering is divided by the foregoing Ds.

A method for producing a metal particle which includes the steps of: mixing a metal salt and a polycarboxylic acid in a liquid phase; adding a reducing agent to the resultant mixture to deposit metal particles; and drying the deposited metal particles.

A method for producing a metal particle which includes the steps of: mixing a metal salt and a polycarboxylic acid in a liquid phase; adding a reducing agent to the resultant mixture to deposit metal particles; and drying the deposited metal particles.

Provided in one embodiment is a method of identifying a stable phase of an ordering binary alloy system comprising a solute element and a solvent element, the method comprising: determining at least three thermodynamic parameters associated with grain boundary segregation, phase separation, and intermetallic compound formation of the ordering binary alloy system; and identifying the stable phase of the ordering binary alloy system based on the first thermodynamic parameter, the second thermodynamic parameter and the third thermodynamic parameter by comparing the first thermodynamic parameter, the second thermodynamic parameter and the third thermodynamic parameter with a predetermined set of respective thermodynamic parameters to identify the stable phase; wherein the stable phase is one of a stable nanocrystalline phase, a metastable nanocrystalline phase, and a non-nanocrystalline phase.

Provided in one embodiment is a method of identifying a stable phase of an ordering binary alloy system comprising a solute element and a solvent element, the method comprising: determining at least three thermodynamic parameters associated with grain boundary segregation, phase separation, and intermetallic compound formation of the ordering binary alloy system; and identifying the stable phase of the ordering binary alloy system based on the first thermodynamic parameter, the second thermodynamic parameter and the third thermodynamic parameter by comparing the first thermodynamic parameter, the second thermodynamic parameter and the third thermodynamic parameter with a predetermined set of respective thermodynamic parameters to identify the stable phase; wherein the stable phase is one of a stable nanocrystalline phase, a metastable nanocrystalline phase, and a non-nanocrystalline phase.

The present invention addresses the problem of providing a method for producing metal microparticles in which the particle diameter and the coefficient of variation are controlled. Using at least two kinds of fluid to be processed including a fluid which contains at least one kind of reducing agent, the fluid to be processed is mixed in a thin film fluid formed between at least two processing surfaces, at least one of which rotates relative to the other, and which are disposed facing each other and capable of approaching and separating from each other, and metalmicroparticles are separated. At this time, the fluid to be processed containing one or both of the fluid which contains at least one kind of metal and/or metal compound and the fluid which contains at least one kind of reducing agent contains a water-containing polyol in which water and a polyol are mixed, and does not contain a monovalent alcohol, and the particle diameter and coefficient of variance of the separated metal microparticles is controlled by controlling the ratio of water contained in the water-containing polyol.

A composite member includes: a substrate formed of a composite material containing a plurality of diamond grains and a metal phase; and a coating layer made of metal. The surface of the substrate includes a surface of the metal phase, and a protrusion formed of a part of at least one diamond grain of the diamond grains and protruding from the surface of the metal phase. In a plan view, the coating layer includes a metal coating portion, and a grain coating portion. A ratio of a thickness of the grain coating portion to a thickness of the metal coating portion is equal to or less than 0.80. The coating layer has a surface roughness as an arithmetic mean roughness Ra of less than 2.0 μm.

A composite member includes: a substrate formed of a composite material containing a plurality of diamond grains and a metal phase; and a coating layer made of metal. The surface of the substrate includes a surface of the metal phase, and a protrusion formed of a part of at least one diamond grain of the diamond grains and protruding from the surface of the metal phase. In a plan view, the coating layer includes a metal coating portion, and a grain coating portion. A ratio of a thickness of the grain coating portion to a thickness of the metal coating portion is equal to or less than 0.80. The coating layer has a surface roughness as an arithmetic mean roughness Ra of less than 2.0 μm.

A method of making dispersion-strengthened alloy particles involves melting an alloy having a corrosion and/or oxidation resistance-imparting alloying element, a dispersoid-forming element, and a matrix metal wherein the dispersoid-forming element exhibits a greater tendency to react with a reactive species acquired from an atomizing gas than does the alloying element. The melted alloy is atomized with the atomizing gas including the reactive species to form atomized particles so that the reactive species is (a) dissolved in solid solution to a depth below the surface of atomized particles and/or (b) reacted with the dispersoid-forming element to form dispersoids in the atomized particles to a depth below the surface of said atomized particles. The atomized alloy particles are solidified as solidified alloy particles or as a solidified deposit of alloy particles. Bodies made from the dispersion strengthened alloy particles, deposit thereof, exhibit enhanced fatigue and creep resistance and reduced wear as well as enhanced corrosion and/or oxidation resistance at high temperatures by virtue of the presence of the corrosion and/or oxidation resistance imparting alloying element in solid solution in the particle alloy matrix.

A method of making dispersion-strengthened alloy particles involves melting an alloy having a corrosion and/or oxidation resistance-imparting alloying element, a dispersoid-forming element, and a matrix metal wherein the dispersoid-forming element exhibits a greater tendency to react with a reactive species acquired from an atomizing gas than does the alloying element. The melted alloy is atomized with the atomizing gas including the reactive species to form atomized particles so that the reactive species is (a) dissolved in solid solution to a depth below the surface of atomized particles and/or (b) reacted with the dispersoid-forming element to form dispersoids in the atomized particles to a depth below the surface of said atomized particles. The atomized alloy particles are solidified as solidified alloy particles or as a solidified deposit of alloy particles. Bodies made from the dispersion strengthened alloy particles, deposit thereof, exhibit enhanced fatigue and creep resistance and reduced wear as well as enhanced corrosion and/or oxidation resistance at high temperatures by virtue of the presence of the corrosion and/or oxidation resistance imparting alloying element in solid solution in the particle alloy matrix.