Abstract: A surface treatment method for a metal material is provided which includes applying diluted sulfuric acid to a surface of the metal material that is composed primarily of iron, performing a heat treatment on the metal material in the presence of at least one of CO, CO2 and organic gas under nitriding conditions under which a nitrided layer is formed in a superficial layer of the metal material after the application of the diluted sulfuric acid to form a carbon film which includes at least one of carbon nanocoils, carbon nanotubes and carbon nanofilaments on a surface of the nitrided layer of the metal material.

Abstract: The present invention provides a grease composition which has excellent conductivity and can rapidly remove static electricity generated by using a bearing. The grease composition comprises a base oil, a thickener and a tungsten disulfide powder, wherein the average particle diameter of the tungsten disulfide powder is 0.5 to 5.0 ?m and the amount of tungsten disulfide powder based on 100 parts by mass of the total amount of base oil and thickener is 2.0 to 4.0 parts by mass.

Abstract: A surface treatment method for a metal material is provided which includes applying diluted sulfuric acid to a surface of the metal material that is composed primarily of iron, performing a heat treatment on the metal material in the presence of at least one of CO, CO2 and organic gas under nitriding conditions under which a nitrided layer is formed in a superficial layer of the metal material after the application of the diluted sulfuric acid to form a carbon film which includes at least one of carbon nanocoils, carbon nanotubes and carbon nanofilaments on a surface of the nitrided layer of the metal material.

Abstract: A casting process for producing a metal matrix composite comprising a first phase or a matrix of a metal or metal alloy and a second phase of particles dispersed in the matrix, comprising the steps of: preparing a melt of the metal or metal alloy in a vessel; feeding the particles to the melt; applying ultrasonic vibration to the melt while electromagnetically stirring the melt; and then causing solidification of the melt. The process preferably further comprises the step of applying ultrasonic vibration to the melt while electromagnetically stirring the melt during the solidification of the melt.

Abstract: A method and apparatus for forming a layer of plating on a base material and a method for manufacturing a three dimensional object. The plating apparatus includes a nozzle for delivering a stream of plating fluid and an electric source for applying a voltage between the base material and the nozzle. The nozzle has an outer wall and a stem located at its center. The nozzle delivers plating fluid from the opening of the nozzle in an annular manner to produce a stream that has a substantially uniform flow velocity when the stream hits the base material. In an another embodiment, the nozzle has surrounding conduit for conducting air. The air increases the velocity of a peripheral portion of the stream. To manufacture a three dimensional object, a plating layer is deposited, and the nozzle is moved to form a desired shape while piling the layer.

Abstract: A method of making a composite structure including at least a plating film disposed on a substrate having at least a surface portion formed from a metallic base material. The method includes the steps of discharging a composite plating solution containing insoluble particles from a nozzle and impacting the composite plating solution on the surface portion of the substrate at a predetermined flow rate. During at least a portion of the discharging and impacting steps, the surface portion of the substrate is abraded with the insoluble particles in the plating solution discharged from the nozzle. A voltage can be applied between the base material and the nozzle, which are electrically connected by the plating solution, to thereby deposit a plating film on the surface portion of the substrate by electroplating.

Abstract: A composite plating film is prepared from a composite plating solution containing a metal matrix and insoluble particles 4 dispersed therein or deposited therewith. The composite plating film has a non-uniform concentration of insoluble particles along a direction of the thickness of the composite film. The non-uniform concentration is achieved by changing the discharge rate of composite plating solution during deposition of the film on the base material.

Abstract: A method of manufacturing a composite material by melt-spraying, comprising the steps of melt-spraying a metal as the main constituent of the composite material onto a base plate and injecting a reinforcing substance comprising discontinuous fibers into the metal melt spray stream upstream of the base plate to effect mixing of the reinforcing substance in the melt-sprayed stream of metal within a temperature range without producing a resultant reaction layer between said metal and said reinforcing substance.