Abstract: A method for producing a substantially silica-free composition of matter comprising a matrix of MoSi.sub.2 having SiC dispersed therein, the matrix being reinforced with a particulate ductile refractory metal, the method comprising providing a composite of the particulate ductile refractory metal and a substantially silica-free composite mechanical alloy powder comprising MoSi.sub.2 and SiC having a composition in that segment of the ternary diagram of FIG. 1 designated A, and consolidating the composite of particulate ductile refractory metal and mechanical alloy powder; the coefficient of thermal expansion of the MoSi.sub.2 matrix having SiC dispersed therein being substantially equivalent to that of the particulate ductile refractory metal. The composition of matter formed by the method and an article of manufacture comprising the same are also disclosed.

Abstract: A sintered titanium-based carbonitride alloy contains hard constituents based on, in addition to Ti, W and/or Mo, one or more of the metals Zr, Hf, V, Nb, Ta or Cr in 5-30% binder phase based on Cobalt and/or nickel. The content of tungsten and/or molybdenum, preferably molybdenum in the binder phase is >1.5 times higher than in the rim and >3.5 times higher than in the core of adjacent hard constituent grains. The alloy is produced by a particular method.

Abstract: A method for producing a metal composite powder, such as a high alloy metal composite powder, which includes pretreating the alloying components prior to milling with a base iron powder. A short milling time is used, yielding a metal composite powder which exhibits good compactability, microstructure, controllable flow, post-sintering homogeneity, and offers a more economical production method.

Abstract: This invention relates generally to a novel method of preparing self-supporting bodies, and to novel products made thereby. In its more specific aspects, this invention relates to a method of producing self-supporting bodies comprising one or more boron-containing compounds, e.g., a boride or a boride and a carbide, by reactive infiltration of a molten parent metal actinide into (1) a bed or mass containing boron carbide and, optionally, (2) at least one of a boron donor material (i.e., a boron-containing material) and a carbon donor material (i.e., a carbon-containing material), (3) a bed or mass comprising a mixture of a boron donor material and a carbon donor material and, optionally, (4) one or more inert fillers in any of the above masses, to form the body.

Abstract: Self-supporting bodies are produced by reactive infiltration of a parent metal into a boron donor material and a carbon donor material. The reactive infiltration typically results in a composite comprising a boron-containing compound, a carbon-containing compound and residual metal, if desired. The mass to be infiltrated may contain one or more inert fillers admixed with the boron donor material and carbon donor material. The relative amounts of reactants and process conditions may be altered or controlled to yield a body containing a wide ranging varying volume percentage of ceramic, metal, and porosity.

Abstract: Additions of carbon or tantalum ranging between about 0.1 to about 0.15 weight percent are added to an iron-rare earth metal permanent magnet alloy. The permanent magnet alloy contains the magnetic phase consisting of Fe.sub.14 Nd.sub.2 B (or the equivalent) tetragonal crystals, which is primarily based on neodymium and/or praseodymium, iron and boron. The isotropic melt-spun ribbons of the preferred alloy are characterized by generally improved magnetic properties. The anisotropic magnetic bodies formed from these ribbons are hot worked at temperatures substantially lower than the conventional alloy which does not contain the carbon or tantalum additions, with an improvement in magnetic properties observed.

Abstract: The invention relates to a composite hard metal body of hard material, a binder and embedded reinforcing material, as well as to a process for the production of the composite hard metal body by methods of powder metallurgy.In order to create a composite hard metal body with improved toughness under load, improved hardness and a lower fracture susceptibility, the invention proposes to build in monocrystalline, preferably needle-shaped and/or platelet-shaped reinforcing materials, coated with an inert layer with respect to the binder metal phase and consisting of borides and/or carbides, and/or nitrides and/or carbonitrides of the elements of Groups IVa or Va or mixtures thereof and/or coated monocrystalline reinforcing material of SiC, Si.sub.3 N.sub.4, Si.sub.2 N.sub.2 O, Al.sub.2 O.sub.3, ZrO.sub.2, AlN and/or BN.

Abstract: This invention relates generally to a novel method of preparing self-supporting bodies, and to novel products made thereby. In its more specific aspects, this invention relates to a method of producing self-supporting bodies comprising one or more boron-containing compounds, e.g., a boride or a boride and a carbide, by reactive infiltration of a molten parent metal actinide into (1) a bed or mass containing boron carbide and, optionally, (2) at least one of a boron donor material (i.e., a boron-containing material) and a carbon donor material (i.e., a carbon-containing material), (3) a bed or mass comprising a mixture of a boron donor material and a carbon donor material and, optionally, (4) one or more inert fillers in any of the above masses, to form the body.

Abstract: The present invention is a method for densifying powder metallurgical parts to 100% theoretical density. The method comprises applying a high pressure of 0.1-100 MPa during sintering in a high pressure furnace at a temperature before which the liquid phase is formed and maintaining this pressure during the rest of the sintering cycle until the furnace has cooled to almost room temperature. The method achieves rapid, complete closure of the porosity which results in parts with close dimensional tolerances and practically no warpage.

Abstract: A magnesium based metal matrix composite is made from rapidly solidified magnesium alloy powder and SiC particulate using liquid suspension coprocessing or mechanical alloying. The composite is suitable for consolidation into bulk shapes having, in combination, high strength, high stiffness, low density, low coefficient of thermal expansion, and high hardness. The composite is suited for uses in such applications as space and missile guidance and navigation and control system precision components where low density, very high specific stiffness and long term dimensional and environmental stability are principal performance criteria.

Abstract: A cermet alloy having a structure comprising a hard phase and a bonding phase, said hard phase comprising (1) at least one of MC, MN and MCN, wherein M is at least one element selected from Ti, Zr, Hf, Th, V, Nb, Ta, Pa, Cr, Mo, U and W and (2) at least one W-Co-B compound; said bonding phase comprising Co. The cermet has superior toughness and hardness, and can be worked by conventional sintering methods. The invention also includes a method for producing the cermet.

Abstract: A non-magnetic, wear resistant composite of from 10 to 45 volume percent of titanium carbide or tungsten carbide particles bonded in a matrix of a nickel-titanium alloy wherein nickel comprises from 53 to 62 weight percent of the alloy with the remainder being essentially titanium.

Abstract: Disclosed are a high toughness cermet comprising a sintered alloy comprising 75 to 95% by weight of a hard phase of carbide, nitride or carbonitride containing Ti, at least one of W, Mo and Cr, and N and C, and the balance of a binder phase composed mainly of an iron group metal, and inevitable impurities,wherein the content of Ti in said sintered alloy is 35 to 85% by weight calculated on TiN or TiN and TiC, and the contents of W, Mo and Cr are 10 to 40% by weight in total calculated on WC, Mo.sub.2 C and/or Cr.sub.3 C.sub.2,the relative concentration of said binder phase at the 0.01 mm-inner portion from the surface of said sintered alloy is 5 to 50% of the average binder phase concentration of the inner portion, and the relative concentration of said binder phase at the 0.1 mm-inner portion from the surface of said sintered alloy is 70 to 100% of the average binder phase concentration of the inner portion, anda compression stress of 30 kgf/mm.sup.

Abstract: A magnesium based metal matrix composite is made from rapidly solidified magnesium alloy powder and SiC particulate using liquid suspension coprocessing or mechanical alloying. The composite is suitable for consolidation into bulk shapes having, in combination, high strength, high stiffness, low density, low coefficient of thermal expansion, and high hardness. The composite is suited for uses in such applications as space and missile guidance and navigation and control system precision components where low density, very high specific stiffness and long term dimensional and environmental stability are principal performance criteria.

Abstract: According to the present invention there is now provided a method of making a sintered titanium-based carbonitride alloy. According to the method, melt-metallurgical raw materials containing the metallic alloying elements for hard constituent-forming as well as binder phase-forming elements are melted and cast, using no intentional additions of the elements C, N, B and O, to form a pre-alloy which in solidified condition of brittle intermetallic phases with hard constituent-forming and binder phase-forming elements mixed in atomic scale. The pre-alloy is crushed and/or milled to powder with grain size <50 .mu.m. The powder is carbonitrided for simultaneous formation in situ of extremely fine-grained <0.1 .mu.m, hard constituent particles enclosed in their binder phase.

Abstract: An improved temperature stable synthetic polycrystalline diamond (PCD) product includes at least one temperature stable PCD integrally and chemically bonded to a matrix carrier support through a carbide forming layer which is of a thickness of at least about 1 micron, the layer on at least one surface of the PCD is in turn is bonded to the matrix carrier. A wide variety of shapes, sizes and configurations of such products is achieved through relatively low temperature and relatively low pressure processing. Various products of various geometries are described as well as the details of the processing to achieve chemical bonding of the PCD elements in a variety of support matrix carrier materials to form a unitary structure having a temperature stability up to about 1,200 degrees C.

Abstract: A process for producing high-strength, substantially nonporous alloys by means of a three-component mixture, including admixing a first component of one or more low-melting temperature metals or alloys thereof, a second component of one or more high-melting temperature metals or alloys thereof, and a substantially inert third component of one or more refractory compounds, subjecting the mixture to changes in temperature so as to form a mixture capable of being shaped at a temperature well below the melting or decomposition temperature of the highest melting metal and the inert refractory compound.

Abstract: The present invention relates to a method of fabricating various types of bearing materials and the bearing materials produced thereby. The processes of the invention may be used to produce porous self-lubricating bearings, laminated composite bearings (babbitt bearings) and bearings for high temperature application. The processes of the invention involve the use of micro-pyretic synthesis to achieve bearing materials with improved bearing properties, including higher bearing capacity and toughness.

Abstract: A cutting insert of a sintered carbonitride alloy and with a complicated geometry, the insert having improved efficiency. This is obtained by giving the powder non-uniform compaction during pressing of the powder into a press-body so that the ultimate working edges will have a higher relative density than the surrounding, more "supporting" material in the press-body. By these means are often obtained surface defects in the form of cracks because of dissolved strains during the sintering.

Abstract: A wear-resistant compound roll having a shell portion produced by sintering a uniform mixture of alloy powder consisting essentially, by weight, of 1.2-3.5% of C, 2% or less of Si, 2% or less of Mn. 10% or less of Cr, 3-35%, as W+2Mo, of one or two of W and Mo, 1-12% of V, and balance Fe and inevitable impurities, and 1-15%, based on the weight of said alloy powder, of VC powder dispersed therein. This compound roll is produced by (a) uniformly mixing the alloy powder with the VC powder; (b) charging the resulting mixed powder into a metal capsule disposed around a roll core; and (c) after evacuation and sealing, subjecting said mixing powder to a HIP treatment.

Abstract: A copper alloy composite material which comprises a copper alloy matrix and at least one additive selected from solid materials having self-lubricity and wear-resistant materials and uniformly dispersed in the alloy matrix is described. The composite material has improved wear resistance and anti-seizing properties.

Abstract: A method for producing a camshaft having a tubular steel shaft and a sintered cam piece joined to the shaft. The sintered cam piece has iron tetroxide film at its surface. The camshaft is produced by assembling a powder compact to the steel shaft to provide a camshaft assembly, sintering the assembly to provide an integral assembly, correcting bending to the assembly, annealing the assembly, grinding the cam piece and effecting vaporization treatment to the assembly at a temperature lower than the annealing temperature.

Abstract: A wear-resistant compound roll having a shell portion produced by sintering a uniform mixture of alloy powder consisting essentially, by weight, of 1.2-3.5% of C, 2% or less of Si, 2% or less of Mn, 10% or less of Cr, 3-35%, as W+2Mo, of one or two of W and Mo, 1-12% of V, and balance Fe and inevitable impurities, and 1-15%, based on the weight of said alloy powder, of VC powder dispersed therein. This compound roll is produced by (a) uniformly mixing the alloy powder with the VC powder; (b) charging the resulting mixed powder into a metal capsule disposed around a roll core; and (c) after evacuation and sealing, subjecting said mixed powder to a HIP treatment.

Abstract: The invention relates to the powder metallurgy. The invention involves deforming combustion products by extrusion at an extrusion temperature chosen in the range from 0.3T.sub.1 to T.sub.2, wherein T.sub.1 is the melting point of a hard phase of the combustion products and T.sub.2 is the melting point of a binder material in a container (5) made up of vertically extending segments (12) defining spaces (13) with one another and having a die (14) and a heat insulated sizing member (17) the temperature conditions of extrusion being controlled by means of a unit (21) having a temperature pick-up (22) and a member (23) receiving information from the pick-up (22) and sending a command for moving the punch (10).

Abstract: A method for producing metal carbide grade powders which comprises forming a wax mixture consisting essentially of in percent by weight about 5 to about 15 paraffin oil, with the balance being an esterified wax and paraffin, heating the wax mixture to a temperature above the melting point to melt the wax mixture and maintain it in the molten state, forming a powder-wax mixture consisting essentially of metal carbide powder, a binder metal, and the wax mixture while heating to a temperature above the melting point of the wax mixture to maintain the wax mixture in the molten state to result in a uniform distribution of the wax mixture on the carbide and binder metal particles, forming a slurry of the powder-wax mixture and water, attritor milling the slurry at a temperature below the melting point of the wax mixture, and removing water and agglomerating to produce metal carbide grade powder wherein a densified article made therefrom exhibits less linear shrinkage than articles made from carbide grade powder abs

Abstract: An injection moldable ceramic composition is prepared by mixing a sinterable powder, a polyacetal binding agent and silicon carbide whiskers which have been coated with a polyacetal resin.

Abstract: A method for manufacturing a dense cermet article including about 80-95% by volume of a granular hard phase and about 5-20% by volume of a metal binder phase. The hard phase is (a) the hard refractory carbides, nitrides, carbonitrides, oxycarbides, oxynitrides, carboxynitrides, borides, and mixtures thereof of the elements selected from the group consisting of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, and B, or (b) the hard refractory carbides, nitrides, carbonitrides, oxycarbides, oxynitrides, and carboxynitrides, and mixtures thereof of a cubic solid solution of Zr--Ti, Hf--Ti, Hf--Zr, V--Ti, Nb--Ti, Ta--Ti, Mo--Ti, W--Ti, W--Hf, W--Nb, or W--Ta. The binder phase is a combination of Ni and Al having a Ni:Al weight ratio of from about 85:15 to about 88:12, and 0-5% by weight of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Co, B, and/or C. The method involves presintering the hard phase/binder phase mixture in a vacuum or inert atmosphere at about 1475.degree.-1675.degree. C., then HIPing at about 1575.degree.-1675.degree. C.

Abstract: A method for the production of a metallic powder molding material is disclosed which comprises a step of imparting mechanical energy due to at least one of such physical actions as vibration, pulverization, attrition, rolling, shocks, agitation, and mixing a metallic particles in a vessel whose interior is held under vacuumized atmosphere or an atmosphere of inert gas thereby enabling the metallic particles to contact each other and acquire improvement in surface quality and a step of hot molding the metallic particles thereby producing a molding material.

Abstract: Reactive ceramic-metal compositions are described that include a ceramic phase of at least 70 percent by volume, 95 percent of theoretical density and a metal phase that retains its chemical reactivity with the ceramic phase after the composition has been fully densified. The composition may be heat treated after densification to form additional ceramic phases in a controllable manner. Preferred ceramic metal compositions wherein the metal and ceramic components retain reactivity after densification include boron carbide ceramic and Al or Mg metals. The process employed in forming said compositions requires first forming a sintered porous body of the ceramic material followed by contacting with the metal component, which may be in chip or solid bar form. The system is then heated to the melting point of the metal and a pressure of at least 200 MPa is employed such that the porous body is filled with metal and the composition is substantially fully densified.

Abstract: Structural components of at least one intermetallc compound and having complicated contours, are made by the steps of preparing a powder mixture of elemental metal powders including at least one powder of a low melting metal element or component and one powder of a high melting metal element or component that subsequently are to form the intermetallic compound. The powder mixture is then sintered to form a sintered body which is machined to a contour close to the finished contour and to dimensions close to the final dimensions. The so machined and shaped part is enveloped with an envelope of the high melting metal element or component. The enveloped part is subjected to a hot isostatic reaction pressing whereby the intermetallic compound is formed.

Abstract: A method for fabricating a titanium aluminide composite structure consisting of a filamentary material selected from the group consisting of silicon carbide, silicon carbide-coated boron, boron carbide-coated boron, titanium boride-coated silicon carbide and silicon-coated silicon carbide, embedded in an alpha-2 titanium aluminide metal matrix, which comprises the steps of providing a first beta-stabilized Ti.sub.3 Al powder containing a desired quantity of beta stabilizer, providing a second beta-stabilized Ti.sub.3 Al powder containing a sacrificial quantity of beta stabilizer in excess of the desired quantity of beta stabilizer, coating the filamentary material with the second powder, fabricating a preform consisting of the thus-coated filamentary materials surrounded by the first powder, and applying heat and pressure to consolidate the preform.The composite structure fabricated using the method of this invention is characterized by its lack of a denuded zone and absence of fabrication cracking.

Abstract: A heat-resistant aluminum alloy sinter comprises 5 to 12% by weight of Cr, less than 10% by weight of at least one selected from the group consisting of Co, Ni, Mn, Zr, V, Ce, Fe, Ti, Mo, La, Nb, Y and Hf, and the balance of Al containing unavoidable impurities. A silicon carbide fiber is included for reinforcing the sinter in a fiber volume fraction range of 2 to 30%.

Abstract: A complex boride cermet having high strength and high toughness, which comprises a hard phase composed mainly of a boride of (Mo.sub.1-x W.sub.x).sub.2 NiB.sub.2 formed by substituting a part of Mo of Mo.sub.2 NiB.sub.2 by W, and a matrix alloy phase composed mainly of Ni and containing Mo, and a complex boride cermet comprising a hard phase composed mainly of Mo.sub.2 NiB.sub.2 or (Mo.sub.1-x W.sub.x).sub.2 NiB.sub.2 and a matrix of an alloy phase composed mainly of Ni and containing Mo, which is characterized in that carbon or/and nitrogen, and optionally at least one metal selected from the metals of Groups 4B and 5B and Cr, are incorporated to further improve the strength and toughness. Such complex boride cermet has high strength and high toughness and maintains such properties even at elevated temperatures of from 600.degree. to 900.degree. C.

Abstract: Self-supporting bodies are produced by reactive infiltration of a parent metal into a boron carbide material which may contain one or both of a boron donor material and a carbon donor material. The reactive infiltration typically results in a composite comprising a boron-containing compound, a carbon-containing compound and residual metal, if desired. The mass to be infiltrated may contain one or more inert fillers admixed with the boron carbide material, boron-containing compound and/or carbon-containing compound. The relative amounts of reactants and process conditions may be altered or controlled to yield a body containing varying volume percents of ceramic, metal, ratios of one ceramic to another and porosity.

Abstract: An improved ceramic-metal composite comprising a mixture of a ceramic material with a ductile intermetallic alloy, preferably Ni.sub.3 Al.

Abstract: A method for producing metal carbide grade powders suitable for isostatic compaction which comprises combining a binder metal powder with an esterified wax and heating the wax to a temperature above the melting point of the wax to melt the wax and maintain it in the molten state to form a first mixture, with the amount of wax being sufficient to result in a level of wax in the subsequently produced second mixture of no greater than about 1/2% by weight, combining a metal carbide powder component with the first mixture while maintaining the wax in the molten state, forming a slurry of the second mixture and water, attritor milling the slurry at a temperature below the melting point of the wax, and removing water from the resulting attritor milled mixture to form the metal carbide grade powder.

Abstract: A dispersion strengthened copper alloy containing a copper matrix, and dispersion particles dispersed in the copper matrix within a range of 0.5 to 6 vol %. In this alloy, an average diameter of a matrix region where the dispersion particles are not present is 0.3 .mu.m or less, and the total amount of solid solution elements contained in the copper matrix is determined such that, when this amount of the solid solution elements is added to pure copper, the electric conductivity of the matrix is lowered by 5% IACS or less.

Abstract: A surface refined sintered alloy with a burnt surface, comprising 75 to 95% by weight of a hard phase containing Ti, C and N as the essential components and otherwise comprising at least one of Zr, Hf, V, Nb, Ta, Cr, Mo and W and the balance of the alloy comprising a binder phase composed mainly of Co and/or Ni and inevitable impurities, wherein the sintered alloy satisfies at least two conditions selected from the group consisting of the following (1) to (3):(1) the average grain size of the hard phase in a surface layer to the inner portion of 0.05 mm from the burnt surface of the sintered alloy is 0.8 to 1.2-fold of the average grain size of the hard phase in the inner portion of the sintered alloy excluding the surface layer;(2) the average content of the binder phase in the surface layer to the inner portion of 0.05 mm from the burnt surface of the sintered alloy is 0.7 to 1.

Abstract: The proposed invention is used for the manufacture from the obtained composite of cutting tools, hard alloy tooling, dies and other products. A method according to the invention involves preparing a mixture, compacting it, placing the mixture into a synthesis zone, igniting the mixture, with subsequent reaction of components of the mixture under combustion conditions. Then cure is carried out during a period ranging from about 0.1 seconds to about 0.5 hours, and the hot combustion products are compacted under pressure at an average pressure rise rate ranging from about 10 to about 2000 kgf/cm.sup.2.s, with subsequent cure of the compacted product under isobaric conditions to complete homogenization of the composite, with subsequent cooling thereof to obtain an end composite.

Abstract: There are disclosed a high strength nitrogen-containing cermet which comprises 7 to 20% by weight of a binder phase composed mainly of Co and/or Ni, with the balance being a hard phase composed mainly of TiC, TiN and/or Ti(C,N) and inevitable impurities, wherein the hard phase comprises 35 to 59% by weight of Ti, 9 to 29% by weight of W, 0.4 to 3.5% by weight of Mo, 4 to 24% by weight of at least one of Ta, Nb, V and Zr, 5.5 to 9.5% by weight of N and 4.5 to 12% by weight of C; and a process for preparing the same which comprises via the formulating, mixing, drying, molding and sintering steps of Co and/or Ni powder, at least one powder of TiC, Ti(C,N) and TiN, WC powder, Mo and/or Mo.sub.2 C, and at least one powder of carbides of Ta, Nb, V and Zr, wherein the sintering step is carried out by elevating the temperature up to 1350.degree. C. in vacuum, with the nitrogen atmosphere being made 1 torr at 1350.degree. C.

Abstract: In a method of producing a sintered aluminium nickel alloy particles of powder are formed with nickel surfaces (either on nickel or on ceramic material). The surface of the nickel is oxidised and these particles are then mixed with aluminium powder and the mixture sintered in known fashion.

Abstract: A method for improved HIPing of filament reinforced metal matrix composite samples is disclosed. The method departs from conventional HIPing practice in that it does not rely on the heating of the HIPing gas in order to increase pressure. Rather, the temperature of the article and of the HIPing gas is first to the HIPing temperature and the pressure of the gas and the pressure on the sample is then raised to the HIPing pressure. Benefits are derived in that a lower level of filament fracture results.

Abstract: The present invention relates to a method of preparing an alloy for use as a cutting tool material comprising hard principles and binder phase by which a uniform distribution of the hard principles in the binder phase is obtained, and the resulting product.

Abstract: A composite material is disclosed along with the method of making the same. The material comprises a tough grade of cemented carbide granule dispersed with a hard brittle grade of cemented carbide granules to form a matrix. The quantity of hard, brittle cemented carbide granules is between 20% to 60% of the total composition. Such material functions to improve wear resistance without sacrificing toughness.

Abstract: The present invention relates to a method of sintering ceramics and ceramics obtained by said method. According to the present invention, the synthesis and sintering of ceramics can be simultaneously carried out by utilizing the reaction heat generated when at least one metallic element selected from metallic elements of IIb, IVb, Vb and VIb groups of the Periodic Table is combined with at least one nonmetallic element such as B, C N and Si without heat or by preliminarily heating the ceramics at temperatures remarkably lower than the usual sintering temperature ceramics thus-produced are superior in abrasion resistance and corrosion resistance.

Abstract: Substantially dense, void-free ceramic-metal composites are prepared from components characterized by chemical incompatibility and non-wetting behavior. The composites have a final chemistry similar to the starting chemistry and microstructures characterized by ceramic grains similar in size to the starting powder and the presence of metal phase. A method for producing the composites requires forming a homogeneous mixture of ceramic-metal, heating the mixture to a temperature that approximates but is below the temperature at which the metal begins to flow and presssing the mixture at such pressure that compaction and densification of the mixture occurs and an induced temperature spike occurs that exceeds the flowing temperature of the metal such that the mixture is further compacted and densified. The temperature spike and duration thereof remains below that at which significant reaction between metal and ceramic occurs. The method requires pressure of 60-250 kpsi employed at a rate of 5-250 kpsi/second.

Abstract: This invention provides a cermet alloy improved in toughness high-temperature strength and chipping resistance. This cermet alloy consists essentially of 50-95% by weight of a hard phase of a composite carbo-nitride of at least both of W and Ti and, optionally, one or more elements selected from the group consisting of Groups 4a, 5a and 6a elements of the periodic table, the balance being a binding phase, of an Fe family element or elements and inevitable impurities, said composite carbo-nitride has a rim-and-core structure which comprises a core portion of a composite carbo-nitride poor in Ti and nitrogen, surrounded thereon by a rim portion of a composite carbo-nitride rich in Ti and nitrogen. It is preferred that the hard phase consists of 50% by volume or less of TiN or TiCN particles having N.gtoreq.C and forming no rim-and-core structure and the composite carbo-nitride having the rim-and-core structure.

Abstract: High density compacts are made by providing a compactable particulate combination of Class 1 metals selected from at least one of Ag, Cu and Al, with material selected from at least one of CdO, SnO, SnO.sub.2, C, Co, Ni, Fe, Cr, Cr.sub.3 C.sub.2, Cr.sub.7 C.sub.3, W, WC, W.sub.2 C, WB, Mo, Mo.sub.2 C, MoB, Mo.sub.2 B, TiC, TiN, TiB.sub.2, Si, SiC, Si.sub.3 N.sub.4, usually by mixing powders of each, step (1); uniaxially pressing the powders to a density of from 60% to 95%, to provide a compact, step (2); hot densifying the compact at a pressure between 352 kg/cm.sup.2 (5,000 psi) and 3,172 kg/cm.sup.2 (45,000 psi) and at a temperature from 50.degree. C. to 100.degree. C. below the melting point or decomposition point of the lower melting component of the compact, to provide densification of the compact to over 97% of theoretical density; step (3); and cooling the compact, step (4).

Abstract: A process for densifying porous articles comprises providing a non-reactive container with a green article and sufficient solid encapsulating agent selected from the group consisting of tin and the tin-magnesium eutectic to encapsulate the green article when the agent is in the molten state. The temperature is raised sufficiently to melt the agent and to encapsulate the article. The encapsulated article is maintained at a pressure below the infiltrating pressure of the green article while heating the encapsulated article sufficiently to create a surface on the article that is essentially free of porosity and thereafter, the pressure on the encapsulated article is increased while maintaining the article at its sintering temperature for a sufficient time to increase the density of said article to at least about 98% of theoretical.

Abstract: Dense, finely grained composite materials comprising one or more ceramic phase or phase and one or more metallic and/or intermetallic phase or phases are produced by combustion synthesis. Spherical ceramic grains are homogeneously dispersed within the matrix. Methods are provided, which include the step of applying mechanical pressure during or immediately after ignition, by which the microstructures in the resulting composites can be controllably selected.