Abstract: The invention relates to a method of preparing metal powder comprising: preparing a simple or mixed oxalate of one or more metals formed of particles with needle-like morphology having a mean acicularity ratio (length/diameter) of from 4 to 20, and a length of from 5 to 10 microns and converting said oxalate to metal or metal alloy powder by reducing treatment with gaseous hydrogen. The conversion of said oxalate can be carried out by decomposing said oxalate, in air, to an oxide and then reducing said oxide to metal or metal alloy. The metal is chosen from among the rare earth metals and the transition metals, preferably from among iron, cobalt, and nickel. The method is particularly suitable for making iron powder metal having a spongy and filament-like microstructure which makes it suitable for use in heating composition for thermo-piles. In addition, the invention relates to metal compacts unstoved or annealed which are obtained by applying compaction pressure to the powders according to the invention.

Abstract: A method of fabricating a foamed metal structure using a powder supply of metal particles, comprising: (a) introducing the powder supply along with foaming agent particles into a propellant gas to form a gas/particle mixture stream; (b) projecting the mixture stream at a critical velocity of at least sonic velocity onto a metallic substrate to create a deposit of pressure-welded metal particles containing the admixed foaming agent; and (c) subjecting at least the coating of the substrate to a thermal excursion effective to activate expansion of the foaming agent while softening the metal particles for plastic deformation under the influence of the expanding gases.

Abstract: The present invention relates to cemented carbide tools for coldforming and drawing operations. The cemented carbide comprises WC with an average grain of <1 &mgr;m and 0.5-4 weight-% binder phase consisting of Co and Ni, <0.5 wt-% Mo, and <1 wt-% grain growth inhibitors V and/or Cr. The weight ratio Co:(Co+Ni) is 0.25-0.75 and the structure contains 1-5 vol-% of finely distributed eta phase with a size <5 &mgr;m.

Abstract: An iron-based mixed powder for use in powder metallurgy has an apparent density of at least about 3.1 Mg/m3, is excellent in die filling property and compressibility and without segregation, and includes an iron-based powder to which alloying powder is adhered at the surface by binder and free lubricant. The iron-based powder includes an atomized iron powder, or a mixed powder of an atomized iron powder and a reduced iron powder.

Abstract: The invention shows how powder injection molding may be used to form a continuous body having multiple parts, each of which has different physical properties such as magnetic characteristics or hardness. This is accomplished through careful control of the relative shrinkage rates of these various parts. Additionally, care is taken to ensure that only certain selected physical properties are allowed to differ between the parts while others may be altered through relatively small changes in the composition of the feedstocks used. An additional application of the present invention is a process for forming, in a single integrated operation, an object that is contained within an enclosure while not being attached to said enclosure. This is accomplished by causing the shrinkage rate of the object to be substantially greater than that of the enclosure. As a result, after sintering, the object is found to have detached itself from the enclosure and is free to move around therein.

Abstract: The present invention provides an amalgamatable dental alloy powder for making an amalgam having a low initial mercury vapor release rate having a composition comprising 50-80 wt % Ag; 10-30 wt % Cu, and 10-35 wt % Sn, and optionally less than 7 wt % of Pd, which is prepared by subjecting a single-alloy powder having a particle size ranging from 1 to 55 microns with a majority thereof having a particle size less than 20 microns to a heat treatment, or separately subjecting a Ag—Cu—Sn powder having a particle size ranging from 1 to 70 microns with a majority thereof having a particle size less than 30 microns and a Ag—Cu—Pd powder having a particle size ranging from 1 to 100 microns with a majority thereof having a particle size less than 45 microns to heat treatments, and subjecting the heat treated powders to a pickling treatment.

Abstract: A nickel powder for multilayer ceramic capacitors according to the present invention is characterized in that an average particle size of a nickel powder is 0.1 to 1.0 &mgr;m, and the number rate of a nickel powder having a particle size of 2 &mgr;m or more is not more than 700 per million. As a process for producing such nickel powder, a process in which slurry containing a nickel powder having an average particle size of 0.1 to 1.0 &mgr;m in the amount of 5 to 25% by weight is classified using a hydrocyclone in which powders in a powder-liquid mixture are classified into at least coarse particles and fine particles, is preferred. According to the nickel powder of the present invention, the content of coarse particles is low, the particle size distribution is narrow, and the surface roughness in the paste state is decreased, and therefore, the nickel powder is extremely suitable for multilayer ceramic capacitors.

Abstract: An iron-based powder composition is provided that is greatly flowable and compactible and less dependent on temperature with respect to flowability and compactibility at room temperature or during warming. The iron-based powder composition includes an iron-based powder, a lubricant melted and fixed to the iron-based powder, an alloying powder bonded to the iron-based powder with the aid of the lubricant, and a free lubricant. One or more constituent members are coated with an organosiloxane layer in a coating ratio of greater than about 80%. The organosiloxane has phenyl groups as a functional group. The lubricant melted and fixed to the iron-based powder is a composite melt composed of a calcium soap and a lithium soap, or a composite melt composed of a calcium soap and an amide lubricant. The free lubricant is a mixed powder composed of an amide lubricant and a methyl polymethacrylate powder, or a lithium soap powder. A process for producing the iron-based powder composition is also provided.

Abstract: In the production of reduced iron by agglomerating a mixed powder of an iron material and a reducing agent to form compacts like briquettes or pellets, and reducing the compacts in a high temperature atmosphere, when the temperature of reduced compacts is 900° C. or higher, the oxide content in the reduced compacts is set at 11% or more, and the basicity of the reduced compacts is set at 0.5 or higher.

Abstract: Disclosed is a method for reducing the dioxin content of the off-gas in operating a sintering plant, in which prior to sintering a material catalytically active in decomposing dioxins and in the form of fine grains or dust is admixed. The admixed catalytically active material prevents the fresh formation of dioxins and reduces the content of dioxins in the off-gas flowing through the material for sintering. The catalytically active material) is incorporated in the agglomerate of material for sintering which is forming and can be disposed of reliably and without danger via the slag formed in the following blast-furnace process.

Abstract: A pellet for use in electrolytic capacitors is comprised of a powder selected from one of Tantalum and Niobium. The pellet is porous, free from oxygen, annealed by heat, and diffused with nitrogen with all these attributes being achieved in an oxygen free environment. The method of producing the pellet involves the steps of taking a powder selected from one of Tantalum and Niobium pressing the powder into a self-contained pellet; removing any oxygen in the pellet; annealing the pellet; and subjecting the pellet to nitrogen gas so that the nitrogen diffuses into the pellet to reduce DLC, with all these steps taking place in an oxygen free environment.

Abstract: A blade material, containing diamond particles below about 100 &mgr;m in diameter, is formed as a cutting material where the diamond particles serve as cutting agents while being fixed in a retaining matrix. The retaining matrix substantially includes Titanium or a Titanium alloy containing more than about 50 wt % of Titanium and fixes the diamond particles in place through a multi-step process.

Abstract: To provide a method for forming undercuts of a metal injection molded product by simple processes and metal injection molded products having undercuts formed by the forming method thereof, steps are included of injection-molding a feed stock containing metal powder and binding resin, forming undercuts to an injection green body obtained by the injection-molding, and sintering after debinding the injection green body formed with undercuts. It is preferable that undercuts are formed by deforming at least one part of an injection green body; it is more preferable that they are deformed by pressing with a pressing member.

Abstract: The present invention relates to a method of forming a powder rod core comprising injecting a powder mix material into a mold, moving the mold to a curing station, and injecting material into a second mold.

Abstract: The present invention concerns powder compositions including iron-containing powders, additives, lubricant and flow agents. The powder compositions essentially consist of iron-containing particles having additive particles bonded thereto by a molten and subsequently solidified lubricant for the formation of aggregate particles and from about 0.005 to about 2 percent by weight of a flow agent having a particle size below 200 nanometers.

Abstract: A magnetic powder feeding method for feeding magnetic powder into a cavity of a pressing apparatus includes the steps of: providing magnetic powder outside of the cavity; forming a magnetic field in a space including the cavity; and moving the magnetic powder into the cavity using a force exerted on the magnetic powder by the magnetic field, while the magnetic powder is oriented in a direction of the magnetic field. In the method, the step of moving of the magnetic powder into the inside of the cavity is performed after the start of the application of the magnetic field.

Abstract: An object of the present invention is to provide a method of producing an Ag—ZnO electric contact material which can uniformly disperse ZnO micrograms in Ag; which maintains low contact resistance; which exhibits enhanced welding resistance and wear resistance; and which is suitable in view of production costs. The method of producing an Ag—ZnO electrical contact material comprises casting Ag and Zn at predetermined proportions and subjecting the resultant Ag—ZnO alloy to internal oxidation so as to disperse ZnO in Ag, the method being characterized in that an Ag—Zn alloy comprising 5-10 wt. % (as reduced to weight of metal) Zn, the balance being Ag, is formed into chips; the chips are subjected to internal oxidation; the internally oxidized chips are compacted to thereby form billets; the billets are pressed and sintered; and subsequently, the sintered billets are extruded, to thereby yield uniform dispersion, in Ag, of ZnO micrograms.

Abstract: High energy flux infrared heaters are used to treat an object having a surface section and a base section such that a desired characteristic of the surface section is physically, chemically, or phasically changed while the base section remains unchanged.

Abstract: A method for producing a compact of rare earth alloy powder of the present invention includes: a powder-filling step of filling rare earth allow powder in a cavity formed by inserting a lower punch into a through hall of a die of a powder compacting machine; and a compression step of pressing the rare earth alloy powder while applying a magnetic field, the steps being repeated a plurality of times. When the (n+1)th (n is an integer equal to or more than 1) stage compression step is to be carried out, the top surface of a compact produced in the n-th stage compression step is placed at a position above the bottom surface of a magnetic portion of a die.

Abstract: A magnetic mixture comprising at least two kinds of powders which are uniformly mixed with each other. Each powder exhibits a significant magnetic property when its constituent elements have a predetermined composition ratio. Magnetic properties of each powder are retained in the magnetic mixture which exhibits, as a whole, a soft magnetic property. The magnetic mixture is useful as a raw material for a powder magnetic core.