Abstract: Disclosed is a sintered alloy material for valve guides, containing: 1.5% to 4% by mass of carbon; 1% to 20% by mass of copper; 0.1% to 2% by mass of tin; 0.01% or more than 0.01% and less than 0.1% by mass of phosphorus; and an iron base. The metallographic structure of the sintered alloy material has a matrix phase composed mainly of pearlite, and a free carbon phase being dispersed in the matrix phase.

Abstract: The invention concerns a pre-alloyed metal powder essentially consisting of at least two transition metals selected among iron, cobalt, nickel, copper and zinc, and also capable of containing molybdenum, as well as sintered parts obtained using said powders. Said powders have elementary grain size greater than 200 nm and less than 5 &mgr;m. The invention is particularly useful for making special steel parts or for making cutting or grinding tools.

Abstract: A powder metal blend for making a powder metal part especially a valve guide 14 for an internal combustion engine particularly suited for operation where there is little or no engine oil lubricant at the valve stem 30 and valve guide 14 interface. The powder metal blend having a chemical composition on a weight percent basis of about 2 to about 10 percent copper; about 0.5 to about 5.0 percent solid lubricant; about 1.0 to about 3.0 percent graphite; about 1.0 to about 8.0 percent bronze; about 0.2 to about 1.5 percent copper-and/or iron phosphorus; about 0.3 to about 1.0 percent fugitive lubricant; and the balance being a low alloy steel powder containing about 0.3 to about 1.0 percent manganese.

Abstract: A wear resistant sintered member exhibits superior wear resistance at the same level as those of the conventional materials without using a Co-based hard phase is provided. A first hard phase comprising Mo silicide particles dispersed in an Fe-based alloy matrix of the first hard phase and a second hard phase comprising a ferrite phase or a mixed phase of ferrite and austenite having a higher Cr concentration than the Fe-based alloy matrix surrounding a core consisting of Cr carbide particles, are diffused in an Fe-based alloy matrix, the Mo silicide particles are contained in the first hard phase in an amount of 3 to 25 % by area, and the Cr carbide particles are contained in the second hard phase in an amount of 3 to 30 % by area.

Abstract: A bearing for motorized fuel pumps comprising a graphite-dispersed copper-based sintered alloy which contains 10 to 25% by weight of Zn, 10 to 25% by weight of Ni, 0.1 to 0.9% by weight of P, and 1 to 8% by weight of C, the balance being Cu and unavoidable impurities, and which has a porosity of 5 to 25%, exhibits superior wear resistance to a high-pressure high-speed flow of a fuel.

Abstract: A coated body that has a substrate of tungsten, carbon, and cobalt, and wherein the substrate presents a surface. Eta phase is present at the surface of the substrate. Fibrous tungsten carbide grains are present at the surface of the substrate. The surface of the substrate has a surface roughness, Ra, of greater than about 12 microinches. A coating layer is on the surface of the substrate. A process for making a coated body comprising the steps of: providing a substrate comprising tungsten, carbide and cobalt, and the substrate having at least one surface with eta phase thereon; subjecting the substrate with eta phase on the surface thereof to a conversion treatment at a temperature between about 1250° C. and about 2000° C.

Abstract: A metal-infiltrated polycrystalline diamond composite tool comprising a plurality of diamond grains forming a continuous polycrystalline diamond matrix, a metallic phase being substantially palladium-free and contiguous to the continuous polycrystalline diamond matrix, wherein the metallic phase interpenetrates the continuous polycrystalline diamond matrix and substantially wets an outer surface of the continuous polycrystalline diamond matrix; and a working surface. The metallic phase is formed from an infiltrant and a wetting-enhancement layer disposed on the outer surfaces of the diamond particles, with both the infiltrant and wetting-enhancement layer being substantially palladium-free and comprising at least one metal from the group consisting of cobalt, iron, and nickel.

Abstract: An sintered iron-based powder metal body with outstandingly lower re-compacting load and having a high density and a method of manufacturing an iron-based sintered component with fewer pores of a sharp shape and having high strength and high density, the method comprising mixing, an iron-based metal powder containing at most about 0.05% of carbon, at most about 0.3% of oxygen, at most about 0.010% of nitrogen, with at least about 0.03% and at most about 0.5% of graphite powder and a lubricant, preliminarily compacting the mixture into a preform, the density of which is about 7.3 Mg/m3 or more, and preliminarily sintering the preform in a non-oxidizing atmosphere in which a partial pressure of nitrogen is about 30 kPa or less at a temperature of about 1000° C. or higher and about 1300° C. or lower, thereby forming a sintered iron-based powder metal body with outstandingly lower re-compacting load and having high deformability, the density of which is about 7.

Abstract: Polycrystalline diamond (PCD) carbide composites of this invention have a microstructure comprising a plurality of granules formed from PCD, polycrystalline cubic boron nitride, or mixture thereof, that are distributed within a substantially continuous second matrix region that substantially surrounds the granules and that is formed from a cermet material. In an example embodiment, the granules are polycrystalline diamond and the cermet material is cemented tungsten carbide. PCD carbide composites of this invention display improved properties of fracture toughness and chipping resistance, without substantially compromising wear resistance, when compared to conventional pure PCD materials.

Abstract: Metal-carbon composite powders and methods for producing metal-carbon composite powders. The powders have a well-controlled microstructure and morphology and preferably have a small average particle size. The method includes forming the particles from an aerosol of powder precursors. The invention also includes novel devices and products formed from the composite powders.

Abstract: A sintered metal sprocket for a silent chain is produced by the following steps. A base mixture is prepared, which contains a powder metallurgical iron powder, a lubricant and a graphite powder. Then, the base mixture is subjected to a compression molding while being heated at above approximately 100° C. thereby to produce a green compact. Then, the green compact is subjected to a sintering at a temperature above approximately 1180° C. For much improving the mechanical performance of the sprocket thus sintered, the same may be subjected to a carbonizing hardening or an induction hardening.

Abstract: An aluminum/diamond composite for the manufacture of metal structures having high yield strength, high stiffness, high thermal conductivity, and low coefficient of thermal expansion. The composite consists of aluminum metal with included diamond particles. The volume fraction of diamond particles may range from 5% to 80%, but is most preferably about 30% to 40%. Two methods of manufacture of the composite are disclosed. The material may be used to manufacture gun barrels, rocket nozzles, cookware, heat sinks, electronics packaging, and automotive components such as brake disks, brake drums, transmission components, and engine components.

Abstract: In a preliminary molding step 1, a metallic powder mixture 7 obtained by blending an iron-based metal powder 7a with graphite 7b such that the graphite is present in an amount of preferably not less than 0.1% by weight, more preferably not less than 0.3% by weight, is compacted into a preform 8 having a density of not less than 7.3 g/cm3. In a provisional sintering step 2, the preform 8 is provisionally sintered at a predetermined temperature to form a metallic powder-molded body 9 having a structure in which the graphite remains along a grain boundary of the metal powder. In a re-compaction step 3, the metallic powder-molded body 9 is re-compacted into a re-compacted body 10. In a re-sintering step 4, the re-compacted body 10 is re-sintered to obtain a sintered body 11. In a heat treatment step 5, the sintered body 11 is heat-treated to obtain a heat-treated sintered body 11.

Abstract: The present invention relates to a coated cemented carbide insert with a binder phase enriched surface zone. The WC-grains have an average grain size in the range 1.0-3.5 &mgr;m, preferably 1.3-3.0 &mgr;m and the number of WC-grains larger than 2 times the average grain size is less than 10 grains/cm2 measured on a representative polished section 0.5 cm2 large, preferably less than 5 grains/cm2, and the number larger than 3 times the average grain size is less than 5 grains/cm2, preferably less than 3 grains/cm2. The cemented carbide is made by powder metallurgical methods and is in particular characterized in that the cooling rate, CR, from the sintering temperature, ST, exhibits the relationship 10<CR·(ST-1300)/1000<17.

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: A metal-infiltrated polycrystalline diamond composite tool comprising a plurality of diamond grains forming a continuous polycrystalline diamond matrix, a metallic phase being substantially palladium-free and contiguous to the continuous polycrystalline diamond matrix, wherein the metallic phase interpenetrates the continuous polycrystalline diamond matrix and substantially wets an outer surface of the continuous polycrystalline diamond matrix; and a working surface. The metallic phase is formed from an infiltrant and a wetting-enhancement layer disposed on the outer surfaces of the diamond particles, with both the infiltrant and wetting-enhancement layer being substantially palladium-free and comprising at least one metal from the group consisting of cobalt, iron, and nickel.

Abstract: A mixture for a powder metallurgy product, including iron powder, graphite powder and copper (Cu) of about 3.0 to about 5.0 weight percent. Iron powder includes iron grains which contain MnS therein. The mixture contains the MnS of about 0.65 to about 1.40 weight percent. The graphite powder is contained in the mixture such that an amount of carbon (C) in the powder metallurgy product is about 0.3 to about 0.7 weight percent. An amount (wt % C) of the carbon and an amount (wt % Cu) of the copper is determined to obtain a target fatigue strength FS (MPa) and a target hardness HR (HRB) based on a relation FS=66.63×(wt % C)+22.61×(wt % Cu)+280.84 HR=22.96×(wt % C)+2.99×(wt % Cu)+78.91.

Abstract: A superhard filler hardmetal having a superhard material filler, binder metal or matrix and in some instances at least a first hard component is disclosed. The superhard filler hardmetal has a porosity rating of substantially A06, B00, C00 or better and may be essentially pore free, i.e., A00, B00, C00. The superhard filler hardmetal is formed by mechanically mixing a superhard material, in some instances at least a first hard component and a binder metal or matrix precursor, shaping the mixture into a green body and consolidating the green body at a preselected temperature, superatmospheric pressure and time at temperature and time at superatmospheric pressure sufficient to form the superhard filler hardmetal. The consolidation preferably occurs without the formation of a liquid in the body and at least a portion of the time at superatmospheric pressure is at the preselected temperature. Diamond filler and boron nitride filler are examples of superhard materials usable as filler.

Abstract: An iron-graphite composite powder having a microstructure comprising carbon clusters embedded in a ferrous matrix is disclosed. Also disclosed is a process for preparing the iron-graphite composite powder, a process for preparing sintered articles from this composite powder and the sintered articles prepared thereby.

Abstract: A process for producing a high-density iron-based green compact is provided that can form a green compact with a high density. Also provided is a process for producing a sintered compact from the green compact. A specified combination lubricant is applied to the surface of a die for compacting by electrical charging, wherein the combination lubricant includes a first lubricant having a melting point that is higher than a preset compacting temperature, and a second lubricant having a melting point that is lower than a compacting temperature. A heated iron-based powder mixture is filled into the die, followed by compacting, whereby a green compact is formed. The green compact can be sintered to provide a sintered compact.

Abstract: The present invention relates to s a sintered alloy having an excellent wear resistance for a valve seat and a method of producing the same. More particularly, the present invention relates to the sintered alloy having an excellent wear resistance for a valve seat, which is produced by a sub-zero treatment for a metal powder comprising Fe(iron) as a main component, C(carbon), Si (silicon), Cr(chromium), Mo(molybdenum), Co(cobalt), Mn(Manganese), Pb(lead), V(vanadium) and W(tungsten) so that amount of metallic particles separated from a base matrix decreases and a size of the separated metallic particle becomes small when an abrasion of the sintered alloy is in proceed, thereupon a wear resistance and an impact resistance are improved and a self-lubricity and a machinability are enhanced, and a method of producing the same.

Abstract: The invention relates to an iron-based high-temperature wear-resistant sintered alloy. This alloy contains 3.74-13.36 wt % W, 0.39-5.58 wt % V, 0.2-5.78 wt % Cr, 0.1-0.6 wt % Si, 0.39-1.99 wt % Mn, 0.21-1.18 wt % S, and up to 2.16 wt % C. This alloy includes 20-80 wt % of a first phase and 80-20 wt % of a second phase, each distributed therein, in the form of spots. The first phase contains 3-7 wt % W, up to 1 wt % Cr, 0.1-0.6 wt % Si, 0.2-1 wt % Mn, 0.1-0.6 wt % S, and up to 2.2 wt % C. The first phase may contain 0.5-1.5 wt % V, and in this case the vanadium content of the alloy becomes 0.79-5.88 wt %. The second phase contains 7-15 wt % W, 2-7 wt % V, 1-7 wt % Cr, 0.1-0.6 wt % Si, 0.2-1 wt % Mn, 0.1-0.6 wt % S, and up to 2.2 wt % of C. Each phase contains 0.3-1.6 wt % MnS and a carbide of at least tungsten, which are dispersed therein. The second phase further contains 10-20 areal % tungsten carbide (particle diameter: ≧1 &mgr;m) dispersed therein. The alloy further contains 0.

Abstract: Powder product for the protection of molds for centrifugal casting of cast iron tubes, and a method for its production. The powder contains a mixture of a silicon-based inoculating agent and a mineral powder, the silicon-based inoculating product comprising waste masses from synthesis of alkyl- or aryl- halosilanes, from which tin and optionally copper has been removed. The mineral powder may contain at least one material selected from the group consisting of carbon and a fluoride.

Abstract: A method for producing a material includes providing a metallurgical powder including iron, 1.0 to 3.5 weight percent copper, and 0.3 to 0.8 weight percent carbon. At least a portion of the powder is compressed at 20 tsi to 70 tsi to provide a compact, and subsequently the compact is heated at high temperature and then cooled at a cooling rate no greater than 60° F. per minute to increase the surface hardness of the compact to no greater than RC 25. The density of at least a region of the sintered compact is increased, by a mechanical working step or otherwise, to at least 7.6 grams/cc. The sintered compact is then re-heated to high temperature and cooled at a cooling rate of at least 120° F./min. so as to increase the surface hardness of the compact to greater than RC 25, and preferably at least RC 30. Material made by the method of the invention also is disclosed.

Abstract: An aspect of this invention is an electrode rod for spark alloying, comprising a compact of a first powder of a first component which comprises a metal selected from a group of Fe, Co, Ni, metals of 4a, 5a and 6a of the periodic table and Si, and a second powder of a second component which is capable of self-propagating high temperature synthesis to form with said first component carbide, nitride, boride, silicide or intermetallic compound, said first and second powders being mixed intimately with each other and formed into an axial rod.

Abstract: A mixed powder for powder metallurgy process, comprises prealloy type steel mother powder containing alloy components in a range of 1.5 to 4, alloyed micro powder and Ni powder. A preparation method of iron base sintered compact by blending this mixed powder with graphite powder, compressed powder molding the same and sintering at 1050 to 1250° C., and an iron base sintered compact of high tensile strength and fatigue strength obtained by this preparation method.

Abstract: Disclosed is a sintered Ti-based material product derived from injection molding of a powder material. The outer layer region of the product comprises a lower amount of carbon than the inner layer region of the same. The inner layer region comprises a Ti-based carbide which has an average grain size of not less than 1 &mgr;m and which is dispersed in the inner structure to have an area fraction of not less than 0.1% to not more than 20%. The outer layer region comprises a lower amount of Ti-based carbide than the inner layer region. There can be observed an area fraction of less than 0.1% of the Ti-based carbide at the surface of the sintered Ti-based material product.

Abstract: There is provided a copper-based sliding alloy excellent in wear resistance and anti-seizure property. A phase of 2 to 30 wt. % lead is dispersed in the copper alloy. This lead phase contains 0.1 to 6 vol. % hard particles such as SiC, SiO2, Si3N4, Al2O3, TiC, WC and TiN having an average particle size of 5 to 25 &mgr;m. Because hard particles are included in the lead phase, wear resistance is excellent and anti-seizure property is improved. The lead phase, which is soft, serves as a cushion and the attack on a mating member by hard particles is reduced. Further, the falling-off of lead is minimized because the lead phase also includes the hard particles.

Abstract: In a cemented carbide, at least one compound 3 including a carbide, a nitride or carbo-nitride of at least one component selected from IVa, Va and VIa group elements or a solid solution thereof exists in at least some WC crystal grains 1. Preferably the compound 3 is in the form of compound grains 3 comprising a carbide, a nitride or a carbo-nitride of Ti, Zr, Hf or W or a solid solution thereof, having an average grain diameter smaller than 0.3 &mgr;m. The compound grains make up at most 10% of the cross-sectional area of the WC crystal grains that contain the compound grains, while at least 10% of the total cross-sectional area of the cemented carbide is made up of such WC crystal grains that contain the compound grains.

Abstract: A method of making a bonded, coherent material comprising a mass of diamond crystals in a matrix, which optionally contains another phase. The method includes the steps of providing a source of diamond crystals, providing a plurality of diamond centers defined by diamond crystals, producing a reaction mass by bringing the source and growth centers into contact with a solvent/catalyst, subjecting the reaction mass to conditions of elevated temperature and pressure suitable for crystal growth in the reaction zone of a high temperature/high pressure apparatus to produce the material, and removing the material from the reaction zone. The method is characterized by providing the necessary supersaturation of carbon in the solvent/catalyst, at least in part and preferably predominantly, by a selection of particle size difference between the source crystal and the growth centers. The mass of diamond crystals in the matrix of the bonded, coherent material of the invention has a high concentration of twinned diamonds.

Abstract: A diamond sintered body having high wear resistance, chipping resistance, shock resistance and thermal conductivity is provided. The diamond sintered body includes sintered diamond particles and a sintering aid as the remainder. The content of the sintered diamond particles is at least 80% by volume and less than 99% by volume. The sintered diamond particles have a particle size in the range from at least 0.1 &mgr;m to at most 70 &mgr;m. The sintered diamond particles next to each other are directly bonded. The sintering aid includes at least one kind selected from tungsten, iron, cobalt and nickel. The percentage of the tungsten in the sintered body is in the range from at least 0.01% by weight to at most 8% by weight.

Abstract: Heat-dissipating microcircuit substrate, having coefficients of thermal expansion adjusted to match the materials of the microcircuit mounted thereupon, are manufactured by powder metallurgy using carbides resulting from the combination of various types of carbons and wetting agents.

Abstract: A powder metallurgy article formed of a sulfur-containing, precipitation-hardenable, stainless steel alloy is described. The article has a unique combination of strength, ductility, processability, and machinability. The powder metallurgy article is formed of a stainless steel alloy having the following composition in weight percent. C 0.03 max. Mn 1.0 max. Si 0.75 max. P 0.040 max. S 0.010-0.050 Cr 10-14 Ni 6-12 Ti 0.4-2.5 Mo 6 max. B 0.010 max. Cu 4 max. Co 9 max. Nb 1 max. Al 1 max. Ta 2.5 max. N 0.03 max. The balance of the alloy is iron and the usual impurities. The powder metallurgy article according to this invention is characterized by a fine dispersions of titanium sulfides that are not greater than about 5 &mgr;m in major dimension. A method of preparing the powder metallurgy article is also described.

Abstract: There is disclosed a high temperature sliding alloy consisting of, by weight, 2 to 8% Cr, 2 to 10% Fe, 0.1 to 1.5% Si, 2 to 22% Co, 1.4 to 11% Mo, and the balance Ni, wherein 1 to 35% by weight of Co—Mo—Cr—Si base hard particles are dispersed in a matrix of the sliding alloy, and each of the hard particles has an oxide phase formed on a surface thereof. With this construction, the sliding alloy exhibits excellent sliding properties and particularly a low friction coefficient and excellent wear resistance in the temperature range of from a room temperature to 900° C.

Abstract: A process for producing a sintered powder metal body is disclosed. A powdery mixture is prepared by blending a graphite powder in amount of not less than 0.3% by weight with an iron based metal powder. The powdery mixture is compacted into a preform having a density of not less than 7.3 g/cm.sup.3. The preform is sintered at a temperature of 800-1000.degree. C. to form the sintered powder metal body having a predetermined structure. The predetermined structure of the sintered powder metal body includes iron based metal particles and graphite particles retained between the iron based metal particles.

Abstract: A powdered metal blend mixture for making a powdered metal part especially a valve seat insert. The mixture includes 15 to 30 wt. % of a valve steel powder, 0 to 10 wt. % nickel, 0 to 5 wt. % copper, 5 to 15 wt. % of a ferro-alloy powder, 0 to 15 wt. % of a tool steel powder, 0.5 to 5 wt. % of a solid lubricant, 0.5 to 2 wt. % graphite, 0.3 to 1.0% of a temporary lubricant, and the balance being substantially a low alloy steel powder containing 0.6 to 2.0 wt. % molybdenum, 0 to 5 wt. % nickel, and 0 to 3.0 wt. % copper. The present invention provides improved high temperature wear and corrosion resistance over prior art materials as well as improved machinability. The blend of the present invention provides a relatively high density material that allows for a single press and sinter technique.

Abstract: A valve seat made of an iron base sintered alloy for internal combustion engines comprises of hard particles of hardness 700-1300 Hv dispersed by 3-20% by volume in a matrix phase comprising comprising of a 5-40% psarlite phase, a 20-60% fine carbide dispersed phase, and a 5-20% high alloy diffusd phase. The hard paricles are preferably selected from a group of Mo--Ni--Cr--Si--Co intermetallic compound particles, Cr--Mo--Co intermetallic compound particles, and Fe--Mo alloy particles. The iron base sinteed alloy is conpised of, by weight, C: 0.2-2.0%, Cr: 1.0-9.0%, Mo: 1.0-9.0%, Si: 0.1-1.0%, W: 1.0-50%, V: 0.2-3.0%, one or more Cu, Co and Ni of 0.5-10.0% in total, and the remainder substantial Fe.

Abstract: The invention concerns metal powder granulates comprising one or a plurality of the metals Co, Cu, Ni, W and Mo. The invention further concerns a method for the production of these granulates and the use thereof. The production method is characterized in that a metal compound comprising one or a plurality of the groups comprising oxides, hydroxides, carbonates, hydrogenocarbonates, oxalates, acetates, formiates with binder and optionally in addition between 40 and 80% solvent, relative to the solids content, is granulated as the starting component, and the granulates are thermally reduced in a hydrogen-containing gaseous atmosphere to form the metal powder granulates, the binder and the solvent, if used, being removed completely.

Abstract: A metal-matrix diamond or cubic boron nitride composite and method of making the same are disclosed. The metal-matrix/diamond composite includes grains of diamond uniformly distributed in a metal matrix. Alternatively, grains of cubic boron nitride may be used. Suitable metals for the metal matrix material may include nickel, cobalt, iron, and mixtures or alloys thereof. Other transition metals also may be used. The metal-matrix/diamond or metal-matrix/cubic boron nitride composite has high fracture toughness due to its fine microstructure. Such a metal-matrix/diamond or metal-matrix/cubic boron nitride composite is suitable for use in blanks or cutting elements for cutting tools, drill bits, dressing tools, and wear parts. It also may be used to make wire drawing dies.

Abstract: The present invention includes iron-carbon compacts and a process for making them. The process includes preparing a slurry comprising iron powder, furfuryl alcohol, and a polymerization catalyst for initiating the polymerization of the furfuryl alcohol into a resin, and heating the slurry to convert the alcohol into the resin. The resulting mixture is pressed into a green body and heated to form the iron-carbon compact. The compact can be used as, or machined into, a magnetic flux concentrator for an induction heating apparatus.

Abstract: The invention relates to diamond coatings and the growth of diamond coatings suitable for tools, wear parts, and the like. The invention controls process conditions to produce polycrystalline coatings having progressively finer grain size in the direction of the outer surface. This enhances the wear resistance and finish characteristics of the parts and tools. In one process, chemical vapor deposition is used to grow a first region over a substrate with a plurality of nucleation sites and the first region transitions into polycrystalline diamond grains growing progressively smaller to an average grain size of less than three microns.

Abstract: A powder-metallurgically produced hot-work steel consists (in weight percent) of: 0.25-0.45 carbon, 2.40-4.25 chromium, 2.50-4.40 molybdenum, 0.20-0.95 vanadium, 2.10-3.90 cobalt, 0.10-0.80 silicon, 0.154-0.65 manganese, the balance being iron and possibly impurities resulting from production. The powder charge with the above-mentioned composition is simultaneously exposed to high compacting pressures and high compacting temperatures in a hot isostatic press.

Abstract: A brazing rod for use in depositing an abrasive metal coating on a metal substrate. The brazing rod comprises particulate abrasive material selected from the group consisting of diamond particles and mixtures of diamond particles and carbide particles and a matrix comprising a braze alloy which is sufficiently sintered together to bind the particulate abrasive material into a rigid rod. The braze alloy contains one component selected from the group consisting of nickel, nickel alloy, silver, silver alloy, gold, gold alloy, copper, copper alloy and mixtures thereof, and a second component selected from the group consisting of iron, iron alloy, cobalt, cobalt alloy, tin, tin alloy, boron, silicon, chromium, chromium alloy and mixtures thereof. The diamond particles are coated with a material selected from the group consisting of tungsten, molybdenum, chromium, nickel, iron, cobalt, palladium, tungsten carbide, molybdenum carbide, chromium carbide and iron carbide.

Abstract: A sintered alloy having superb wear resistance consisting, percent by weight of, as a whole, Ni in the amount of 1.35 to 19.61%, Cr in the amount of 0.9 to 11.05%, Mo in the amount of 1.44 to 9.09%, Co in the amount of 3.6 to 20.05%, V in the amount of 0.018 to 0.26%, Si in the amount of 0.1 to 0.75%, C in the amount of 0.35 to 1.5%, and the balance of Fe, and the sintered alloy exhibiting a metallographic structure in which the following hard phases are dispersed in a mixed structure of martensite, sorbite, and austenite: a first hard phase comprising, a hard phase as a core mainly consisting of Mo suicide, and a diffused phase including diffused Co surrounding the hard phase; and a second hard phase comprising, a hard phase as a core consisting of Cr carbide, and a mixed phase of ferrite and austenite surrounding the hard phase.

Abstract: An improved coldforming tool made of a zone in a tungsten carbide-cobalt cemented carbide is disclosed. The tool, preferably a wire drawing nib, contains WC with a mean grain size of 1.5-2 .mu.m and 5-7 weight % Co and with a carbon content close to saturation level and sufficient to exhibit cobalt magnetic measurements of 92%-98% of that of pure cobalt.

Abstract: The invention relates to a sintered alloy. This sintered alloy includes 3-13.4 wt % of W, 0.4-5.6 wt % or 0.8-5.9 wt % of V, 0.2-5.6 wt % of Cr, 0.1-0.6 wt % or 0.6-5.0 wt % of Si, 0.1-0.6 wt % or 0.2-1.0 wt % of Mn, 0.6-2.2 wt % of C, and a balance of Fe. The sintered alloy includes first and second phase which are distributed therein, in a form of spots, respectively. The second phase is in an amount of from 20 to 80 wt %, based on the total weight of the first and second phases. The first phase contains 3-7 wt % of W, 0.5-1.5 wt % of optional V, up to 1 wt % of Cr, 0.1-0.6 wt % or 0.6-5.0 wt % of Si, 0.1-0.6 wt % or 0.2-1.0 wt % of Mn, up to 2.2 wt % of C, and a balance of Fe. The second phase contains 3-15 wt % of W, 2-7 wt % of V, 1-7 wt % of Cr, 0.1-0.6 wt % or 0.6-5.0 wt % of Si, 0.1-0.6 wt % or 0.2-1.0 wt % of Mn, up to 2.2 wt % of C, and a balance of Fe. When the manganese contents of the first and second phases and the total of the sintered alloy are respectively in a range of from 0.2 to 1.

Abstract: An iron based powder mixture for powder metallurgy is provided which can produce a sintered material having by far higher machinability and sliding properties than conventional sintered materials, and also a sintered material containing alloy elements but having adaptability to sizing even after sintering; it comprises an atomized iron powder comprising S in a content of 0.03 to 0.30 wt %, Mn in a content of 0.05 to 0.40 wt % and the balance Fe and incidental impurities, to which is added one or more than one B-containing compound powder selected from boron nitride (BN), boric acid (H.sub.3 BO.sub.3), boron oxide (B.sub.2 O.sub.3) and the like in an amount of 0.001 to 0.3 wt % expressed as B, and incorporated with an MnS powder in an amount of 0.05 to 1.0 wt %, optionally alloyed partially with or prealloyed with Ni, Mo and Cu.

Abstract: A blend of pre-alloyed stainless steel powder for use in producing sintered stainless steel, said powder consisting essentially of, by weight, up to 0.05% carbon, 22% to 26% chromium, 10% to 24% nickel, 2.7% to 5% molybdenum, 0.1% to 1% boron, up to 2.0% manganese, up to 2.0% silicon, balance iron and residuals, together with manganese sulfide particles added thereto until they comprise up to 4%, by weight, of the overall blend, experimental results having shown that the blend offers significant improvements in the machinability of the resulting steel. The patent also claims a method for making sintered steel using the blend, as well as the sintered steel resulting from the process.

Abstract: A manufacturing method and products of metallic friction materials includes processes of 1. preparing powder materials, 2. mixing copper as a base, proper proportion of iron powder or steel wool, aluminum powder, zinc or tin or lead powder, graphite powder and alumina or silicon dioxide powder, 3. pressing mixed materials into green bodies under 375.about.625 MPa at room temperature, 4. pre-heat treating the green bodies in an air furnace with temperature raised to 100.about.300.degree. C. for 1.about.3 hours, 5. sintering the green bodies into test samples under 350.about.750 MPa for 24.about.60 hours to gain sintered friction materials having an oxidized layer of less than 1 mm thick, 6. processing and grinding the sintered test samples with grinders to remove the oxidized layer, 7. washing the outer surface of the sintered test samples ground into finished products. The method of the invention may reduce largely difficulty in manufacturing processes, the investment and productive cost.

Abstract: The invention relates to an aluminum powder blend and sintered components produced from the aluminum powder blend. The powder is based on the precipitation hardenable 7000 series Al-Zn-Mg-Cu alloys with trace addition of lead or tin. The powder blend comprises 2-12 wt. % zinc, 1-5 wt. % magnesium, 0.1-5.6 wt. % copper, 0.01-0.3 wt. % lead or tin, and the balance aluminum. The invention also provides a composite powder comprising the foregoing powder blend and a reinforcing element or compound.