Abstract: A sintered iron-based powder metal body with 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.

Abstract: A supported catalyst is provided comprising catalyst metal nanoparticles having an average particle size of 3.0 nm or less, or more typically 2.0 nm or less, and typically having a standard deviation of particle size of 0.5 nm or less, which are supported on support particles at a loading of 30% or more. Typical catalyst metals are selected from platinum, palladium, ruthenium, rhodium, iridium, osmium, molybdenum, tungsten, iron, nickel and tin. Typical support particles are carbon. A method of making a supported catalyst is provided comprising the steps of: a) providing a solution of metal chlorides of one or more catalyst metals in solvent system containing at least one polyalcohol, typically ethylene glycol containing less than 2% water; b) forming a colloidal suspension of unprotected catalyst metal nanoparticles by raising the pH of the solution, typically to a pH of 10 or higher, and heating said solution, typically to 125 ° C.

Abstract: An inclined function material is formed with an iron layer on a surface of a carbon material. This material can be used in a carbon base member and does not limit the choice of desired characteristics in a carbon base member. The process by which the carbon base member is formed also ensures the iron layer is integrated firmly with the surface of the carbon material. A suitable amount of an iron powder having a particle diameter of 5 to 15 &mgr;m is placed directly on the surface of a carbon material, which is sintered in advance under suitable conditions, and stuck to the surface uniformly and flatly. The iron powder and the carbon material are sintered at 1000° C. to 1300° C. and preferably 1050 to 1150° C. for 1 to 2 hours and preferably about 1.5 hours to form a carbon base member in which the iron layer is formed on one surface of the carbon base member.

Abstract: A copper graphite composite material suitable for use in applications such as brushes, switches and contact materials for rail systems and other industrial devices. The composite comprises a copper network matrix having a plurality of pores containing graphite. The composite may have an IACS value of at least 40% which may even be higher than 70% and a density value of at least 6.0 g/cm3. The method for preparation of the composite comprises mixing graphite and copper powder under non-oxidising conditions, compacting the mixture and sintering under non-oxidising conditions.

Abstract: A method of manufacturing a separator for a polymer electrolyte fuel cell in which the specific resistance is small, and the coefficient of thermal conductivity and the gas shielding property are high and have high strength. The sintering material comprises a phenol resin coated to the surface of a powder of carbon, and the plate is a metallic plate having plating on both surfaces. After the metallic plate is arranged in a mold provided with grooves, the sintering material is filled to both sides of the metallic plate, and then they are heated and sintered. The separator for a fuel cell becomes homogeneous, and, as a result, the gas shielding property rises with high strength, because phenol resin has been uniformly distributed in the sintering material. Moreover, because oxides are not generated on the surfaces of the separator by sintering, the specific resistance will be relatively small.

Abstract: Flute grinding cemented carbide workpieces with a diamond containing resin bond grinding wheel is improved by restricting the diamond to comprise a silver-coated diamond; conducting the grinding in the presence of a lubricant consisting of only straight oil; and conducting the grinding at a wheel speed of less than about 30 m/s and preferably about 20 m/s. The preferred diamond is coated with about 25% and 75% silver by weight.

Abstract: A high-speed steel article, particularly a cutting tool, produced by powder metallurgy and its production, the steel having a high degree of purity corresponding to a K0 value of no higher than 3 according to DIN 50 602 and being of a particular composition which comprises the elements C, Si, Mn, Cr, W, Mo, V, Co, S and N. Also provided is a process for the high-speed machining of metal parts without lubricants.

Abstract: In accordance with the method according to the present invention, particles consisting of ferrotitanium, ferroniobium or ferrovanadium are dispersed and hot compacted in a metal matrix powder consisting of hardening steel or heat-resistant alloys. In so doing, titanium, niobium or vanadium carbide is obtained in situ by a solid-state reaction, i.e. without melting, from the carbon admixed or contained in the matrix powder and the ferroalloy particles. Carbon can also be absorbed from the gaseous phase and it may be substituted by nitrogen. This method permits a reasonably-priced introduction of hard particles into the composite material, the hard particles having a size that is necessary as a protection against scoring wear.

Abstract: There is disclosed a method of abrading a product where a corrosive environment is experienced which includes the steps of using, as the abrading element, a composite diamond compact comprising a diamond compact bonded to a cemented carbide substrate, the diamond compact comprising a polycrystalline mass of diamond particles and a second phase containing diamond catalyst/solvent and a noble metal.

Abstract: An iron-based sintered powder metal mixture for valve guides, valve seat inserts and other high temperature, high wear applications requiring excellent net-shape stability during sintering comprises a powder metal mixture consisting essentially of 0.5-2.0 wt. % of fine, soluble graphite which goes into solution in the elemental iron matrix, 0.5-2.5 wt. % stable graphite which remains as free graphite in the sintered structure, 0.5-3.0 MoS2, which reacts with 1.0-5.0 wt. % copper to drive a sintering reaction at relatively low sintering temperatures of between 1030—1150° C. The resulting sintered particles have good mechanical strength and wear resistance and possess excellent machineability and dimensional stability.

Abstract: Disclosed is a method of making a composite diamond having a cutting edge comprising a diamond compact bonded to a cemented carbide substrate, the diamond compact having a working surface, an edge of which provides the cutting edge, wherein the diamond compact comprises a first phase containing a polycrystalline mass of diamond particles and a second phase containing a diamond catalyst/solvent and ruthenium, which method includes the steps of providing a cemented carbide substrate, providing a layer of diamond particles on a surface of the substrate, providing a source of diamond catalyst/solvent and ruthenium, wherein the source of the diamond catalyst/solvent and ruthenium is the cemented carbide substrate.

Abstract: A self-grown monopoly compact grit and high pressure, high temperature process for preparing the same. The high pressure, high temperature sintered/synthesized monopoly compact grit is used in various industrial tools such as saw blades, grinding wheels, cutting tools and drill bits. Further, the monopoly compact grit of the present invention is produced from a seed of a mono-crystal of diamond or cubic boron nitride surrounded by either a self-grown crystal layer or an integrally bonded poly-crystalline sintered compact layer. The self-grown crystal layer is a new grown crystal structure where the seed crystal grows into a new phase through a normal diamond or cubic boron nitride synthesis process in the presence of a catalyst metal solvent.

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: Hard particles are provided containing 20 to 70% of Mo, 0.5 to 3% of C, 5 to 40% of Ni, 1 to 20% of Mn, a balance in Fe, and impurities, where % represents percentage by mass, and may further contain at least one of 40% or less of Co, 0.1 to 10% of Cr, and 4% or less of Si. A wear resistant iron-based sintered alloy contains 4 to 30% of Mo, 0.2 to 3% of C, 1 to 20% of Ni, 0.5 to 12% of Mn, a balance in Fe, and impurities, with respect to the total mass of the iron-based sintered alloy as represented by 100%. In the sintered alloy, the base contains 0.2 to 5% of C, 0.1 to 12% of Mn, a balance in Fe, and impurities, with respect to the total mass of the base, and the hard particles contain 20 to 70% of Mo, 0.5 to 3% of C, 5 to 40% of Ni, 1 to 20% of Mn, a balance in Fe, and impurities, with respect to the total mass of the hard particles. The hard particles are dispersed in the base with an area ratio of 0.10 to 0.60. A method to produce a wear resistant sintered alloy of the above composition is also provided.

Abstract: A method of manufacturing a friction member by mixing powders of copper/tin-contained metal, ceramic and graphite, and performing high pressure molding and sintering. This manufacturing method produces a high-performance friction member of copper/tin-contained metal, in which segregation of tin is suppressed. Basically, the friction member manufacturing method includes the steps of: mixing powders of copper/tin-contained metal, ceramic, and graphite with each other to form a powder; molding the mixed powders under a pressure larger than 3 MPa; and sintering a molded object.

Abstract: Prosthetic joints, components for prosthetic joints, superhard bearing and articulation surfaces, diamond bearing and articulation surfaces, substrate surface topographical features, materials for making joints, bearing and articulation surfaces, and methods for manufacturing and finishing the same, and related information are disclosed, including methods for manufacturing a diamond prosthetic joint component.

Abstract: Disclosed are a method for manufacturing cutting blades with a shortened manufacturing process and an apparatus for manufacturing cutting blades with a single manufacturing facility, as well as a cutting blade having cutting segments in which diamond particles are uniformly distributed.

Abstract: A method for forming dresser of chemical mechanical polishing pad, firstly to make a stainless steel bottom seat. Then preparing metal welding powder and organic glue, mixing the aforesaid metal welding powder, organic glue and adequate ratio of water to welding thick liquid and uniformly distributing or pasting it on the aforesaid dresser bottom seat to form the sintering layer. The aforesaid metal welding material includes the active metal with diamond can form metal carbonate. Then using the computer visual inspection system to proceed the diamond powder distribution, uniformly distributing them for 60 to 2500 grains per square centimeter. Proceeding the sintering process to make the friction layer of chemical mechanical polishing pad dresser.

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: A cobalt-chromium-boron-platinum sputtering target alloy having multiple phases. The alloy can include Cr, B, Ta, Nb, C, Mo, Ti, V, W, Zr, Zn, Cu, Hf, O, Si or N. The alloy is prepared by mixing Pt powder with a cobalt-chromium-boron master alloy, ball milling the powders and HIP'ing to densify the powder into the alloy.

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 invention concerns a method of improving the dynamic properties of compacted and sintered products having a density between 6.8 and 7.6 g/cm3, preferably between 7.0 and 7.4 g/cm3. According to this method an iron based powder, graphite and a solid particular lubricant having a vaporizing temperature less the sintering temperature, preferably less than about 800° C. is compacted and sintered and the maximum particle size of the lubricant is selected so that the largest pores of a compacted and sintered product prepared from the composition are equal to or less than the largest pores obtained in a compacted and sintered product prepared from the composition without lubricant. The invention also concerns composition of an iron based powder, graphite and a solid particular lubricant having a vaporizing temperature less the sintering temperature, preferably less than about 800° C. and a maximum particle size less than about 0.

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 superabrasive containing layered composite is provided which comprises a substrate block consisting of either ceramic material and metallic or several metallic materials, and a superabrasive containing body adjacent said substrate block. The superabrasive contains superabrasive particles, and a metallic ingredient which is distributed in the superabrasive containing layer, including a working surface. The superabrasive material may be formed using a compression cell wherein the compression cell comprises a die defined by a vertical wall and a flat closed bottom. Placed in the die, in order from bottom upward, comprises a formed pallet of single body or layers of mixed powder forming a refractory compound, a material mass of a working layer containing diamond particles, a mass of ignition material comprising an SHS composition, and an electrical heating element.

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 powder for sintering to manufacture a diamond tool has an average particle size of less than 8 &mgr;m and a loss of mass by reduction in hydrogen of less than 3% and contains 10-80% Fe, up to 40% Co, up to 60% Ni and up to 15% M. M is present, at least partially, in the oxidized state and representing one or more of the elements Mn, Cr, V., Al, Mo and Ti, the balance being unavoidable impurities. This powder may be sintered at 650-1000° C. to give a matrix having a high hardness.

Abstract: A system for fabricating a free form structure of a composite material including carbon nanotubes. The system includes a discharge assembly and a composite formation device operatively linked with the discharge assembly. The discharge assembly dispenses a fusing agent such as for example a high energy density emission, a laser emission or a particle beam emission. The composite formation device includes a composite generator and an arranger in operative engagement with a composite generator. The composite generator engages with the fusing agent so as to create a composite nodal element. The composite nodal element includes a matrix and a multiplicity of fibers formed of carbon nanotubes dispersed throughout the matrix. The arranger positions one node relative to another to define the free form structure.

Abstract: The present invention provides a composite material having comparatively high thermal conductivity and a small coefficient of thermal expansion, which is low cost and preferable as a heatsink material. A graphite powder and an alloy powder, whose main constituent is Ag and Cu, and including Ti, etc., which is selected from the elements belonging to 4A, 5A and 6A groups, are blended together, and are heated at a higher temperature than the melting point of the alloy in a vacuum state or in a gas atmosphere of He, Ar or hydrogen. A coating layer of metal carbide such as TiC is formed on the surface of the graphite grains, and at the same time, they are transformed into a sintered body. The composite material thus obtained is such that the relative density thereof is 70% or more, thermal conductivity thereof is 220 W/m·K or more at room temperature, and the mean coefficient of thermal expansion from the room temperature to 200° C. is 5 through 15×10−6/°C.

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: 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: 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: 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: The present invention relates to the use of a pre-alloyed powder as a binder in the manufacture of diamond tools by hot sintering. This powder is characterized in that it has an average particle size of less than 10 &mgr;m as measured with the Fisher SSS and loss of mass by reduction in hydrogen of less than 2% as measured according to the standard ISO 4491-2:1989 and in that it contains, in % by weight, up to 40% of cobalt, up to 50% of nickel, from 5 to 80% of iron and from 5 to 80% of copper; the other components in the powder consist of unavoidable impurities.

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: The present invention relates to method of making a cemented carbide insert, comprising a cemented carbide substrate and a coating. The substrate contains WC and cubic carbonitride phase in a binder phase based of Co and/or Ni and has a binder phase enriched surface zone essentially free of cubic phase. The binder phase enriched surface zone prevails over the edge. By sintering in an atmosphere essentially consisting of nitrogen the thickness of the binder phase enriched zone can be controlled.

Abstract: A method of manufacturing a sliding part includes: an injection molding step of injection-molding a compacted member of a molding compound which is a mixture of powder material equivalent to SUS440C, graphite carbon corresponding to an oxygen content of the material, and a binder; a degreasing step of heating the compacted member thus obtained by the injection molding step under a neutral atmospheric condition to remove substantially all of the binder from the compacted member; and a baking step of heating the compacted member which is degreased under a vacuum condition of 0.1333 Pa or less from a room temperature up to 1000° C. to reduce an oxygen content of the compacted member to 0.02% or less by the reaction of C+O→CO, and then heating the compacted member under an argon atmospheric condition of 133.3 to 3999 Pa for two hours after the temperature is increased up to 1250° C.

Abstract: A method of manufacturing a friction member by mixing powders of copper/tin-contained metal, ceramic and graphite, and performing high pressure molding and sintering. This manufacturing method produces a high-performance friction member of copper/tin-contained metal, in which segregation of tin is suppressed. Basically, the friction member manufacturing method includes the steps of: mixing powders of copper/tin-contained metal, ceramic, and graphite with each other to form a powder; molding the mixed powders under a pressure larger than 3 MPa; and sintering a molded object.

Abstract: A heat sink material for use with a semiconductor component having a coefficient of thermal expansion near to that of a semiconductor material and a high thermal conductivity, comprising a plurality of diamond particles, a metal, and a metal carbide, wherein the metal carbide and diamond particles constitute the matrix, and the metal fills the interstices of the matrix is provided. Also disclosed are a method for fabricating the same and a semiconductor package using the same.

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: The invention concerns a method of preparing sintered products having high tensile strength and high impact strength comprising the steps of forming a mixture by mixing an iron powder including 1-4% by weight of Cr, 0.2-0.8% by weight of Mo 0.09-0.3% by weight % of Mn, less than 0.01% of C, less than 0.25% by weight of O, 0-1.2% of graphite, a high temperature lubricant and optionally an organic binder; preparing a heated powder composition by heating the mixture to a temperature above ambient temperature; transferring the heated powder composition to a preheated die; forming a compacted body by compacting the heated powder composition in the die at an elevated temperature; and forming a sintered product by sintering the compacted body at a temperature of at least 1220° C.

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: 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: Machinability is drastically improved while maintaining some degree of hardness in an Fe-based sintered alloy. A good machinability Fe-based sintered alloy has an overall composition of, in percent by weight, at least one element selected from the group consisting of P in an amount of 0.1 to 1.0% and Si in an amount of 2.0 to 3.0%, B in an amount of 0.003 to 0.31%, 0 in an amount of 0.007 to 0.69%, C in an amount of 0.1 to 2.0%, and the balance consisting of Fe and unavoidable impurities, has a matrix hardness ranging from Hv 150 to 250, and has free graphite dispersed therein.

Abstract: The invention relates to a steel having the following alloy composition in weight-%: 1.4-1.6 (C+N), max. 0.6 Mn, max. 1.2 Si, 3.5-4.3 Cr, 1.5-3 Mo, 1.5-3 W, wherein 6<W.sub.eq <9, and W.sub.eq =% W+2.times.% Mo, 3.5-4.5 V, max. 0.3 S, max. 0.3 Cu, max. 1 Co, a total amount of max. 1.0 of Nb+Ta+Ti+Zr+Al, a total amount of 0.5 of other elements, including impurities and accessory elements in normal amounts, balance iron, and with a microstructure substantially consisting of a martensitic matrix and in the matrix 2-15, preferably 5-10 volume-% undissolved hard products having the particle size 0.1-3 .mu.m, said hard products being of MX-type, where M is V and X is C and/or N, wherein 40-60% of the C and N content of the alloy is bound to vanadium as carbides and/or as carbo-nitrides, and a functional amount of hard products precipitated in the martensitic matrix after solution heat treatment of the steel at a temperature between 1000 and 1225.degree. C. and tempering at least twice for at least 0.

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: Metal carbide supported polycrystalline diamond (PCD) compacts having improved abrasion/impact resistance properties and a method for making the same under high temperature/high pressure (HT/HP) processing conditions. The PCD compact is characterized as having a mixture of submicron sized diamond particles and large sized diamond particles.