Abstract: A solid particle erosion resistant coating includes angular titanium carbide particles uniformly dispersed through a high chromium iron matrix. In one form, the aggregate comprises, by weight, about 30-50% TiC, about 10-30% Cr, about 1.5-5% C and the balance essentially iron in the form of ferrite. The matrix also includes metallurgically identifiable amounts of high chromium content M.sub.7 C.sub.3 carbides therethrough. The coating does not exhibit austenitic or martensitic structure therehthough. A powder alloy consolidated body also includes a surface adjacent region having a similar TiC and high chromium iron matrix. Further, a method for obtaining the coating includes heating above the austenitization temperature of the matrix alloy and below the melting temperature of iron, and cooling the aggregate so as to attain iron in the form of ferrite in the matrix.

Abstract: A method for producing a sintered ferrous alloy containing at least one alloying element whose standard free energy for oxide formation at 1,000.degree. C. is 11,000 cal/g mol O.sub.2 or less is described. The method comprises a sintering procedure comprising steps of elevating the temperature of a green compact comprising said at least one alloying element, sintering it in a sintering furnace and cooling it, wherein the pressure in the sintering furnace is maintained at between about 0.2 and 500 Torr by supplying a reducing gas during at least a part of the sintering procedure under reduced pressure.

Abstract: The invention relates to a process for the production of porous products of boron or boron compounds.This process comprises the following stages:(1) suspending the boron powder in a solution of an alkali metal salt, hydroxide and/or oxide,(2) then separating the powder from the suspension liquid by settling,(3) drying the thus separated powder to obtain an agglomerated powder, and(4) subjecting the thus obtained agglomerated powder to at least two heat treatments performed at different temperatures, the final stage of the heat treatment being performed at a temperature of 1500.degree. to 2200.degree. C. and the first stage being performed at a temperature below that of the final stage.The heat treatment can be performed in three stages, as shown in the attached graph.

Abstract: An improvement is disclosed in a method for producing a metal article of high density comprising pressing a metal powder at a sufficient pressure to form a green article and sintering said green article at a sufficient temperature for a sufficient time to form a sintered article, the improvement being pressing the sintered article at a sufficient temperature for a sufficient time at a sufficient pressure of a non-oxidizing atmosphere to produce the final high density article.

Abstract: A method for making an aluminum nitride powder comprises atomizing a molten aluminum into a nitriding atmosphere of N.sub.2 gas of elevated temperature and solidifying the finely divided liquid particles of aluminum which have been nitrided.

Abstract: A cermet is produced by providing a bulk reaction mixture of particulate reactants plus elemental metal, which reaction mixture is in admixture with a ceramic diluent that is the same as ceramic material formed during sintering of the reaction mixture. Sintering produces a boride-oxide ceramic with the oxide being a metal oxide of the elemental metal. However, the elemental metal is present in the reaction mixture in substantial excess over that amount stoichiometrically required. Sintering is conducted under inert atmosphere, generally after pressing. The invention is particularly directed to boride-based ceramics containing aluminum, which materials are suitable as components of electrolytic cells for the production of aluminum by molten salt electrolysis.

Abstract: A composition for fixing a metal powder molding at sintering, which is used, in the case of disposing a metal powder molding formed by rolling a mixture of a metal powder and a synthetic resin-based binder on a metal base material and sintering the metal powder molding in a non-oxidizing atmosphere, by interposing between the metal powder molding and the base material, comprising a thermosetting resin composition containing a thermosetting resin as the essential component, the amount of the residual carbon of which after the completion of sintering is at least about 0.5% by weight.

Abstract: Disclosed is a decorative silver-colored sintered alloy comprising TiC, Cr.sub.3 C.sub.2 and Ni in amounts of 50 to 98% by weight, 1 to 20% by weight and 1 to 30% by weight, respectively, based on the three components. In this sintered alloy, TiC is present in the form of the dispersed phase of particles and Cr.sub.3 C.sub.2 and Ni are present in the form of a solid solution as the binder phase. This sintered alloy is excellent in the corrosion resistance and is capable of manifesting a mirror surface having a deep silver color.

Abstract: A solid electrolytic capacitor is made with an Aluminum-titanium body. Aluminum and titanium powders are press-molded into a body which is then heated sufficiently to provide a porous Al-Ti alloy with an oxide layer. Next, the body is heated in an atmosphere containing at least 0.1% by volume of oxygen at a temperature in the range of about 500.degree.-700.degree. C. Thereafter, a layer of manganese dioxide is formed over the oxide layer and a cathode electrode layer is then formed over the manganese dioxide layer.

Abstract: A copper-rich metal shape is produced by forming a coherent forerunner shape consisting essentially of cupreous powder, said powder containing a proportion of copper oxide sufficient for facilitating the obtaining of a high sinter density in sintered porous mass, and in a reducing atmosphere at temperature that will sinter copper present, converting said forerunner shape into a porous sintered mass virtually devoid of copper oxide. Said porous mass can be worked so virtually full density if desired.

Abstract: Composite cermets having a central core of a first cermet composition and one or more surrounding layers of different cermet compositions are formed by a multi-step pressing operation, followed by sintering. A tungsten/alumina or molybdenum/alumina composite cermet is useful as an end closure for alumina arc tubes of metal halide discharge lamps.

Abstract: A method of producing metallic strip containing discrete particles of one or more additional metallic or non-metallic materials dispersed therein, includes the step of forming a homogeneous mix of ductile metallic particles and a minor proportion of metallic and/or non-metallic particles having chemical and/or physical properties different from those of the ductile metallic particles. A slurry coating comprising a suspension of the mixed particles in a film forming cellulose derivative is deposited onto a moving support surface, dried and removed from the support surface before being subjected to rolling to effect compaction of the ductile content of the strip and sintering at a temperature at which the metallic particles coalesce to form a matrix containing particles of the additional metallic or non-metallic material(s) which either remain as discrete particles or alloy with the matrix.

Abstract: A magnetic powder core, suitable for use in a low frequency power device, is prepared by a method including the steps of coating an atomized iron powder from an aqueous solution of potassium dichromate, drying the powder, compressing the powder to form a compact and heat treating the compact until it becomes partially sintered. Cores having coercivities below 240.sup.A /m, saturation inductions exceeding 1.3 Tesla and resistivities exceeding 500 microhm cm are disclosed.

Abstract: A powder metallurgical method is described for producing precision components of sintered steel having high strength and high ductility by compressing a powder to form a green compact and sintering the latter at a temperature from 950.degree. to 1250.degree. C. for 5 to 90 minutes in a reducing atmosphere of partially combusted hydrocarbons, sufficient carbon being present to impart a carbon content of 0.05 to 0.6% by weight in the sintered steel; said powder consisting essentially of iron powder containing 0.65 to 0.8% phosphorus, 0.1 to 0.5% graphite or carbon powder, and 0 to 1.5% of a solid lubricant.

Abstract: Permanent magnetic materials of the Fe-B-R type are produced by:preparing an metallic powder having a mean particle size of 0.3-80 microns and a composition of, by atomic percent, 8-30% R (rare earth elements), 2-28% B, and the balance Fe, compacting, sintering at a temperature of 900-1200 degrees C., and aging at a temperature ranging from 350 degrees C. to the temperature for sintering. Co and additional elements M (Ti, Ni, Bi, V, Nb, Ta, Cr, Mo, W, Mn, Al, Sb, Ge, Sn, Zr, Hf) may be present.

Abstract: Permanent magnet materials of the Fe-B-R type are produced by:preparing a metallic powder having a mean particle size of 0.3-80 microns and a composition of 8-30 at % R, 2-28 at % B, and the balance Fe,compacting, andsintering, at a temperature of 900-1200 degrees C.Co up to 50 at % may be present. Additional elements M (Ti, Ni, Bi, V, Nb, Ta, Cr, Mo, W, Mn, Al, Sb, Ge, Sn, Zr, Hf) may be present. The process is applicable for anisotropic and isotropic magnet materials.

Abstract: A process for forming a wear-resistant, sintered layer on an iron based substrate which comprises steps of providing a first alloy sheet containing 94 to 99 weight % of Fe-Cr type alloy particles and 6 to 1 weight % of acryl binder and a second alloy sheet containing 94 to 99 weight % of eutectic alloy particles and 6 to 1 weight % of acryl binder, placing the first and second alloy sheets in a superposed condition on the substrate, and heating in a non-oxidating atmosphere to a temperature which is higher than a solidus temperature of the eutectic alloy but lower than a solidus temperature of the Fe-Cr type alloy.

Abstract: A process for making a strip or sheet comprising dispersion strengthened metal or dispersion strengthened metal alloy which comprises rolling directly from dispersion strengthened metal powder to a green strip or sheet density of from at least 90% to 95% of theoretical density, sintering the green strip or sheet in an inert atmosphere at a temperature and for a period of time sufficient to form a rigid body; reducing the thickness of the strip or sheet by at least 25% by cold rolling or hot rolling and resintering at sintering temperature of at least about 1800.degree. F. for 40 to 75 or more minutes.

Abstract: A method of manufacturing a scandate dispenser cathode having a matrix at least the top layer of which at the surface consists substantially of tungsten (W) and scandium oxide (Sc.sub.2 O.sub.3) and with emitter material in or below said matrix. If said method comprises the following steps:(a) compressing a porous plug of tungsten powder(b) heating said plug in a non-reactive atmosphere and in contact with scandium to above the melting temperature of scandium,(c) cooling the plug in a hydrogen (H.sub.2) atmosphere(d) pulverizing the plug to fragments(e) heating said fragments to approximately 800.degree. C. and firing them at this temperature for a few to a few tens of minutes in a hydrogen atmosphere and slowly cooling in said hydrogen atmosphere(f) grinding the fragments to scandium hydride-tungsten powder (ScH.sub.2 /W)(g) compressing a matrix or a top layer on a matrix of pure tungsten from said ScH.sub.

Abstract: The present invention discloses a method for densifying previously sintered parts constructed of powdered metals, ceramics or the like to nearly 100% theoretical density. The method of the present invention comprises heating the parts containing binder and hard phase above their liquid phase temperature and then applying a pressure in a predetermined range to the parts for a predetermined period of time and simultaneously maintaining the parts at or above their liquid phase temperature. This pressure range is set so that the pressure is below the pressure necessary to overcome the capillary force acting on the binder to keep the binder from entering the voids but above the pressure necessary to physically move or collapse the microstructure inwardly, thus filling the voids with a homogenous mixture of binder and hard phase. The method of the present invention achieves complete closure of even large voids and the elimination of substantially all porosity within the part.

Abstract: A method for sealing porous metals, which comprises applying powder of a eutectic alloy containing an element having a good diffusibility in a porous metal or powder of a mixture of metals capable of forming the eutectic alloy, to the surface of a porous metal member and heating the surface applied with the powder at a temperature higher than the eutectic temperature of the eutectic alloy to thereby cause the molten eutectic alloy to intrude into pores from the surface of the porous metal member, whereby the melting point of the molten alloy in the pores is promptly increased by diffusion of the element in the porous metal member to solidify the molten metal in the pores, sealing only pores present in the vicinity of the surface of the porous metal member.

Abstract: To increase the creep strength of a titanium-containing alloy which also contains chromium, the alloy powder is heated in the presence of ammonia at a temperature of the order of 700.degree. C. so as to form a layer of chromium nitride(s) on the particles and is then heated further in an inert atmosphere at a temperature between 1000.degree. C. and 1150.degree. C. to dissociate the chromium nitride(s) thereby effecting nitriding of the titanium to titanium nitride which affords dispersion-strengthening of the alloy.

Abstract: A hot isostatic pressing system including a hot isostatic pressing station having a high pressure container constituted by a vertical pressure-resistant cylinder closed at the top end thereof and a lower lid detachably fitted to the bottom of the pressure resistant cylinder and a treating chamber internally provided with a heater and enclosed by a heat insulating wall, and a mechanism for adjusting an atmospheric gas pressure and temperature of the pressing station into a condition suitable for the hot isostatic pressing of a work item accommodated in the treating chamber; a plurality of auxiliary stations each provided with an opening for receiving from beneath thereof the heat insulating wall of the treating chamber accommodating the internal heater and a work item, a support structure for supporting the heat insulating wall, and a mechanism for cooling the work item and internal heater in an inert gas atmosphere; a carriage for transferring the lower lid and work item or the lower lid, work item, heat insu

Abstract: A composite material for a sliding member has a back metal layer and a graphite-containing phosphor bronze sintered layer bonded to the back metal layer. The graphite-containing phosphor bronze sintered layer consists essentially of 0.03 to 1 wt % phosphorus, 7.5 to 16 wt % tin, 1 to 8 wt % graphite and the balance copper, and is constituted by phosphor bronze powder passing through a 200-mesh screen and a graphite powder passing through a 350-mesh screen. Also disclosed is a method of manufacturing the above-mentioned composite material for a sliding member.

Abstract: The present invention discloses a method for densifying previously sintered parts constructed of powdered metals, ceramics or the like to nearly 100% theoretical density. The method of the present invention comprises heating the parts containing binder and hard phase above their liquid phase temperature and then applying a pressure in a predetermined range to the parts for a predetermined period of time and simultaneously maintaining the parts at or above their liquid phase temperature. This pressure range is set so that the pressure is below the pressure necessary to overcome the capillary force acting on the binder to keep the binder from entering the voids but above the pressure necessary to physically move or collapse themicrostructure inwardly, thus filling the voids with a homogeneous mixture of binder and hard phase. The method of the present invention achieves complete closure of even large voids and the elimination of substantially all porosity within the part.

Abstract: A powder metallurgical method of producing metal bodies using spherical powder, produced by inert gas atomization, from magnetizable material with a particle size distribution closely approximating the so called Fuller curve for maximum density packing of spherical particles. Said powder is magnetized and filled into a form, which may take place before or after magnetization, said mixed and magnetized powder then sintered in said form with the exclusion of air, to produce a sintered body without communicating porosity.

Abstract: An object is manufactured from a powdered material by isostatic pressing of a body, preformed from the powdered material, with a pressure medium, whereby the preformed body, in which at least the surface layer consists of a ceramic material in the form of a nitride, is surrounded by a casing which is rendered impenetrable to the pressure medium, before the isostatic pressing is carried out and the powder sintered. As the material in the casing there is used boron oxide or a glass containing boron oxide or a material forming glass while being heated, in which the content of boron oxide is sufficiently high for the glass--or the glass formed during heating--to be removable by water. The preformed body surrounded by the casing is subjected to a heat treatment for the formation of boron nitride on the surface of the preformed body, before the isostatic pressing is carried out. The casing is removed from the finished product by means of water or water vapor.

Abstract: A sintered ferrous alloy which is high in wear resistance and relatively weak in the tendency to abrade another metal material with which the sintered alloy makes rubbing contact and suitable for rocker arm tips in automotive engines for example. The sintered alloy is produced by compacting and sintering a powder mixture of 15-50 parts by weight of a Fe-Cr-B alloy powder, which contains 10-35% of Cr and 1.0-2.5% of B, 1.0-3.5 parts by weight of graphite powder, such an amount of a Cu-P alloy powder that the powder mixture contains 0.2-1.5% of P and 1.0-20.0% of Cu and the balance of an iron powder.

Abstract: The present invention relates to a method for manufacturing a high-strength sintered silicon carbide article and more particularly, to a method for a sintered silicon carbide article having high mechanical strength by mixing a finely divided silicon carbide powder with the definite amounts of a specific carbon-containing material, a boron compound and silicon powder as densification aids, shaping and then sintering said shaped article under an inert atmosphere.

Abstract: A sintered ferrous alloy which is high in wear resistance and relatively weak in the tendency to abrade another metal material with which the sintered alloy makes rubbing contact. The sintered alloy is produced by compacting and sintering 100 parts by weight of a powder mixture of 5-35 parts by weight of a Fe-Cr-B-Si alloy powder, which contains 10-35% of Cr, 1.0-2.5% of B and 0.5-3.0% of Si, such an amount of a Cu-P alloy powder that the powder mixture contains 0.2-1.5% of P and 1.0 to 20.0% of Cu, and the balance of a cast iron powder. Preferably the cast iron powder contains 2.5-3.5% of C, 1.8-2.2% of Si and 0.6-1.0% of Mn. For example, the sintered alloy is suitable for rocker arm tips in automotive engines.

Abstract: Cobalt cemented carbide cutting inserts are prepared for coating with a hard, wear-resistant coating by providing a cobalt enriched zone on a surface to be coated. Cobalt enrichment is effectuated by means of nitrogen gas contact with the carbide followed by a period of vacuum sintering during its sintering process of manufacture.

Abstract: The solid cathodes built into reduction cells for aluminum production have at least one workface which can be wet by the precipitated metal. The starting materials, which contain titanium, boron and carbon in powder form, are first intimately mixed in such proportions that the sum of the powdered carbon and any carbon extracted from the substrate is in excess with respect to the amount required by the starting materials to form titanium diboride. This mixture is heated under a neutral or reducing atmosphere to 1600.degree.-2200.degree. C. and held for 5-45 min at this temperature. The reaction product containing pores and channels is then heated further, to 2250.degree.-2600.degree. C., and held there for 10-60 min to form a compact titanium diboride/carbon eutectic. Subsequently, the solid cathode is cooled to room temperature.

Abstract: Process for the preparation of a composite material incorporating an inorganic matrix in which are distributed inclusions of carbon-containing material, where it comprises the following stages:(a) mixing an inorganic powder with a liquid or viscous resin, which can be transformed into vitreous carbon by heat treatment,(b) subjecting the mixture of resin and inorganic powder to a first heat treatment performed under conditions such that the resin is hardened by crosslinking or polycondensation, and(c) subjecting the thus obtained hardened product to a second heat treatment for transforming the resin into vitreous carbon and thus forming said vitreous carbon inclusions.The composite material obtained comprises a copper matrix in which are uniformly and homogeneously dispersed vitreous carbon inclusions, the vitreous carbon content being at the most 8% by weight.The material is used in the production of electric contacts.

Abstract: The invention is refractory, electrically conductive, mixed materials based on hexagonal boron nitride and at least one electrically conductive component such as titanium boride and zirconium boride, and having a density of at least about 95% of the theoretical density and nondirection-dependent properties, which have been manufactured from powder mixtures that are practically free of oxygen and metal and comprisefrom about 10 to 60% by weight of boron nitride,from about 0 to 60% by weight of aluminum nitride and/or silicon nitride, andfrom about 30 to 70% by weight of an electrically conductive component,without the concomitant use of sintering aids by means of isostatic hot pressing in a vacuum-tight casing at temperatures of from about 1400.degree. to 1700.degree. C. and under a pressure of from about 100 to 300 MPa. The powder mixtures are pre-densified to form green bodies in block form and are then introduced into casings or coated with a material forming a vacuum-tight casing.

Abstract: This invention provides a process for producing a high quality powdered alloy such as cemented carbides, cermets, ceramics and iron-containing sintered alloys by sintering, characterized in that the sintering is carried out in a plasma gas atmosphere of H.sub.2, N.sub.2, CO, He and/or Ar.

Abstract: An inert electrode connection is disclosed wherein a layer of inert electrode material is bonded to a layer of conductive material by providing at least one intermediate layer of material therebetween comprising a predetermined ratio of inert material to conductive material. In a preferred embodiment, the connection is formed by placing in a die a layer of powdered inert material, at least one layer of a mixture of powdered inert material and conductive material, and a layer of powdered conductive material. The connection is then formed by pressing the material at 15,000-20,000 psi to form a powder compact and then densifying the powder compact in an inert or reducing atmosphere at a temperature of 1200.degree.-1500.degree. C.

Abstract: Workpieces pressed from metallic particles, impregnated with an organic lubricant, are sintered in a muffle furnace after traversing a preheating chamber serving for the removal of the lubricant. A substantially oxygen-free protective gas, consisting at least in part of combustible constituents, is passed in counterflow to the workpieces through the preheating chamber in which it is mixed with a hot oxygen-rich gas, preferably air, admitted into the chamber at locations spaced apart in the transport direction of the workpieces to burn the combustible components of the protective gas along with the evaporating lubricant; the oxygen content decreases progressively from a relatively high value near the entrance end of the preheating chamber, where the workpieces are protected from oxidation by their low initial temperature, toward the exit end. The entering air may be brought to a high temperature by heat exchange with the hot gas mixture leaving the chamber at its entrance end.

Abstract: The solid cathodes built into reduction cells for aluminum production have at least one workface which can be wet by the precipitated metal. The starting materials, which contain titanium, boron and carbon in powder form, are first intimately mixed in such proportions that the sum of the powdered carbon and any carbon extracted from the substrate is in excess with respect to the amount required by the starting materials to form titanium diboride. This mixture is heated under a neutral or reducing atmosphere to 1600.degree.-2200.degree. C. and held for 5-45 min at this temperature. The reaction product containing pores and channels is then heated further, to 2250.degree.-2600.degree. C., and held there for 10-60 min to form a compact titanium diboride/carbon eutectic. Subsequently, the solid cathode is cooled to room temperature.

Abstract: A wear-resistant hard metal free of tungsten carbide. The hard metal comprises: molybdenum carbide; a carbide of another transition metal; boron, boron nitride, boron carbide, or a mixture thereof, in an amount of 0.1 to 1% by weight boron, based on the weight of the molybdenum carbide, other transition metal carbide and boron-containing material, and a binder metal selected from the group consisting of metals of the iron group of the Periodic Table of Elements, and alloys thereof.

Abstract: The present invention relates to a process for producing a sintered porous metal plate comprising metal particles directly and integrally bonded together due to sintering, the plate being of porous construction and having a density gradient in the direction of thickness, comprising charging metal particles into a refractory mold, pressing the particles, passing an electric current therethrough to heat the metal particles approximately up to their transformation point and then heating the metal particles to effect sintering.

Abstract: A process for high temperature sintering of ferrous powder metallurgy compacts having a substantially uniform carbon distribution which comprises:(a) heating the ferrous powder metallurgy compact in the heating zone of a sintering furnace to a temperature of about 2,300.degree. to 2,550.degree. F. (1,260.degree. to 1,399.degree. C.),(b) introducing to the heating zone an atmosphere comprising about 2 to less than 10 volume percent hydrogen, about 0.5 to 2.0 volume percent carbon monoxide, about 0.5 to 1.0 volume percent methane and the balance nitrogen, and(c) removing the sintered product from the furnace.

Abstract: The method of the invention relates to powder metallurgy and is intended to be used for making cutting tools, dies as well as vital structural members.The method comprises charging a powder into a capsule, sealing the capsule, heating and then extruding the capsule containing the powder. The sealed capsule is heated up to a temperature of 700.degree. to 1000.degree. C., whereupon the capsule is depressurized and heated up to a temperature of 1050.degree. to 1200.degree. C.

Abstract: A foraminous body formed of a tin-containing atomized, compacted and sintered austenitic stainless steel powder, and process including the steps of sintering and cooling in a dissociated ammonia atmosphere.

Abstract: Copper base spinodal alloy strip of good strength and ductility is provided, the alloy containing 5 to 35 percent nickel, 7 to 13 percent tin, balance essentially copper, and having an unaged microstructure characterized by an equiaxed grain structure of substantially all alpha, face-centered-cubic phase with a substantially uniform dispersed concentration of tin and a substantial absence of tin segregation. The strip is prepared from copper alloy powder of the indicated composition by a process comprising the steps of compaction, sintering, cooling, rolling and annealing. The strip after aging may contain up to about 50 percent alpha plus gamma phase.

Abstract: This invention relates to a process for manufacturing R.sub.2 Co.sub.17 system permanent magnet alloys of rare earth(R)-cobalt(Co) intermetallic compounds. Sm.sub.2 Co.sub.17 alloy, in which R is samarium (Sm) with respect to intermetallic compounds whose stoichiometric composition is R.sub.2 Co.sub.17, possesses high saturation magnetization and high Curie temperature making it possible to obtain a high energy product. However, its permanent magnetization has not been practiced much at all because coercive force could not be obtained. This invention practices heat aging for 0.5-200 hours at 700.degree.-800.degree. C. in the heat treatment process of the sintered material of R.sub.2 (Co,Fe,M).sub.17 system (M is one or more than one elements of Ti, Cr, Mn, Ni, Cu, Zr, Nb, Hf, Ta, and W) and the coercive force is increased by carrying out this process in a magnetic field to achieve permanent magnetization.

Abstract: Hot briquetting apparatus for ferrous or non-ferrous particles has a furnace having upper and lower chambers. The particles are supplied to the lower chamber and leave the lower chamber through a discharge tube to enter a briquetting press. A passage is performed between the lower and upper chambers and sensing means sense the constituents of the gases in that passage. Control means control the air-to-fuel ratio of a zone of the lower chamber. The control means are connected to the output of the sensing means so as to maintain the atmosphere within the zone as a reducing atmosphere, the whole of the lower chamber being a reducing atmosphere.