Abstract: The present invention relates to a method for obtaining a sintered body of carbonitride alloy with titanium as main component which does not have a binder phase layer on the surface after sintering. This is obtained by performing the liquid phase sintering step of the process at 1-80 mbar of CO gas in the sintering atmosphere.

Abstract: A process for making composite materials, namely reinforced Al-metal matrix composites based on either: (I) Al—W intermetallic phase and Al2O3 ceramic whiskers, or (II) Al—Mo intermetallic phase and Al2O3 ceramic whiskers. This process involves the oxidation of aluminum using tungsten oxide in powder form for product I, and that of aluminum and molybdenum oxide in powder form for product II. Product I contains an Al—W intermetallic phase, some sapphire whiskers, and a continuous Al-metal matrix. Product II contains an Al—Mo intermetallic phase, sapphire whiskers, and a continuous Al-metal matrix. The alumina whiskers are formed as a result of two reactions. They are: (i) the oxidation between the pre-mixed Al and the oxide, and (ii) the oxidation of Al with the atmospheric environment in the presence of the oxide, which acts as a catalytic agent for the reaction. These newly invented products are hard, strong and light.

Abstract: A method of imparting high strength, high ductility, and high fracture toughness to a refractory metal alloy workpiece includes: (i) subjecting the workpiece to at least one pass that reduces the initial cross-sectional area of said workpiece, (ii) annealing the workpiece subsequent to the at least one pass, and (iii) subjecting the workpiece to a final working step comprising at least one pass conducted at a temperature between ambient and 300.degree. C., the final working step further reducing the cross-sectional area of the workpiece such that the total reduction in the initial cross-sectional area of the workpiece is approximately 40%-75% and the final cold working is 0.30 to 0.75 of the total reduction in cross-sectional area. The resulting article has a tensile yield strength of approximately 170-200 Ksi, a tensile elongation of approximately 12%-17%, and a Charpy 10 mm Smooth Bar impact toughness of approximately 100 ft.-lb. to 240 ft.-lb.

Abstract: A process for producing a sintered thermoelectric semiconductor includes a first step of forming bulk crystals of a thermoelectric semiconductor and a second step of hot extrusion. The second step includes substeps of placing the bulk crystals in the cavity of a heated extrusion die, pushing the ram into the cavity, thereby compressing and crushing the bulk crystals and turning them into a molten or semi-molten state, and finally extruding the molten or semi-molten crystals, thereby sintering them and forming a sintered thermoelectric semiconductor.

Abstract: A method of imparting high strength, high ductility, and high fracture toughness to a refractory metal alloy workpiece includes: (i) subjecting the workpiece to at least one pass that reduces the initial cross-sectional area of said workpiece, (ii) annealing the workpiece subsequent to the at least one pass, and (iii) subjecting the workpiece to a final working step comprising at least one pass conducted at a temperature between ambient and 300.degree. C., the final working step further reducing the cross-sectional area of the workpiece such that the total reduction in the initial cross-sectional area of the workpiece is approximately 40%-75% and the final cold working is 0.30 to 0.75 of the total reduction in cross-sectional area. The resulting article has a tensile yield strength of approximately 170-200 Ksi, a tensile elongation of approximately 12%-17%, and a Charpy 10 mm Smooth Bar impact toughness of approximately 100 ft.-lb. to 240 ft.-lb.

Abstract: A method of producing Iron-Silicon high density sintered articles of intricate design comprising: (a) the blending of compressible iron or low-carbon steel powder, silicon alloyed iron or silicon powder, or combination of silicon alloyed iron and silicon powder, and lubricant, (b) cold pressing said blended mixture with pressures of less than 50 tsi to form the structure of said article with the density up to 88% of the theoretical value and with uniformly distributed hard powder consisting of silicon and/or silicon alloyed particles among ductile iron powder, (c) low temperature stress relieving heat treatment of said formed article at the temperature range of 360-800.degree. C. followed by a cooling rate of less than 120.degree. C.

Abstract: A homogeneous sintered composite made by press-forming a homogeneous mixture of powders of an agglutinating component, a second component having a melting point higher then the agglutinating component, and an exothermically reactive component to form a compact; heating the compact, then inducing an exothermic reaction of the reactive substance which generates sufficient additional heat to melt the agglutinating component without melting the high melting point component. For electronic microcircuit heat-dissipation applications the agglutinating component is a high thermal conductivity metal, and the high melting point component has a low thermal expansivity, whose proportions are adjusted to match the thermal expansion characteristics of microcircuit material. To reduce porosity, the reacted compact is pressed again while the agglutinating component is still in the liquid phase. For low weight applications the second material has high specific thermal conductivity.

Abstract: The invention relates to bullets having increased frangibility (or which can be easily fragmented) and to materials and processes for the manufacture of such bullets. The bullets of the present invention are typically made from copper or copper alloy powders (including brass, bronze and dispersion strengthened copper) which are pressed and then sintered under conditions so as to obtain bullets with the desired level of frangibility. In preferred embodiments of the invention, the bullets also contain several additives that increase or decrease their frangibility.

Abstract: A method for manufacturing a dense and functionally gradient composite material is provided. The method includes steps of preparing a reactant compact made of composite materials, igniting the reactant compact so that a combustion wave is propagating on the reactant compact, and compressing the reactant compact while the temperature profile of the reactant compact is gradient to obtain the dense and functionally gradient composite material.

Abstract: A titanium-based carbonitride cutting tool insert with superior thermal shock resistance is disclosed. This is accomplished by sintering the material under conditions where the melting process is reversed. The melt forms in the center of the material first and the melting front propagates outwards towards the surface. This leads to minimal porosity and a macroscopic cobalt depletion towards the surface. The cobalt depletion, in turn, leads to a favorable compressive residual stress in the surface zone.

Abstract: This invention relates to a method for producing sintered parts of aluminum or aluminum alloy with improved mechanical properties using batch degassing, die compaction and liquid phase sintering. The batch degassing consists of holding a prealloyed aluminum powder at a temperature of about 350.degree. to about 450.degree. C. in a stainless steel autoclave in which the pressure is reduced to less than 5.times.10.sup.-6 torr. Once the desired pressure is reached the powder is cooled down within the autoclave while still under vacuum. The resulting powder is then compacted at a pressure of 20 to 50 tsi at between room temperature and about 250.degree. C., but preferably at a warm temperature of about 65.degree. C. The final densification is completed by liquid phase sintering in argon atmosphere at 625.degree. C. This method allows the production of sintered compacts characterized by a density close to 97% of theoretical, which makes it possible to eliminate the need for a hot working step.

Abstract: A sintering method for a W--Ni--Mn type heavy alloy, including controlling the deoxidization of tungsten and nickel under an inert atmosphere, changing to a hydrogen atmosphere at above a temperature at which manganese is deoxidized and simultaneously deoxidizing tungsten, nickel and manganese, and sintering by raising the temperature, resulting in the fabrication of a sintered heavy alloy having a 100% relative theoretical density.

Abstract: A high performance W--Cu composite powder which is composed of individual particles having a tungsten phase and a copper phase wherein the tungsten phase substantially encapsulates the copper phase. The tungsten-coated copper composite powder may be pressed and sintered into W--Cu pseudoalloy articles having a homogeneous distribution of W and Cu phases without experiencing copper bleedout or it may be used in ceramic metallization for the electronics industry.

Abstract: There is provided a lead-free projectile, such as a bullet or a ballistic shot, formed by liquid phase sintering or liquid phase bonding of a first particulate having a density greater than lead, a second, ductile, particulate having a melting temperature in excess of 400.degree. C. and a binder having a fluidity temperature that is less than the melting temperature of the second particulate. Unlike solid phase sintering that tends to produce articles having a porosity of about 20%, by volume, liquid phase sintering and liquid phase bonding achieve close to 0% porosity. Reducing the porosity level decreases the amount of high density, first particulate, required to achieve a density close to that of lead. Since the high density particulate tends to be the most expensive component of the projectile, this significantly reduces the cost of the projectile. The reduced porosity also allows for an increase in the amount of the second, ductile, component.

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

Abstract: The invention relates to ZrB.sub.2 /Cu composites, and more specifically to methods of making ZrB.sub.2 /Cu composite electrodes and methods of using ZrB.sub.2 /Cu composite electrodes. ZrB.sub.2 powder is contacted with a polymer and shaped to a desired form. The polymer is vaporized and the ZrB/.sub.2 powder is sintered. The sintered ZrB.sub.2 is contacted with Cu and heated above the melting point of Cu which causes the Cu to infiltrate the ZrB.sub.2, forming the ZrB.sub.2 /Cu composite electrode.

Abstract: Direct Metal Fabrication of metal parts is accomplished with a continuous thermal process in which partial reduction of the "green form" part leaves a thin carbon film that maintains the part's structural integrity. The remaining carbon catalyzes a eutectic reducing element to diffuse throughout the part forming organo-metallic bonds that bind the homogenized metal alloy. Supersolidus liquid phase sintering (SLPS) densities the alloy to provide a final part of parent material quality. The DMF process can be used in magnetographic printing to imprint an image.

Abstract: This invention relates to a method for forming a titanium alloy by powder metallurgy, which comprises the processes of mixing uniformly a powder of titanium or an alloy thereof with a low-melting point metal or alloy powder, injecting the mixture into a press forming die, then press forming them under heating to a temperature near and over the melting point of the low-melting point metal, or to a temperature between the liquidus and the solidus of the low-melting point alloy, or to a temperature near and over the liquidus to obtain the targeted compact, and holding this compact in the pressurized state to cause the molten low-melting point metal or alloy to infiltrate the powder grain boundary of the titanium or alloy thereof, and then sintering the compact thus obtained in an inert atmosphere or a vacuum to diffuse the titanium or alloy thereof and the low-melting point metal or alloy into each other and to make alloys of them.

Abstract: An apparatus for producing a three-dimensional object by successive solidification of layers of a solidifiable material (7) at places corresponding to the respective cross-section of the object by means of radiation is provided whereby the apparatus comprises a support (4) for supporting the object (6) to be formed, a coating device (12) for applying layers of the solidifiable material (7) onto the support (4) or a previously solidified layer, a solidifying device (14) for solidifying the layers of the material (7) at places corresponding to the respective cross-section of the object and a heating apparatus (8) disposed above the support (4) in operational position for heating the solidifiable material (7), the heating apparatus (8) comprising at least one straight radiant heater (81) with a varying heating power along its length.

Abstract: Heatsinks for microcircuit packages are formed by first mold-pressing a composite powder of free-flowing spray-dried particles of copper and at least one other denser material such as tungsten and/or molybdenum breakably agglutinated in nodules grouping sub-nodules of surface alloyed pairs of particles of each metal, the proportions of which are adjusted to match the thermal expansion characteristics of the microcircuit material. The pressed compacts are then heated in a sintering furnace at 1090.degree. C. to 1150.degree. C. in order to effect an homogeneous distribution of the melting copper throughout the structure. The process results in a readily usable component having good thermal conductivity and matched thermal expansion that requires no further machining.

Abstract: A method of making a structural iron-based article comprising: (a) blending a compressible base iron powder (max. particle size of 100 microns) a graphite powder to provide carbon in mixture, and a single master alloy powder (average particle size of 10 microns) meltable within the range of 900.degree.-1200.degree. C. (1690.degree.-2220 .degree.F.) to form a mixture, the master alloy powder being present in an amount of 1-5% by weight of the mixture and consisting of (i) hardenability enhancing alloying ingredients selected from Mn, Mo, Ni, Cr, Cu and Fe, with Fe being present only if Cr or Mo is selected and (ii) wetting agents selected from the group of B, Y, Si and rare earth misch metal, the master alloy being devoid of carbon and being proportioned to provide a desired amount of hardenability in the base powder; (b) compacting the mixture to a green density 7.1-7.4 g/cm.sup.

Abstract: A sub-caliber, spin stabilized multi-purpose projectile (FAPDS) made of a liquid phase sintered heavy metal sintered material composed essentially of metallic tungsten powder with additives of cobalt and nickel. To attain the highest final ballistic performance in lightly armored air and ground targets (e.g. aircraft, helicopters, armored personnel carriers) the present invention provides that the tungsten percentage of the projectile body lies between 90 and 99.5 weight percent, the density of the sintered material lies between 17.5 and 19.2 g/cm.sup.3 and the ratio of cobalt to nickel in the binder phase lies between 1:0.5 and 1:2.3, preferably 1:1.5. The projectile body according to the preferred embodiment of the invention is made of one piece and includes in its front portion a cylindrical pin for fastening of a projectile tip made of heat treatable steel.

Abstract: The present invention relates to modifying the properties of a metal matrix composite body by a post formation process treatment and/or a substantially contiguous modification treatment. The post formation process treatment may be applicable to a variety of metal matrix composite bodies produced by various techniques, and is particularly applicable to modifying the properties of a metal matrix composite body produced by a spontaneous infiltration technique. The substantially contiguous modification process may also be used primarily in conjunction with metal matrix composite bodies produced according to a spontaneous infiltration technique. Particularly, at least a portion of the matrix metal of the metal matrix composite body and/or the filler material of the metal matrix composite body is modified or altered during and/or after the formation process.

Abstract: A method for producing high density and ultrafine W/Cu bulk material by a mechano-chemical process is disclosed. In the method of this invention, metal salts as start materials are spray-dried and prepare W--Cu precursor powder having uniformly-dispersed tungsten and copper components. The W--Cu precursor powder in turn is subjected to a desalting and milling process, thus preparing W--Cu oxide composite powder. Thereafter, the W--Cu oxide composite powder may be formed into a formed green body prior to reducing and sintering under hydrogen atmosphere.

Abstract: A new class of low chop contact materials based on Ag-chromium carbide and Ag--Cr compositions have an essentially 100% dense, porosity free microstructure. These materials combine the advantageous properties of Ag--WC and Cu--Cr contacts without their disadvantages. A method of making this new class of low chop contact materials includes the steps of cold pressing a mixture of Ag and chromium or chromium carbide to form an unsintered blank and the elevated temperature infiltration of silver into the unsintered blank to obtain an essentially 100% dense, porosity free microstructure.

Abstract: An electrical contact material for switching rated currents between 20 and 100 Ampere having improved operational life made of 3.2 to 19.9 wt-% tin oxide and 0.05 to 0.4 wt-%, in each case, of indium oxide and bismuth oxide, the remainder being silver. In the course of the manufacture of the material by powder metallurgy more than 60 wt-% of the tin oxide should exhibit a particle size of more than 1 .mu.m.

Abstract: A method of producing a cutting insert which includes the steps of: providing a generally homogeneous powder blend of powder components; forming the powder blend into a green body wherein the green body includes a rake face and a flank face with a cutting edge at the juncture of the rake face and the flank face; honing the cutting edge of the green body; and consolidating the green body with the honed cutting edge so as to form a consolidated body with a honed cutting edge.

Abstract: A method of free form fabrication of metallic components, typically using computer aided design data, comprises selective laser binding and transient liquid sintering of blended powders. The powder blend includes a base metal alloy, a lower melting temperature alloy, and a polymer binder that constitutes approximately 5-15% of the total blend. A preform part is built up, layer-by-layer, by localized laser melting of the polymer constituent, which rapidly resolidifies to bind the metal particles. The binder is eliminated from the preform part by heating in a vacuum furnace at low atmospheric pressure. The preform part may require support during elimination of the polymer binder and subsequent densification by controlled heat treatment. Densification is performed at a temperature above the melting point of the lower temperature alloy but below the melting point of the base metal alloy to produce transient liquid sintering of the part to near full density with desired shape and dimensional tolerances.

Abstract: A method for fabricating articles of high-temperature aluminum alloys having a compressional strength of at least 20 kg/mm.sup.2 at temperatures of 300.degree. C. or greater, is disclosed. The method comprises the steps of: (a) forming a porous preform from particles of a first aluminum alloy via cold-pressing, the preform having the shape and dimension of the aluminum alloy article to be fabricated; (b) squeeze-casting a molten second aluminum alloy into void spaces of the porous preform to form an aluminum composite containing the first aluminum alloy, which serves as a reinforcement phase, dispersed in the second aluminum alloy, which serves as a matrix phase; (c) wherein the molten second aluminum alloy is cast at such temperatures so as to cause a surface of the first aluminum alloy particles to melt and thereby form a strong bonding with the second aluminum alloy.

Abstract: The invention relates to a method for the fabrication of dimensionally accurate metal pieces by sintering a material which, before the sintering, consists of a blend of three pulverous ingredients, of which the first ingredient is in the main an iron-group metal, the second ingredient is in the main copper and phosphorus, and the third ingredient is an alloy of copper and some other metal. The shape of the piece is produced by layer-by-layer freeform selected area laser sintering, wherein a layer of the said powder blend is spread on a base, those regions of the layer which correspond to this cross-sectional surface of the piece are heated by a laser beam to the sintering temperature. Thereafter further successive powder layers are spread one on top of another, and in each layer in turn those areas which correspond to the cross-sectional surface of the piece in that layer are laser sintered.

Abstract: The invention is directed to a non-vapor phase process for forming a metal/ceramic composite containing a relatively inert metal such as silver, copper, or nickel by the reaction of a reactive metal or metal alloy containing the inert metal, and a sacrificial ceramic preform. The resulting metal/ceramic composite is essentially the same shape and dimensions as the sacrificial ceramic preform, and exhibits improved physical and mechanical properties, including improved corrosion and wear resistance.

Abstract: Disclosed is a manufacturing process of a sintered connecting rod assembly comprising a first member with a projection and a second member with a concavity in which the first member and the second member are mated with each other by engaging the projection with the concavity. A powdered raw material is compacted into a first compact and a second compact for the first and second members, wherein the projection of the first compact has a width slightly larger than the width of the concavity of the second compact. Then the projection of the first compact is engaged with the concavity of the second compact to mate the first compact with the second compact, thereby the projection and the concavity are tightly pressed against each other. After sintering the mated first and second compacts, they are forced to release the projection from the concavity. The die for compacting the raw material has a whole cavity and a removable core for dividing the whole cavity into two cavities.

Abstract: A method of controlling chosen geometries in sintering operations uses an insert in the preform which is to be sintered, which insert can withstand sintering temperatures without distortion, and which will not bond to the preform and thus prevent removal subsequent to sintering. In powder metal sintering, inexpensive ceramic alumina inserts satisfy these criteria. A powdered metal preform is caused to shrink onto a precisely formed ceramic insert, thereby to determine final shape accurately. An insert larger in diameter than that of the uninserted undistorted preform final diameter may be used if potential impact on geometry density is factored into its selection. An insert shape other than that of the preform undistorted final shape may be used to create final geometries different by design than those of the preform.

Abstract: An article essentially consisting of one or more of Ti--Al intermetallic compounds is fabricated so as to have a volume ratio of voids no more than 3.5%, by preparing a mixture of materials selected from a group consisting of Ti, Ti alloys, Al, Al alloys, and Ti--Al compounds, having a composition suitable for forming a desired Ti--Al intermetallic compound, and heating said mixture so that said mixture may be sintered. Typically, the temperature and pressure for the heating or sintering process is appropriately selected so that the desired porosity may be obtained. The mechanical strength of an article according to the present invention is not only improved but is highly predictable, or, in other word, highly reliable. The fabrication costs can be reduced because the fabrication process involves only relatively low temperatures when pressing and heating the work at the same time.

Abstract: The method of the invention is concerned with the manufacture of a molded copper-chromium family metal based alloy article which involves the steps of injection-molding a mixture of copper powder, a chromium family metal powder, an iron family metal powder and a thermoplastic organic binder made up of a polymer binder and low molecular binder in a ratio by volume of 5:1 to 1:1, dewaxing a molded body formed by the injection-molding by heating in a reducing atmosphere, and then sintering the dewaxed molded body at 1,100.degree. to 1,450.degree. C. in a reducing atmosphere. According to this method, molded articles having a high dimensional accuracy and high density can be provided.

Abstract: The present invention provides a process for preparing titanium nitride sintered masses having no residual pores and consisting of TiN solid solution particles and Ni solid solution matrix, in which a granulated powder of the following composition:TiN-pMo.sub.2 C-qC-rNi-sMeCwherein:p is 5 to 20 wt %;q is 0 to 1.5 wt %;r is 15 to 30 wt %;s is 0 to 5 wt %;MeC is one or more carbides selected from VC, WC, TaC and NbC;with the proviso that q and s are not 0 wt % simultaneously;is compacted and sintered. The process according to the present invention can provide sintered TiN cermets of high density and a small grain size.

Abstract: A two layer valve seat insert and a method for its manufacture is described. The method comprises the steps of preparing two powder mixtures; a first powder mixture for forming the valve seat face layer; a second powder mixture for forming the valve seat base layer; sequentially introducing a predetermined quantity of each of said first and said second powder mixtures into a powder compacting die and having an interface therebetween substantially perpendicular to the axis of said die; simultaneously compacting said first and said second powder mixtures to form a green compact having two layers and sintering said green compact, wherein at least one of the chemical composition or the physical characteristics of at least one of said first and said second powder mixtures is adjusted so as to result in said valve seat face layer and said valve seat base layer having substantially the same density after compaction.

Abstract: A compacted, single phase or multiphase composite article. Particles for use in the compacted article are produced by providing a precursor compound containing at least one or at least two metals and a coordinating ligand. The compound is heated to remove the coordinating ligand therefrom and increase the surface area thereof. It may then be reacted so that at least one metal forms a metal-containing compound. The particles may be consolidated to form a compacted article, and for this purpose may be used in combination with graphite or diamonds. The metal-containing compound may be a nonmetallic compound including carbides, nitrides and carbonitrides of a refractory metal, such as tungsten. The metal-containing compound may be dispersed in a metal matrix, such as iron, nickel or cobalt. The dispersed nonmetallic compound particles are no larger than about 0.1 micron in particle size and have a volume fraction greater than about 0.15 within the metal matrix.

Abstract: A method of making an article by joining together at least two porous components is described, the method comprising the steps of making at least two generally tubular PM components to be joined in the axial direction, each component having an axial length less than that of the tubular article; the at least two components both having interconnected porosity and each having at least one mutual mating face; assembling the at least two components together so that the at least one mutual mating faces are in proximity to each other; placing an infiltrant material in the bore of the assembled components; heating the assembled components to melt the infiltrant material and cause it to infiltrate the interconnected porosity at least in the region of the mutual mating faces so as to cause the components to become bonded together by the infiltrant material. Examples of the manufacture of valve guides are given.

Abstract: A method of producing a composite powder by providing particles of (I) tungsten, niobium, zirconium, titanium or mixtures thereof, (II) silicon and (III) carbon in a proportion relative to each other so as to possess an overall chemical composition in that segment of the ternary diagram of FIGS. 2(a), 2(b), 2(c) and 2(d) designated A, and subjecting the particles to a mechanical alloying process under conditions and for a time sufficient to produce the composite powder. Also disclosed is a method of forming a substantially oxygen-free composition of matter comprising a matrix substance of WSi.sub.2, NbSi.sub.2, ZrSi.sub.2, TiSi.sub.2 or alloys thereof having SiC dispersed therein, the method comprising consolidating the above-described composite powder. Also disclosed is a method of forming oxidation- and wear-resistant coatings by subjecting the composite powder whose composition lies in segment A to a metallurgical process such as plasma spraying.

Abstract: A process for preparing an alloy having excellent corrosion resistance and abrasion resistance is provided. The alloy is prepared by providing a powder mixture or VC-powder-containing wire having a matrix metal, including a VC powder having a particle diameter of 10 .mu.m or less, and at least one member selected from the group consisting of an Fe-base alloy, a Co-base alloy and a Ni-base alloy. The powder mixture or VC-powder-containing wire is melted with a heat source having a high energy density. The resultant melt is then cooled to homogeneously crystallize and/or precipitate VC, such that the particle diameter of the VC is reduced to 5 .mu.m or less in the matrix metal phase. Also disclosed is a process for preparing a surface-modified metallic member from a metallic member and an alloy prepared from the aforementioned process.

Abstract: A high density, high strength and high compressive strain tungsten heavy alloy consists essentially of tungsten in the amount of approximately 90% by weight, and the rest Mn and Ni in an amount sufficient to cause sintering at between 1100.degree. and 1400.degree. C. The W--Ni--Mn alloy exhibits characteristics of intense shear bands (which could indicate failure by adiabatic shear during high strain-rate dynamic testing) thus making it an attractive material for kinetic energy penetrators. Moreover, the alloy provides an inexpensive high density material which can be produced in furnaces for conventional ferrous powder metal part manufacturing and other conventional non-ferrous powder metal part manufacturing by lowering the sintering temperature by 200.degree. to 300.degree. C.

Abstract: Composites are grown by contacting pressed aluminum powder forms or metal masses with oxide powder as the oxygen supply source needed for composite growing and then heating, with reaction sintering by a thermite reaction between the oxides and aluminum supplied by capillary action.

Abstract: Heat multilayer aluminum nitride greenware, a composite of layers of aluminum nitride green tape having refractory metal ink patterns deposited thereon, in a nonoxidizing atmosphere, at atmospheric pressure to effect liquid phase sintering of both the aluminum nitride greenware and the refractory metal ink. The resultant cofired structure is substantially free of warpage and has satisfactory thermal conductivity, surface finish, mechanical properties and resistance to delamination.

Abstract: A heat sink composed of thermally conductive particles dispersed in a monolithic structure having a continuous microstructure; and the method of forming a heat sink by molding the heat sink from a thermoplastic or epoxy material which has been filled with thermally conductive particles, debinding the molded heat sink and densifying the debound heat sink into a monolithic structure.

Abstract: An aluminum alloy powder or a green compact thereof is prepared, wherein: (1) the composition formula is Al.sub.100-a-b Fe.sub.a X.sub.b where a and b in atomic % are 4.0.ltoreq.a.ltoreq.6.0, 1.0.ltoreq.b.ltoreq.4.0, and where X is at least one alloy element selected from Y and Mm (mish metal); or (2) the composition formula is Al.sub.100-a-b-c Fe.sub.a Si.sub.b X.sub.c, where a, b and c in atomic % are 3.0.ltoreq.a.ltoreq.6.0, 0.5.ltoreq.b.ltoreq.3.0, and 0.5.ltoreq.c.ltoreq.3.0, and where X is at least one alloy element selected from Ti, Co, Ni, Mn and Cr, and wherein both (1) and (2) include an amorphous phase of at least 1% by volume. The aluminum alloy powder or the green compact thereof is heated at a temperature increasing at a rate of at least 80.degree. C./min. to a predetermined temperature of at least 560.degree. C. and not more than a temperature at which 10% by volume of a liquid phase is contained in the alloy powder or green compact.

Abstract: The disclosure is for a method of bonding materials with severely mismatched coefficients of thermal expansion, such as carbon/carbon and a composite of aluminum oxide and niobium and for the structure of the bonded joint. The key to a good bond between such materials is the use of a thin layer of porous sintered metal as an intermediate material which is bonded to the two diverse thermal expansion materials. The sintered material has a porosity of 20 to 80 percent, and stays bonded to both of the different material surfaces while the sintered material itself is also not destroyed by the thermal stress.

Abstract: A compacted, single phase or multiphase composite article. Particles for use in the compacted article are produced by providing a precursor compound containing at least one or at least two metals and a coordinating ligand. The compound is heated to remove the coordinating ligand therefrom and increase the surface area thereof. It may then be reacted so that at least one metal forms a metal-containing compound. The particles may be consolidated to form a compacted article, and for this purpose may be used in combination with graphite or diamonds. The metal-containing compound may be a nonmetallic compound including carbides, nitrides and carbonitrides of a refractory metal, such as tungsten. The metal-containing compound may be dispersed in a metal matrix, such as iron, nickel or cobalt. The dispersed nonmetallic compound particles are no larger than about 0.1 micron in particle size and have a volume fraction greater than about 0.15 within the metal matrix.

Abstract: A process for forming an electrode assembled into a vacuum interrupter is composed of the steps of blending silver(Ag) powder and chromium(Cr) powder in a content ratio such that Ag powder forms a matrix and Cr powder being dispersed therein, the blending ratio is prefer to be determined to contain 50 to 95 wt. % of Ag powder and 5 to 50 wt. % of Cr powder, compacting the blended powder to a compacted body, sintering the body at temperatures around melting point of Ag, and regulating density of the sintered article at least 90%. Particle size of Cr to be blended may be determined less than 150 .mu.m, more preferably, less than 60 .mu.m. Sintering temperature may be determined between 800.degree. to 950.degree. C.

Abstract: A sintered Al-alloy, which has a composition of 0.2 to 2.0% of Mg, 10.0 to 35.0% of Si, from 0.2 to 4.0% of Cu, and Al and unavoidable impurities in balance, is produced by using a mixture of the main powder (10.0-35.0% of Si, 0.2-2.0% of Cu, and Al and unavoidable impurities in balance) and at least one metal or mother-alloy powder selected from (a)-(i): (a) Mg powder; (b) Al--Mg powder; (c) Al--Cu powder; (d) Al--Mg--Si powder; (e) Al--Cu--Si powder; (f) Al--Mg--Cu powder; (g) Al--Mg--Cu--Si powder; (h) Mg--Cu powder; and, (i) Mg--Cu--Si powder.