Abstract: Fatigue crack growth-resistant articles are made from powder metal or cast and wrought gamma prime precipitation strengthened nickel-base superalloy material, wherein a relatively high predetermined minimum strain rate, .epsilon..sub.min, is employed during hot working at or near the alloy's recrystallization temperature; or alternatively a relatively high strain level, .epsilon..sub.min, is employed during cold or warm working at temperatures below the alloy's recrystallization temperature. The worked articles are characterized by a uniform fine grain size, and grains which coarsen uniformly after heating at the supersolvus solutioning temperature, thereby alleviating non-uniform grain growth within the material.

Abstract: A method for heating metal powder, e.g., iron powder, comprises irradiating the powder with microwaves. The powder may be coated with various materials to enhance the heating effects of the microwave. For example, the powder may be coated with a non-emissive material, such as a ceramic material. The powder may also be coated with a dipole material, such as water or plastic, or a dielectric material.

Abstract: The rapidly solidified aluminum alloy powder is preformed in a cold or warm environment to form a powder compact having a relative density of 75-93%. Then, the preformed compact is heated and degassed in the atmosphere of an inert gas at temperature of 300.degree. C. to 560.degree. C. for 0.25-3 hours. Immediately thereafter, the compact is subjected to hot coining at 300.degree.-560.degree. C. to obtain a solidified compact having pores at a rate of 2-5%. The solidified compact is then subjected to sizing. Since the inorganic gas prevents reaction between the evaporated water and aluminum while preheating the compact, the hot coining can be carried out in a state where solid state diffusion easily occurs. Thus, the powder particles can be bonded together strongly with a single forging. Also, at the end of hot coining, pores remain in the solidified compact at the rate of 2-5%. Utilizing these pores, the compact can be subjected to sizing to improve its dimensional accuracy.

Abstract: A heat sink composed of metal particles dispersed in a binder or a sintered structure in which the binder is removed; and the method of forming a heat sink by molding the heat sink from a thermoplastic or epoxy material which has been filled with metal particles.

Abstract: The friction lining for disk brakes comprises a carrier plate (10) and a block (16) of a compressed friction material secured to the latter, wherein the carrier plate, on the side bearing the block of friction material, is provided with a sinter-fused mounting bed (12) for the block of friction material of individual shaped members (13) forming frictional and positive connections with the block of friction material, in which, prior to the block of friction material is pressed onto the carrier plate (10) with the mounting bed sinter-fused thereupon, a galvanically, thermally or in some other suitable way produced metallic coating (50) is applied to the carrier plate as a corrosion protection.

Abstract: A silver base electrical contact material with superior resistance to arc erosion along with improved wear and welding resistance. The contact material consists essentially of 0.5 to 39.9 wt % of nickel, 0.14 to 7.0 wt % of nickel oxides, and balance silver. The material contains not less than 0.4 wt % of nickel responsible for constituting minute nickel and nickel particles which have a particle size of not more than 1 .mu.m and are dispersed in a silver matrix for strengthening the material to give improved wear and welding resistance. The dispersed minute nickel oxide particles are included to stabilize arcing occurring at the time of opening and closing contacts in such a manner as to anchor one end of an arc substantially at any immediately available point over the entire contact surface as soon as the arcing occurs, thereby preventing the arc end from moving violently across or beyond the contact surface and therefore minimizing arc related damages or arc erosion.

Abstract: Purely powder-metallurgical processes or sinter-impregnation processes are often used to manufacture CuCr contact materials. Here the aim is to obtain the lowest possible residual porosity, which should be <1%. According to the invention, a powder moulding of the components is densified in two stages; the first stage is a sintering process with a densification of the sintered body to a closed porosity, and the second stage is a hot-isostatic pressing operation (HIP), in which the unencased workpieces are taken to a final density amounting to a space occupation of at least 99%. Thus, an economical method of manufacturing high grade material is obtained. It is possible to produce multi-layer contacts or self-adhesive bonds between the sintered body and a solid substrate, e.g. a copper contact bolt.

Abstract: A sintered dense laser block constructed of ceramic metal composition manufactured through sintering, conventional machining and electro discharge machining. A ceramic metal powder and binder are combined and shaped into a laser block. The laser block is then sintered to permit electro-discharge machining. After detailed machining various subsequent firings will yield different dielectric properties for the laser block. Other laser gyro ceramic parts may be manufactured with the method of the invention such as mirror assemblies, cathodes and laser path length controllers. The electro-discharge machining permits the construction of complex ceramic shapes from a slurry of powdered ceramic metal and binder which has been extruded or shaped and then conventional machined. The resulting part is cheaper and easier to make and the electro-discharge machining provides a method of creating very complex shapes in the part.

Abstract: A process for producing a structural member of an amorphous alloy, which includes the steps of subjecting a material formed from an amorphous alloy having a glass transition temperature Tg and a crystallization temperature Tx, which is higher than the glass transition temperature Tg, to a thermal treatment in which the material is kept at a heating temperature equal to or lower than the glass transition temperature Tg, thereby generating a structure relaxation phenomenon in the material, and subjecting the material to a hot plastic working while setting the hot working start temperature of the green compact at a level equal to or lower than the crystallization temperature Tx. In this process, the workability of the material can be improved to produce a high strength amorphous alloy structural member that has an increased volume fraction of an amorphous phase. Furthermore the generation of any defect due to gas inclusion is suppressed.

Abstract: The present invention relates to a manufacturing process for ring-shaped parts having high wear resistance and mechanical strength. Raw material powder containing (weight %) C at 0.4-0.9%, Ni at 1.5-4.0%, Mo 0.2-0.6%, and a remainder consisting of Fe and unavoidable impurities, is compacted and shaped, thereafter sintered and forged; obtained sintered body is hardened by heating at a temperature within a range of 800.degree.-950.degree. C., thereafter high temperature tempering is carried out for 20-60 minutes at a temperature within a range of 570.degree.-700.degree. C.; then the surface layer of the inner periphery and/or outer periphery of said sintering body is heated; then if required, low temperature tempering (temper process) is carried out at a temperature within a range of 160.degree.-220.degree. C.

Abstract: This invention relates to a process for producing a rare earth-containing powder comprising crushing a rare earth-containing alloy in a passivating gas at a temperature from ambient temperature to a temperature below the phase transformation temperature of the material.Additionally, this invention relates to a process for producing a rare earth-containing powder compact comprising crushing a rare earth-containing alloy in water, compacting the crushed alloy material, drying the compacted alloy material at a temperature below the phase transformation temperature of the material, and treating the compacted alloy material with a passivating gas at a temperature from ambient temperature to a temperature below the phase transformation temperature of the material.Rare earth-containing alloys suitable for use in producing magnets utilizing the powder metallurgy technique, such as Nd-Fe-B and Sm-Co alloys, can be used.

Abstract: A Fe-base sintered alloy for a valve seat for use in internal combustion engines, which constitutes a chemical composition of 0.4 to 2% of C, 0.5 to 5% of Cr, 5 to 15% of Mo, 0.2 to 2% of Ni, 0.4 to 2% of Co, 8 to 20% of Cu, 0.01 to 0.5% of S, and the balance Fe, wherein percentages are by weight. The Fe-base sintered alloy possesses high strength and high rigidity, and hence exhibits excellent abrasive and corrosion wear resistance properties, as well as excellent lubricity.

Abstract: A porous metal block for selectively removing solder or braze from a substrate is disclosed. The block comprises a plurality of protrusions which absorb solder or braze through capillary action. The number and dimensions of the protrusions vary depending on the application. Also disclosed is a process for making such a block involving a unique two steps sintering process.

Abstract: This patent covers the concept of putting a previously sintered carbide tool or part back through the sintering process. This resintering, heals stress related microcracks which, when allowed to progress, could ultimately be a cause of the failure for the object. This produces a longer life, better quality cemented carbide tool to be used for cyclically applying pressure and/or heat.

Abstract: A process for the powder-metallurgical production of a workpiece by filling a binder-free and solvent-free, dry metal powder or ceramic powder into a mold, precompacting the powder by tapping and presintering it for 1/2 hour to 1 hour at 0.65 to 0.85 times the absolute melting temperature without significant shrinkage, adjacent powder particles being joined merely at their contact points by necking to give a skeletal formed body. The formed body is taken out of the mold and finish-sintered at at least 0.9 times the absolute melting temperature for at least 1 hour without additional support by a mold. Advantageously, the sintered body is additionally hot-isostatically pressed containerless in order to reach at least 98% of the theoretical density.

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: A consolidated tungsten alloy body consisting essentially of from about 88% to about 98% by weight of tungsten, balance, nickel and iron, produced by liquid phase sintering, containing a continuous phase of a tungsten, nickel and iron alloy and a discontinuous phase of elongated grains of tungsten having an aspect ratio of at least 4:1 relatively uniformly distributed throughout the continuous phase and wherein said body has a recrystallization temperature of from about 1000.degree. C. to about 1200.degree. C. A process for producing the consolidated bodies comprises working and annealing at controlled temperatures to achieve the desired properties. The working temperatures are from about 700.degree. C. to about 900.degree. C. and the annealing temperature is preferably 1200.degree. C.

Abstract: In a method of manufacturing a sintered ceramic material using the heat generated in a thermit reaction as a heating source, a pre-heating is applied preceding to the sintering step or a mixture comprising: (A) at least one ceramic powder, (B) at least one non-metallic powder selected from the group consisting of carbon, boron and silicon, and (C) a metal powder and/or a non-metallic powder other than the above-mentioned (B) is used. Homogeneous and dense sintered ceramic material or sintered composite ceramic material can be obtained by this method, and the fine texture thereof, and the phase constitution, the phase distribution and the like of the composite ceramic phase can be controlled sufficiently.

Abstract: A method for manufacturing a brake fitting comprising a plurality of studs each surrounded by a less fragile belt, the studs being non-contiguously secured to a metal support. According to the method, the support is provided with a slip-resistant surface by coating with a braze welding suspension which is oxidized and reduced. Stud blanks then are molded and compacted from powdered friction products and belt blanks are molded and compacted from metal powders and given an internal diameter 1.005 to 1.05 times the external diameter of the stud blanks, and the belt blanks are disposed around the stud blanks and sintered, obtaining sheathed stud blanks which are placed on the slip resistant surface of the support, and welded thereto by heat treatment. Finally, the sheathed stud blanks are forged at over 400 degree C., shortening them by at least 15%.

Abstract: This invention relates to a process for producing a rare earth-containing material capable of being formed into a permanent magnet comprising crushing a rare earth-containing alloy and treating the alloy with a passivating gas at a temperature below the phase transformation temperature of the alloy. This invention further relates to a process for producing a rare earth-containing powder comprising crushing a rare earth-containing alloy in a passivating gas at a temperature from ambient temperature to a temperature below the phase transformation temperature of the material. This invention also relates to a process for producing a rare earth-containing powder comprising crushing a rare earth-containing alloy in water, drying the crushed alloy material at a temperature below the phase transformation temperature of the material, and treating the crushed alloy material with a passivating gas at a temperature from the ambient temperature to a temperature below the phase transformation temperature of the material.

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: Methods for preparing sintered components from iron-containing and alloy steel powder are provided. The methods includes compacting a powder mixture in a die set at a pressure of at least about 25 tsi to produce a green compact which is then presintered at a temperature of about 1100.degree.-1600.degree. F. (593.degree.-870.degree. C.) for at least about 5 minutes to produce a presintered preform. The presintered preform is then compacted at a pressure of at least about 25 tsi to produce a double-pressed presintered preform, which is, in turn, sintered at a temperature of at least about 1000.degree. C. for at least about 5 minutes to produce a sintered component having improved transverse rupture strength and a higher density.

Abstract: A sintered metallic light-weight structural material consists of spherical voids and lattice-type webs of intermetallic compounds. Owing to its weight-specific strength, which is superior to that of conventional super-alloys, this material is suited especially for application in aircraft and turbine engine construction.

Abstract: A method of preparing a compound pipe, the wall of which comprises an inner layer of a first material and an outer layer of a second material. Powders of the two materials are isostatically hot pressed to form a cylindrical tubular blank in which the first material forms an inner layer and the second material forms an outer layer, the blank after heating to a suitable temperature being extruded over a mandrel.

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 method of manufacturing a sintered machine part, by which the machine part can be manufactured to be sufficiently strong, wear and abrasion resistive, and durable against the fatigue caused by recursive impacts, without the heat treatments. In the method, a machine part composed of 0.1 to 0.8% of carbon by weight, 2 to 6% of nickel by weight, 0.6 to 1.6% of molybdenum by weight, 1 to 3% of copper by weight and balance iron is manufactured by mixing partially diffused alloy powder composed of 2 to 6% of nickel by weight, 0.4 to 0.6% of molybdenum by weight, 1 to 3% of copper by weight and balance iron with graphite powder amounting to 0.1 to 0.8% by weight and molybdenum simple powder having 2 to 7 .mu.m mean particle size amounting to 0.2 to 1% by weight, and then by compacting the mixed powder and sintering the compact.

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: In the method of invention, the formability is imparted to the slurry of a metal or ceramic powder by employing a porous mold and removing the dispersion medium through the evaporation or thermal decomposition thereof, or by using a silazane oil as the dispersion medium and curing it by heating. Since the phase change usually accompanying volume change does not occur in the dispersion medium, strain and deformation rarely occur in the molded body. As result, the sintered body obtained has high dimensional accuracy.

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: A tungsten carbide powder and cemented tungsten carbide article made from the powder are disclosed. The powder has a particle size of greater than 20 micrometers in diameter and no particles less than one-half the average particle size or greater than two and one-half times the average particle size.

Abstract: A superplastic composite material is produced by thoroughly and homogeneously mixing particles or whiskers of silicon nitride and aluminum metal powder in a solvent, then removing the solvent from the resultant mixture, sintering the residual mixture at an elevated temperature, further compressing it at an elevated temperature, then hot extrusion-molding the compressed mixture thereby forming a shaped article, and heat-treating this shaped article.

Abstract: The cathode-forming method involves incorporating cobalt into a nickel plaque so that the exposed surfaces and the pores of the nickel plaque are uniformly covered with cobalt. The plaque is then treated to form nickel hydroxide in the pores and on the surfaces thereof. The cobalt is thus diposed at the interfacial boundary of the nickel plaque and nickel hydroxide so as to reduce the impedance and enhance charge conduction of the cathode. The mode of incorporation can vary. Thus, the sintered nickel plaque can be soaked in an aqueous solution of a water-soluble salt of cobalt, such as cobalt nitrate, then dried and resintered. Another mode involves dispersing a water-soluble cobalt salt in an aqueous slurry of nickel particles and water-soluble binder for the particles. The nickel particles are thus uniformly covered with the dissolved cobalt salt and then are compacted into a plaque. The plaque is dried and finally sintered.

Abstract: A method for producing an anisotropic rare earth magnet is improved by applying compressing stress on a free surface of an compacted material at the time of extruding the compacted material in order to prevent forming cracks, and improved by using a double action punch provided with a core punch and a sleeve punch so as to mold a compacted material and extrude the compacted material into the anisotropic magnet material in a single heat process continuously.

Abstract: The invention relates to heavy tungsten-nickel-iron alloys with high mechanical characteristics and a specific gravity between 15.6 and 18. The alloys include a tungsten .alpha.-phase in the shape of butterfly wings with dislocation cells of dimensions between 0.1 and 1 .mu.m, and a nickel-iron bonding .gamma.-phase having a mean free path of less than 15 .mu.m and an Ni/Fe ratio greater than or equal to 2.

Abstract: A high melting metal silicide sputtering target which comprises a fine texture whose stoichiometric composition grains of MSi.sub.2, where M represents a high melting metal, have a maximum grain size of 20 .mu.m, whose free silicon grains have a maximum grain size of 50 .mu.m and whose oxygen content is not more than 200 ppm and has a density ratio to the theoretical density of 99% or more has good film characteristics including the reduction in the number of grains formed on the sputtered film and is useful as an electrode material or a wiring material in semi-conductor devices.

Abstract: The invention is related to a bearing material having multiple layers therein and a method for manufacturing the same. The invention features that a bearing layer consisting mainly of an integrated resin powder is formed on a porous layer covering a back metal, such as a steel plate of like, that the integrated resin powder consists of P T F E resin precipitate and F E P resin precipitate and/or P F A resin precipitate and that each particle of the integrated resin powder is covered with Pb-Sn alloy powders.Accordingly, the integrated resin powder independently provides a predetermined lubricating property. In addition, since these resin precipitates are in unity, it is possible to maintain excellent cavitation resistance property and load resistance property, even under severe boundary conditions.Furthermore, since each of the integrated resin powder is covered with the Pb-Sn alloy powder, an uniform and deep penetration of the alloy powder into pores of the porous layer can be easily obtained.

Abstract: A carefully controlled amount of hydrogen is diffused into titanium or its alloys at an elevated temperature above the transformation temperature. After the elevated temperature is maintained for an approprate duration of time, eutectoid transformation is performed in an inert atmosphere, again for an appropriate period of time, during which or alternatively after which the hydrogen is removed and the metal cooled to room temperature. A sintered titanium alloy component of the type intended for use as a joint replacement subjected to such a treatment displays a fatigue strength which is noticeably improved over a similar article with an equiaxed or lamellar microstructure.

Abstract: The present invention provides a dewaxing process for metal powder compact which comprises the steps of embeding in alumina powder an injection-molded metal powder compact consisting of metal powder and an organic binder including low melting point substances; heating the embeded compact to a temperature of 200.degree. C. in a chemically inert atmosphere in a dewaxing furnace, thereby removing the low melting point substances from the compact without deformation of the compact; placing the compact in a closed sintering vessel so as to keep the surrounding temperature constant and disposing the vessel in a vacuum furnace; evacuating the vacuum furnace; and removing the organic binder by heating to a temperature of 550.degree. to 650.degree. C. at a heating rate of 300.degree. to 600.degree. C./hr while supplying an inert gas into the vacuum furnace.

Abstract: A method for fabricating a superconductive film composed of a RE.sub.1 Ba.sub.2 Cu.sub.3 O.sub.x compound, or a (Bi.Sr.Ca.Cu.O) compound. In a first embodiment, oxides or carbonates of the component materials, namely Y.sub.2 O.sub.3, BaCO.sub.3, and CuO are mixed in atomic ratios of 1:2:3, according to the chemical formula of RE.sub.1 Ba.sub.2 Cu.sub.3 O.sub.x, and sintered to create a rhombic perovskite structure. The sintered mixture is powdered again, with added powdered amounts of Y.sub.2 O.sub.3 and powdered metallic Cu, and sintered. The sintered product is used as the source for an electron beam evaporator. In a second embodiment the (Bi.Sr.Ca.Cu.O) compound is formed into a sintered pellet which is composed of a mixture of one part of BiO, 3-15 parts of SrCO.sub.3, 4-30 parts of CaCO.sub.3, and 2-5 parts of CuO, in atomic ratios of Bi, Sr, Ca and Cu.

Abstract: Metallic sintered parts with hollow structure and high density and toughness can be produced easily be kneading a raw metallic powder with an aqueous solution of an organic binder, extruding the resulting kneaded mixture, removing the organic binder from the extruded product and sintering the binder removed extruded product.

Abstract: A long life high current density cathode is made from a mixture of tungsten nd iridium powders by processing the mixture of powders with an activator into a porus billet, and then impregnating the billet with a mixture of barium peroxide and a coated emitter by firing the billet in a dry hydrogen furnace at a temperature at which the impregnant melts.

Abstract: This invention concerns a heat treatment method for rare earth type permanent magnets which are primarily of the Nd-Fe-B type. With regard to these permanent magnets, which oxidize rather easily in the air, the alloy is crushed, and either compression formed in a magnetic a non-magnetic field, sintered at 900.degree. to 1,200.degree. C., and then machined into the shape desired, and then solution treated in an atmosphere of oxygen and/or nitrogen at a temperature of 900.degree. to 1,200.degree. C., and then aged at 300.degree. to 900.degree. C. in order that an oxide and/or nitride protective layer of 0.001 to 10 .mu. be formed on the surface of the permanent magnet to prevent corrosion and in order to relieve machining strain.

Abstract: A cathode is made from a mixture of tungsten and iridium powders using a ction product formed from reacting barium peroxide with an excess of tungsten as the impregnant.

Abstract: Structural component made of powder metallurgical materials, particularly temperature resistant alloys, nickel base alloys, are produced by injection molding or pressing. The sintering is divided into individual work steps for producing dense and smooth structural components which are true to shape.

Abstract: A wear-resistant sintered iron-based alloy and a process for producing the alloy are described, wherein the alloy comprises a first phase having a martensite composition which comprises from 0.5 to 3.0 wt % of Cr, from 0.4 to 1.0 wt % of Mn, from 0.1 to 0.4 wt % of Mo, and the balance of Fe, based on the total amount of said first phase; a second phase having a martensite and Cr carbide composition which comprises from 10 to 20 wt % of Cr and the balance of Fe, based on the total amount of said second phase; and from 1.0 to 2.5 wt % of C, based on the total amount of said alloy; wherein said first phase and said second phase are present as a mixture containing from 10 to 80% by volume of said second phase, based on the total volume of said alloy; and said alloy is substantially free from any residual austenite.

Abstract: This invention relates to substantially full-dense, near-net shape bodies made of dispersion strengthened copper (D.S.C.) powder and products which are cold formed and/or machined from these bodies, such as resistance welding electrodes. The invention includes processes for manufacturing substantially full-dense, near-net shape, substantially equiaxed bodies from D.S.C. powder.

Abstract: A starting material for injection molding of a metal powder including from 38 to 46% by volume of an organic binder and the balance of spherical iron powder with an average particle size from 2 to 6.5 .mu.m and having high density sinterability at low sintering temperature, and a method of producing a sintered parts by conducting injection molding, debinding and sintering using the above-mentioned starting material in a non-oxidizing atmosphere at a temperature lower than the A.sub.3 transformation point.

Abstract: The invention provides an aluminum base bearing alloy which is excellent in both lubricating capability and fatigue resistance and is useful, e.g. in automotive engines. The bearing alloy consists essentially of at least one lubricating element such as Pb and/or Sn the total amount of which is more than 0.04 and not more than 0.07 by sectional area ratio to the aluminum matrix, Si the amount of which is in the range from 0.01 to 0.17 by sectional area ratio to the aluminum matrix, 0.2-5.0 wt % of at least one reinforcing element such as Cu and/or Cr, 0-3.0 wt % of at least one refining element such as Ti and/or B and the balance of Al. The grain size of the lubricating element(s) is not larger than 8 .mu.m, and the grain size of Si is not larger than 12 .mu.m and preferably not smaller than 6 .mu.m.

Abstract: Contact materials based on AgSnO.sub.2 and having Bi.sub.2 O.sub.3 and CuO as further metal oxide additives were previously disclosed. In these materials the total content of all metal oxides was supposed to be between 10 and 25% by volume with the SnO.sub.2 share equal to or greater than 70% by volume of the total amount of oxide.According to this invention the quantity of SnO.sub.2 is kept smaller than 70% by volume; specifically at about 65%, but in any case equal to or greater than 50%. The SnO.sub.2 weight content is to be in the 4% to 8% range and the weight percentage ratio of SnO.sub.2 to CuO is to be between 8:1 and 12:1.In the associated production process, either Bi.sub.2 O.sub.3 powder is purposely admixed to an internally oxidized alloy powder (IOAP) in an additional operation, a grain restructuring with locally different Bi.sub.2 O.sub.3 concentrations occurring in the structure after sintering and compacting.

Abstract: Cemented carbide substrates having substantially A or B type porosity and a binder enriched layer near its surface are described. A refractory oxide, nitride, boride, and/or carbide coating is deposited on the binder enriched surface of the substrate. Binder enrichment is achieved by incorporating Group IVB or VB transition elements. These elements can be added as the metal, the metal hydride, nitride or carbonitride.