Abstract: Sinter alloys based on high-speed steel are proposed, which can be used for producing wearing parts in machinery and vehicle contruction. The sinter alloys comprise a mixture of a powder of a high-speed steel and an unalloyed or a low-alloy iron powder. While the high-speed steel powder forms liquid phases upon sintering, the mixture components can be drawn from either the group of iron alloys that do not form liquid phases or the group of iron alloys that do form liquid phases. The proposed alloys cannot be sintered to the density of the high-speed steels, nor do they quite attain the strength values of such steels, but in the cases where these limit values for strength are not critical they have the decisive advantage that they can be sintered without deformation in standard protective gas furnaces lacking extreme temperature constancy and that they furthermore exhibit only very slight shrinkage.

Abstract: The invention concerns alloys comprising a matrix based on at least one conductor metal M, formed by a homogeneous dispersion in the matrix of stable coherent particles of one or more associations of ions of type M, M', O in which M represents the metal or metals of the matrix, M' represents a different metal from M, which is capable of undergoing internal oxidation, and O represents oxygen.It also concerns the process for the production of such alloys which comprises subjecting a starting alloy powder to the action of an oxidizing agent formed by a powder with a granulometry of the order of 1 .mu.m of a metal oxide capable by thermal decomposition of providing the oxygen necessary for the internal oxidization of M', the starting alloy being based on at least one metal M, if appropriate hardened by one or more elements R or A as defined hereinbefore.Use of such alloys for the electrical, electronic and connection arts.

Abstract: A process is disclosed for producing tungsten heavy alloy billets. The process involves forming a uniform blend of elemental powders to form a tungsten alloy having a tungsten content of equal to or less than about 91% by weight and wherein the particle size of the tungsten is no less than about 2 micrometers in diameter. This blend is uniformly packed into a container having thermal expansion similar to that of the powder. The blend is then sintered in a hydrogen atmosphere at a temperature sufficient to impart strength to the powder and to reduce oxides and remove volatile impurities from the powder without significant densification in the powder. The powder is then solid state sintered in a reducing atmosphere at a sufficient temperature to densify the powder to at least about 90% of the theoretical density but at a temperature below the liquid phase sintering temperature of the powder, to form the billet.

Abstract: A method of producing ferrous sintered alloys comprises the steps of preparing mixed alloy powder containing Fe-P-C eutectic alloy powder which includes phosphorus within the range of 2.0% to 3.0% by weight, carbon not more than 4.0% by weight and one of molybdenum within the range of 8.0% to 11.0% by weight and boron within the range of 0.5% to 3.0% by weight, graphite, and ferroalloy powder containing chromium within the range of 11% to 14% by weight; causing the mixed alloy powder to be subjected to compression molding to have a green compact; and sintering the green compact to have a ferrous sintered alloy containing compound carbides in a matrix structure thereof. The graphite is so selected that the sum total of the graphite and the carbon included in the Fe-P-C eutectic alloy powder constitutes a part within the range of 5% to 8% by weight of the sum total of the graphite and the Fe-P-C eutectic alloy powder.

Abstract: This invention provides a shaped, graded, cermet article comprising at least one continuous ceramic phase and at least one discontinuous metal phase, the ratio of ceramic/metal being controlled and varied over the thickness of the article. The ceramic phase preferably is microcrystalline.

Abstract: A copper or copper alloy infiltrated ferrous powder metal part, and method for making the same, characterized as having after infiltration an overall density of at least 7.50 g/cm.sup.3 and a diffusion depth of copper into the steel matrix of less than about 4 micrometers as determined by chemical etching or less than about 8 micrometers as determined by electron dispersive X-ray analysis (EDXA), wherein said ferrous metal is plain carbon steel having a combined carbon content in the range of about 0.15% to about 1.25%, or a low alloy steel.

Abstract: A method for utilizing a powder metallurgy ("P/M") slurry by employing water atomized metallic powders and subsequently reducing the oxide levels therein to acceptable levels. The slurry comprises a carbon containing binder. The slurry is consolidated and sintered under controlled conditions to reduce the oxide levels.

Abstract: A process is disclosed for producing composite agglomerates of molybdenum and molybdenum carbide (Mo.sub.2 C). The process involves forming a relatively uniform mixture of non-agglomerated molybdenum powder and carbon powder having a particle size of no greater than the particle size of the molybdenum powder. The amount of carbon powder is proportional to the amount of molybdenum carbide desired in the composite agglomerate. A slurry is formed of the mixture, an organic binder, and water with the amount of the binder being no greater than about 2% by weight of the mixture; and the powders are agglomerated from the slurry. The agglomerated powders are then classified to remove the major portion of the agglomerates having a size greater than about 170 mesh and less than about 325 mesh from the balance of the agglomerates. The balance of the agglomerates in which the particle size is -170 +325 mesh is then reacted at a temperature of no greater than about 1400.degree. C.

Abstract: The powdered material contains oxygen in the oxide and/or adsorbed form and the oxygen present is reduced in a first pre-sintering stage and the cohesion of the material is ensured in a second sintering stage. The pre-sintering stage is carried out under a reducing atmosphere based on hydrogen and neutral gas whose flow rate F.sub.G is higher than or equal to: ##EQU1## in which relation: S.sub.P =section of the layer of powder to be sintered in sq.mD.sub.P =voluminal mass of the powder in kg/cu mX(O.sub.2)i=percentage of oxygen mass in the powder before the pre-sintering stage, in the oxide and/or adsorbed form,P(H.sub.2)i=voluminal percentage of hydrogen in the gas introduced into the furnace,P(H.sub.2)f=the smallest voluminal percentage of hydrogen in the atmosphere in the furnace at a point where the oxides have been completely reduced,v.sub.S =speed of feed of the material in the furnace expressed in m/hr,.alpha. is a constantF.sub.G being expressed in cu.m/hr.

Abstract: This invention relates to a sintering process. More particularly, this invention relates to a process for preparing a sintered form having a tungsten content which comprises the steps of:(a) sintering a porous form of pressed tungsten alloy powders having a high tungsten content in solid phase, and(b) heat treating the sintered part from step (a) in a liquid phase.

Abstract: A sintered tungsten carbide material and method for manufacturing same in which the method includes the steps of combining metal particles composed of from 75 to 95 percent by weight of a composition containing at least 70 percent by weight of tungsten carbide and from 5 to 25 percent by weight of a binder metal composition, the binder metal composition consisting essentially of from 5 to 15 percent by weight of chromium and from 85 to 95 percent by weight of nickel; pressing the metal particles into a pressed body; sintering the pressed body in a sintering chamber for a period ranging from 20 to 200 minutes, at a temperature ranging from 1400.degree. to 1500.degree. C., and in a protective atmosphere which is one of a vacuum, a noble gas, a mixture of noble gases, and hydrogen gas to form a sintered body; and treating the sintered body for a period ranging from 20 to 200 minutes, at a temperature ranging from 1300.degree. to 1400.degree. C.

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 method of producing a sliding composite material. The method comprises the step of: forming an adhesive layer bonded to the surface of a metal strip by sintering a powder for the adhesive layer which contains no solid lubricant and which is disposed onto the surface of the metal strip; forming a surface layer by sintering another powder for the surface layer which contains a solid lubricant and which is disposed onto the sintered adhesive layer; and rolling the resulting layers and the metal strip to obtain the composite material.

Abstract: A wear resistant iron alloy article is preferably formed by compacting and sintering a predominantly iron powder mixture containing additions of carbon, copper and nickel boride. The product microstructure comprises hard borocementite particles dispersed in a martensite or pearlite matrix. The particles have a cross-sectional dimension greater than 1 micron and are present in an amount preferably between 10 and 30 volume percent to improve wear resistance.

Abstract: A tetrafluoroethylene-type fluoroplastic powder is added and mixed with a metal powder and the mixture is shaped. The compact is heated in a nonoxidizing atmosphere and the oxides on the surface of the metal particles are converted and removed as gaseous fluorides. Alternatively, after the oxides are converted to solid or liquid fluorides, the fluorides are reduced by hydrogen and then they are removed as gaseous reaction products. Thereafter, the compact is sintered.

Abstract: There is disclosed a process for forming a wear-resistant, sintered layer on a metallic substrate. The process comprises steps of adhesively attaching to a surface of metallic substrate an alloy particle sheet containing 94 to 99 weight % of ternary eutectic alloy particles and 6 to 1 weight % of acryl binder, heating in a non-oxidating atmosphere to a temperature of 150.degree. to 380.degree. C. and holding at the temperature for at least 5 minutes, and heating a sintering temperature of the alloy particles.

Abstract: A three step process in which a metal alloy selected from a tungsten based alloy and molybdenum based alloys is provided to prevent the decarbonization of the alloys. The process involves a three step sintering process wherein the atmosphere during the initial heating step is a mixture of carbon monoxide and hydrogen, thereafter at a intermediate temperature range the atmosphere is hydrogen and a final heating step at a elevated temperature is employed and the atmosphere is a mixture of inert gas and a source of carbon.

Abstract: The disclosure relates to a method of rapidly removing binder from a "green" body composed of metal or cermet fine particles and a carbon-containing binder wherein the debinderizing step is performed in a water saturated atmosphere to provide chemical reaction with elemental carbon, the reaction products being removed from the system.

Abstract: A nickel anode electrode fabricated by oxidizing a nickel alloying material to produce a material whose exterior contains nickel oxide and whose interior contains nickel metal throughout which is dispersed the oxide of the alloying material and by reducing and sintering the oxidized material to form a product having a nickel metal exterior and an interior containing nickel metal throughout which is dispersed the oxide of the alloying material.

Abstract: A method for fabricating ribbed electrodes that accommodates the shrinkage which occurs during thermal cycling reducing the cracks caused by the confining stresses of a mold. A composition comprising a metal selected from the group consisting of nickel, copper and mixtures thereof with chromium onto a ribbed mold. The mold and composition are prefired in a reducing atmosphere forming a ribbed electrode. The ribbed electrode is removed from the mold and sintered in a reducing atmosphere.

Abstract: A method is disclosed for making a fuel pellet for a nuclear reactor. A mixture is prepared of PuO.sub.2 and UO.sub.2 powders, where the mixture contains at least about 30% PuO.sub.2, and where at least about 12% of the Pu is the Pu.sup.240 isotope. To this mixture is added about 0.3 to about 5% of a binder having a melting point of at least about 250.degree. F. The mixture is pressed to form a slug and the slug is granulated. Up to about 4.7% of a lubricant having a melting point of at least about 330.degree. F. is added to the granulated slug. Both the binder and the lubricant are selected from a group consisting of polyvinyl carboxylate, polyvinyl alcohol, naturally occurring high molecular weight cellulosic polymers, chemically modified high molecular weight cellulosic polymers, and mixtures thereof. The mixture is pressed to form a pellet and the pellet is sintered.

Abstract: An electrical contact formed of a mixture of finely divided electrically conductive metal doped with graphite or cadmium oxide. A thin coating of the electrically conductive metal is disposed upon the side of the contact which is adapted to be welded or brazed to an electrically conductive support. The electrical contact is made by mixing the finely divided cadmium oxide and pressing the mixture into a desired shape. A slurry of conductive metal is then sprayed on one side of the contact. After coating, the contact is sintered at a temperature less than the melting point of the electrically conductive material, whereby the contact is formed and the coating is firmly attached to it. The invention is particularly useful with silver or copper-based electrical contacts.

Abstract: The present invention provides a molybdenum alloy which suitably comprises in the range of from 0.2 to 1.0% by weight of an oxide of a specified metal prepared by adding a salt of the metal in dissolved form to molybdenum and/or a molybdenum oxide or a mixture of different molybdenum components, reducing this mixture at a temperature of up to 1150.degree. C. using hydrogen, pressing the reduced metal without the addition of a binder suitably under a pressure of from 150 to 300 mPA, and sintering the product at a temperature in the range of from 1750.degree. to 2200.degree. C. It is preferable to add salts of zirconium to the molybdenum oxide.

Abstract: The invention relates to a process for the treatment of a metal oxide powder, particularly a UO.sub.2 or PuO.sub.2 powder, with a view to its fritting.This process consists of oxidizing the powder, so as to form on its surface a hydrated oxide layer of the same metal. When the oxide is UO.sub.2 or PuO.sub.2 and mixtures thereof, as well as those prepared with ThO.sub.2, the treated powder can be used for producing nuclear fuel pellets by cold compression, followed by fritting.

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: A high strength powder metal part formed from an alloy of iron, nickel, molybdenum and carbon and having an ultimate tensile strength of at least 175,000 pounds per square inch. The powder metal part is made by mixing the alloy with a lubricant, forming the mixture into the desired part shape, sintering in a dissociated ammonia atmosphere, and cryogenically cooling the sintered part.

Abstract: Powder metal compositions of nickel, molybdenum, boron, carbon, phosphorus and iron which exhibit low shrinkage on sintering.

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: An improvement is disclosed in a process for recovery of cobalt from cobalt bearing material to obtain fine cobalt metal powder of high purity, the improvement being mechanically compacting the powder into a billet and sintering the billet in a hydrogen atmosphere at a sufficient temperature for a sufficient time to densify the billet and form a high purity cobalt article having an oxygen content of no greater than about 500 weight parts per million.

Abstract: A method of producing a high density tungsten alloy sheet product is disclosed which utilizes as a starting material a thin-gage sheet or foil substrate of a first alloy constituent, such as pure iron or an alloy thereof. A prescribed mixture of tungsten metal powder and a second metal alloy constitutent powder, such as nickel, is loaded on the substrate and partially consolidated in a protective atmosphere furnace to form a porous tungsten alloy skeleton which is also partially bonded to the substrate. The product is then preferably cooled in a protective atmosphere and sheared into desired lengths. The sized pieces are then further heated in a protective atmosphere at gradually increasing temperatures to a point above the melting point of the substrate, whereupon the substrate sheet or foil melts and infiltrates the porous tungsten alloy skeleton to complete the densification of the product.

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: 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: 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: In a process for sintering a metal member bonded to a substrate during which the metal member undergoes densification at a temperature which is different from the curing temperature of the substrate, an improvement is provided which comprises causing the densification temperature of the metal member to be closer to or identical with the curing temperature of the substrate by adding to said metal member prior to sintering an amount of organometallic compound which undergoes decomposition before the densification temperature of the metal member has been reached to provide under the sintering conditions employed a densification temperature-modifying amount of a metal or metal oxide which can be the same as or different from the metal of the aforesaid metal member.The improved sintering process of the present invention is particularly adapted for use in the fabrication of multilayer ceramic substrates which serve as circuit modules for seminconductor chips.

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 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: 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: A canless method for hot working a nickel-base gas atomized alloy powder. The powder is blended with nickel powder, consolidated and sintered to a sufficient green strength. The surface of the resultant form is sealed to create an oxygen impervious layer so as to prevent oxidation therein. The sealed surface, in a sense, acts as a can. The form is then reheated and hot worked.

Abstract: A method of producing rocket combustors wherein in forming an outer cylin by a powder metallurgical method on the outer side of a cylinder provided on its outer periphery with a cooling wall of channel construction having a plurality of grooves, a low-melting alloy is used as a filler to be filled into the grooves. It is also possible to form the outer cylinder after forming a Cu plating shell on the periphery of the inner cylinder filled with the low-melting alloy.

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: The present invention provides a method for controlling the carbon content of dewaxed carbide preforms in a carbon containing furnace. The method includes the steps of placing the preforms in a carbon containing furnace and then heating the furnace to a predetermined temperature range between 800 and 1100 degrees Centigrade. At that temperature, a mixture of methane and hydrogen is introduced into the furnace chamber such that the amount of methane is between 10 and 90 percent of the amount of methane present at equilibrium for the reaction C.sub.solid +2H.sub.2 .revreaction.CH.sub.4. The furnace chamber is maintained at its temperature for a first time period sufficient for the chemical reaction XC+2H2.revreaction.X+CH.sub.4 (where X is selected from the group of W, Ti, Ta, Hf and No) substantially reaches equilibrium but shorter than the a second time period in which the reaction C.sub.solid +2H2.revreaction.CH.sub.

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: 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 disclosed electrode composition for a vacuum switch comprises copper, as a principal ingredient, a low melting point metal such as Bi, Pb, In, Li, Sn or any of their alloys, in a content not exceeding 20% by weight, a first additional metal such as Te, Sb, La, Mg or any of their alloys and a refractory metal such as Cr, Fe, Co, Ni, Ti, W or any of their alloys in a content less than 40% by weight.

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: A method of manufacturing molded articles of metal alloys, especially of nickel-base alloys, chromium-base alloys, titanium-base alloys, and dispersion-hardened alloys. A powder of the alloy, or a blend of powders of alloy constituents, is mixed with one or more plastics, selected from thermoplastics, duroplastics, and internal lubricants to form an injectionable granulate compound, the plastic content amounting to about 30% to 50% by volume. The compound is prepared by dissolving the plastic in a solvent which will not attack the base material of the alloy, and by blending it with the metal powder, after which the solvent is evaporated. The injectionable granulate compound is then injection molded to form a molded article. By heat treatment at 600.degree. C. or below in inert gas the plastic is eliminated from the molded article. The article is then sintered. To improve its strength, the article may subsequently be subjected to hot isostatic pressing.

Abstract: A method of producing a rotary dresser include forming a core piece of an iron-base powder and filling in tungsten or like metal powder between the core and an outer mold member containing diamond grit or the like. The construction is then heated to melt and infiltrate a metal alloy, such that a network structure is formed about the powdered metal particles. In a further embodiment, the metal materials may be arranged in concentric form about a metal bushing such that the bushing is included in the final structure.

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: Porous bodies are produced by sintering a body of nickel powder incorporating from 0.35 to 2.0% by weight of carbon under a reducing gas at a temperature above 750.degree. C. but below 1050.degree. C. At least part of the carbon may be mixed with the powder as finely divided graphite.

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.