Abstract: A process for fabrication of sintered metal components having improved mechanical, physical and wear-resistent properties.

Abstract: A process for producing titanium aluminide weld rod comprising: attaching one end of a metal tube to a vacuum line; placing a means between said vacuum line and a junction of the metal tube to prevent powder from entering the vacuum line; inducing a vacuum within the tube; placing a mixture of titanium and aluminum powder in the tube and employing means to impact the powder in the tube to a filled tube; heating the tube in the vacuum at a temperature sufficient to initiate a high-temperature synthesis (SHS) reaction between the titanium and aluminum; and lowering the temperature to ambient temperature to obtain a intermetallic titanium aluminide alloy weld rod.

Abstract: A cermet useful in the fabrication of metal cutting, rockdrilling and mineral tools, as well as wear parts. The cermet comprises (i) a hard phase of a simple boride of a transition metal, a mixture of simple borides of transition metals, or a mixed boride of transition metals; (ii) a binder phase of Fe, Ni, Co, Cr, or alloys thereof; (iii) a dispersion of particles of oxides of transition metals in which the oxygen can be replaced by nitrogen and/or carbon; and (iv) a dispersion of oxides of metals chosen from aluminum and Group IIA and IIIA metals.

Abstract: A magneto-optical sputter target having a composition comprising at least one rare earth element and at least one transition metal, with a structure which includes a transition metal constituent and a finely mixed alloy constituent of a rare earth phase and a rare earth/transition metal intermetallic compound. The structure of the present target contains a minimum of the intermetallic compound. A method of producing the present sputter target includes mixing particles of the transition metal constituent (preferably only alloyed transition metals) with particles of the finely mixed alloy to produce a powder blend and subjecting the powder blend to a pressing operation in an oxidizing inhibiting environment for a time and at a temperature and pressure which minimizes the rare earth/transition metal intermetallic compound content of the target.

Abstract: Brazed structures are disassembled with little or no physical damage to the components by coating the brazed joints with a powdered wicking agent, preferably mixed with a fugitive liquid binder to form an adherent slurry, then heating the joint to allow the brazing alloy to melt and be drawn into the powdered wicking agent by capillary action. After cooling, the powder and braze alloy are mixed together to form a loosely consolidated mass which can be readily removed by mechanical and/or chemical means so that the components can then be separated for repair or reuse.

Abstract: A porous living body repairing member obtained by compression-molding a metal fiber material into a desired shape, sintering the fiber mesh body or thereafter, and imparting a compressive stress of not more than 4.00 to 40.0 MPa to provide a porous living body repairing member having a compressive elasticity of not more than 2000 MPa and a permanent deformation of not more than 1% under a stress below a compressive yield stress.The compressive yield stress becomes approximately equal to the above compressive stress, and almost complete elasticity of a permanent deformation rate of not more than 0.1% is shown with respect to a compressive stress below this compressive yield stress. Accordingly, even when the porous living body repairing member is used at a high compressive load site such as man's lumbar body, permanent deformation hardly occurs.

Abstract: A fiber reinforced composite tape is made by casting a mixture comprising high temperature metal or intermetallic particles, substantially continuous ceramic fibers and a polymeric binder. The particles are preferably titanium alloy or titanium aluminide particles having a top size of greater than about 50 microns and the binder is preferably a polyisobutylene. The cast composite tape is combined with other tapes, heated in a vacuum to remove the binder and pressed at an elevated temperature and pressure to form a composite structure suitable for high temperature applications.

Abstract: Disclosed is a stainless steel member with a high corrosion resistance suitable for a structural member used in highly corrosive environments, such as an edge seal plate of a molten carbonate fuel cell. This stainless steel member includes a base material consisting of stainless steel containing chromium, and a corrosion-protective layer formed on the surface of the base material. In this corrosion-protective layer, a granular heterophase containing chromium is precipitated in an ordered alloy consisting of aluminum and the constituent elements of the base material.

Abstract: The present invention provides an Al-Si based sintered alloy of high strength and high ductility, a method for production thereof and use thereof. The alloy comprises 1-45% of Si, 0.1-20% of an element of Group IIIa, 0.01-5% of at least one element of Groups IVa and Va, the balance of substantially Al. This alloy can further contain at least one of 0.01-5% of Cu, 0.01-5% of Mg, 2.0% or less of Fe, 1.5% or less of Mn and 1.5% or less of Co and the oxygen content is reduced to 0.15% or less by sintering under vacuum. The present invention is applied to automobile parts such as a piston and scroll compressors. The alloy has a tensile strength of about 40 kg/mm.sup.2 or higher and an elongation of 1.5% or more at 150.degree. C.

Abstract: The present invention relates to a process for making an aluminum silicon carbide composite material in strip form. The process comprises blending a powdered aluminum matrix material and a powdered silicon carbide material, roll compacting the blended powdered materials in an inert atmosphere to form a green strip having a first thickness, and directly hot working the blended and roll compacted materials to bond the aluminum matrix material particles and the silicon carbide particles and to form a thin strip material having a desired thickness.

Abstract: A composite soft magnetic material is produced from soft magnetic metal (e.g., Sendust) particles by coating the particles with a non-magnetic metal oxide (e.g., .alpha.-alumina) in a mechano-fusion manner, or heat treating the particles to form a diffusion layer of .alpha.-alumina thereon, coating the coated particles with a high resistance soft magnetic substance (e.g., ferrite), and sintering the double coated particles under pressure as by hot pressing or plasma activated sintering. It exhibits high saturation magnetic flux density, magnetic permeability, and electric resistivity. The non-magnetic metal oxide intervening between the soft magnetic metal and the high resistance soft magnetic substance is effective in reducing core loss.

Abstract: A process for making a non magnetic Ni-WC cemented carbide composition and articles made from the same. The process comprises:(a) dewaxing a green Ni-WC cemented carbide substrate in the presence of hydrogen gas at a pressure less than about 1000 torr and at a sufficient flow rate and a sufficient time to affect the saturation magnetization and magnetic permeability of the Ni-WC cemented carbide substrate;(b) pumping out the hydrogen gas and introducing argon at a pressure in the range of about 1 torr to 1000 torr;(c) increasing the temperature up to the sintering temperature to facilitate sintering of the Ni-WC cemented carbide substrate; and;(d) cooling the furnace to room temperature.The articles made according to this invention are useful as wear parts for electronic instruments and as punches form aluminum beverage cans.

Abstract: Methods of fabricating anodes for high temperature fuel cell in which an alloy powder with a major phase of a base metal and a minor phase of a stabilizing, alloying metal is preformed into the shape wanted in the anode. This green structure is sintered under conditions which produce a metallic, essentially oxygen-free structure. The sintered structure is selectively oxidized in situ in a fuel cell under conditions which promote internal oxidation and a consequent increase in the stability of the anode under operating conditions where the anode is exposed to high temperatures for long periods of time.

Abstract: The invention provides a composite soft magnetic material which is prepared by coating soft magnetic metal particles with a high resistance soft magnetic substance, preferably by mechano-fusion, applying electricity to the coated particles in a mold cavity between punches serving as electrodes, for example, to thereby create a plasma, and thereafter further conducting electricity to effect plasma activated sintering. There is obtained a composite material which possesses both the high saturation magnetic flux density and high magnetic permeability characteristic of the soft magnetic metal and the high electric resistivity characteristic of the high resistance soft magnetic substance.

Abstract: Methods and apparatus for protecting extruded metal powder green bodies (34) during firing are provided. In certain embodiments, one or more green bodies (34) are housed in a non-gas tight chamber (13) located in the hot zone (24) of a cold-wall vacuum/atmosphere furnace (10). Furnace gas, e.g., hydrogen, is supplied to the interior of the chamber (13). The resulting one-way flow out of the chamber (13) protects the green bodies (34) from the backflow of burn-out products, as well as from contaminants arising from the walls and internal components of the furnace (10). In other embodiments, green bodies (34) are housed in individual non-gas tight containers (36). The containers (36) minimize the amount of furnace gas which comes into contact with the green bodies (34) during sintering and thus minimize the level of exposure of the green bodies (34) to oxidative impurities in the furnace gas. When composed of the same material as the green bodies, the containers (36) also perform a getter function.

Abstract: It is provided a method for the manufacture of a corrosion-resistant sintered alloy steel, which comprises providing a stainless steel powder; adding a binder to said steel powder; molding the mixture; and carrying out the steps of (1) heating the resultant molding to remove the binder therefrom, (2) sintering the thus debound molding under reduced pressure up to 30 Torr, and (3) further sintering at a higher temperature than those of steps (1) and (2) in a non-oxidative atmosphere under substantially atmospheric pressure. It is also provided a corrosion-resistant sintered alloy steel which comprises a stainless steel, said alloy steel having a density ratio of not less than 92%, a maximum diametric of pore present in the structure of not larger than 20 .mu.m, and a content of Cr at the surface of the steel as being sintered which is not less than 80% of a content of Cr in the inside thereof.

Abstract: Disclosed is an electrically conductive sintered silicon carbide body having an electric resistivity of not higher than 1 .OMEGA..multidot.cm, which is produced by(a) mixing(1) a first silicon carbide powder having a mean grain size of from 0.1 to 10 .mu.m with(2) a second silicon carbide powder having a mean grain size of not greater than 0.1 .mu.m prepared by(2-1) introducing a starting gas composed of a silane compound of silicon halide and a hydrocarbon into a plasma of a non-oxidative atmosphere, and(2-2) conducting gas phase reaction between the silane compound or silicon halide and the hydrocarbon while controlling the pressure of the reaction system within the range of from less than 1 atom to 0.1 torr, and(3) optionally, a carbon powder which is required for reducing oxides contained in both the first and second silicon carbide powders,(b) optionally reducing the oxides with the carbon, and(c) heating the resulting mixture for sintering. Also, processes of producing the same are disclosed.

Abstract: A method for consolidating or densifying material selected from metal, ceramic or mixtures thereof to form a densified compact article, which process includes (a) arranging the sample to be consolidated or densified in a general configuration within a temperature controlled high pressure chamber completely surrounded by a pre-glass material which forms a glass at elevated temperature in close proximity and surrounded by a heating element within the pre-glass material and having at least one temperature measuring device in close proximity to the sample all located within a shell; (b) externally heating the arrangement produced in step (a) at an elevated temperature for a time effective to remove moisture, volatiles, impurities, volatile oxides or mixtures thereof; (c) heating the sample produced in step (c) to produce fusion of the pre-glass at between about 500.degree. to 1600.degree. C.

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

Abstract: A sintered body is produced by a process comprising the steps of mixing one or more metal powder particles with an organic binder, injection-molding the mixture to form a green body of a predetermined shape, removing the binder from the green body to form a porous body substantially made of the metal powder, and heating the porous body to a sintering temperature and holding it at that temperature to produce a sintered body, in which process the binder is removed through the sequence of the following steps: preheating the green body in an inert gas atmosphere in a temperature range that creates open pores in it; placing the green body, in which open pores have started to form, in a hydrogen gas atmosphere optionally mixed with an inert gas; holding the green body in a temperature range where the metal powder is not carburized and where the open pores will be maintained, so that the greater part of the binder is removed to form a porous body that is substantially made of the metal powder alone; and further hold

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

Abstract: A presinter treatment is provided to reduce oxygen contamination prior to sintering a predominantly iron powder compact comprising carbon powder and a liquating diffusible boron source, such as nickel boride powder optionally in combination with iron boride powder. A preferred treatment is carried out at a temperature effective to dissociate iron oxide within the compact but not to initiate a liquid phase by said boron source and further is carried out in a vacuum to evacuate oxygen released thereby from compact pores prior to sintering. The presinter treatment enhances carbon and boron diffusion into the iron during sintering. In a preferred embodiment, the fraction of borocementite particles formed by diffused carbon and boron in the sintered iron structure is increased by the presinter treatment of this invention.

Abstract: A tungsten heavy alloy system is modified by replacing from 2% to 10% of the tungsten by weight with tantalum to increase the strength and hardness characteristics for the alloy. This renders the alloy particularly useful for kinetic energy penetrators.

Abstract: A method of powder metallurgically manufacturing an article with near net shape is disclosed, the method comprisingfilling the mould cavity (3) of an open ceramic open mould (1), the inside walls of the cavity being precision copying cast surfaces (2), with fine particulate metal powder (5),placing the mould with its content of metal powder in an outer mould (6), and covering the ceramic open mould containing the metal powder with a bed of finely distributed particulate pressure medium (7),heating the bed of pressure medium and ceramic mould and particulate metal powder therein and subjecting the particulate pressure medium to pressure provided by at least one surface acting in an axial direction against the opening (4) of the ceramic mould, so that pressure is transferred by the particulate pressure medium to the metal powder in the mould to consolidate the metal powder to a completely dense body (21) with surfaces (22) which have been shaped by the precision cast surfaces of the mould cavity.

Abstract: A process for preparing dense, consolidated bodies, the process comprising compressing in a forging press an isostatic die assembly, the assembly comprising a preform surrounded by a fluid pressure-transmitting medium, the medium and the preform being contained in a shell having an open top; under sufficient conditions of temperature, time and pressure that a dense, consolidated body of desired shape is formed, and then recovering the body by separating the body from the fluid pressure-transmitting medium.

Abstract: A system to prevent, retard or reverse the decomposition of silicon carbide articles during high temperature plasma sintering. Preferably, the system comprises sintering a silicon carbide refractory or ceramic green body in a closed sintering environment, such as a closed tube, with strategic placement of the plasma torch or torches, exhaust outlet and tube. As sintering proceeds, a silicon vapor pressure builds up within the tube, retarding the decomposition of the silicon carbide body. The plasma torch, exhaust outlet, and tubes are positioned so that buoyant convective flow is maximized to increase the heat transfer and energy efficiency. In another embodiment, a "sacrificial" source of silicon carbide is placed into the sintering furnace. The silicon carbide in the sacrificial source starts to decompose before the silicon carbide refractory or ceramic article, creating a supersaturated atmosphere of silicon vapor species in the furnace.

Abstract: A method is disclosed for manufacturing a reaction sintered composite article which comprises at least one ceramic component. The method comprises preparing a particulate mixture of precursor powders leading to the formation of said composite material upon reaction sintering, pressing said particulate mixture to a self-sustaining body, heating said body up to a temperature below the temperature at which the reaction sintering is initiated, comminuting the heat treating body, selecting particles of a suitable grain size distribution, pressing said particles into shapes of desired size and configuration, and heating said shapes up to a temperature at which the reaction sintering is initiated. The reaction sintered body comprises borides, carbides, nitrides or silicides of a transition metal of the groups IVb, Vb or VIb of the periodic table (comprising titanium, hafnium, zirconium, vanadium, niobium, tantalum, chromium, molybdenum and tungsten), and a metal oxide.

Abstract: The invention resides in a process of preparing an inhomogeneous sintered body by adjoining metal powder with refractory ceramic powder at normal powder metallurgical pressures and sintering conditions. The invention is characterized thereby that the sintered body is manufactured in one layer or several layers having displaced mixing ratio between the ceramics and the metal and that the binding between ceramics and metal is strengthened with monoaluminium phosphate or a monoaluminium phosphate former. The sintered body can be used for example as heat shielding.

Abstract: A preformed body (12) from powder material of metallic and nonmetallic compositions and combinations thereof, is consolidated to form a densified compact (12") of a predetermined density. An outer container mass (20), capable of fluidity in response to predetermined forces and temperatures and which is porous to gases at lesser temperatures and forces than said predetermined force and temperature, surrounds an internal medium (22). The internal medium encapsulates the preformed body (12) within the container mass (20) and is capable of melting at the lesser temperatures to form a liquid barrier to gas flow therethrough. The internal medium (22) is capable of rapid hermetic sealing during the early stages of preheat. External pressure is applied by a pot die (16) and ram (14) to the entire exterior of the container mass (20) to cause the predetermined densification of the preformed body (12) by hydrostatic pressure.

Abstract: The present invention relates to a method of manufacturing widgets from components and/or particulate; and to a can for containing such components and/or particulate during the consolidation into widgets. The method of the present invention can be used to form widgets from metals, ceramics, plastics, polymers, and/or combinations thereof. The materials used to form the widgets can be in the form of particulate, pellets, shard, and/or ribbon. The method of the present invention can also be used to join widgets and/or to heal ingot cracks.

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 object of ceramic or metallic material is manufactured by isostatic pressing of a body preformed from a powder of the metallic or ceramic material, the preformed body (10) then being embedded in glass, for example in a mass of glass particles (16) in a vessel (15) which is resistant to the temperature at which the sintering of the metallic or ceramic material is carried out, the material embedding the preformed body being transferred to a melt having a surface limited by the walls of the vessel, below which surface the preformed body is located, and a pressure necessary for the isostatic pressing of the preformed body then being applied on the melt by a gaseous pressure medium.

Abstract: An object of ceramic or metallic material is manufactured by isostatic pressing of a body preformed from a powder of the metallic or ceramic material, the preformed body (10) then being embedded in glass, for example in a mass of glass particles (16) in a vessel (15) which is resistant to the temperature at which the sintering of the metallic or ceramic material is carried out, the material embedding the preformed body being transferred to a melt having a surface limited by the walls of the vessel, below which surface the preformed body is located, and a pressure necessary for the isostatic pressing of the preformed body then being applied on the melt by a gaseous pressure medium.

Abstract: A quantity of material (10), which is at less than a predetermined density, is disposed within a sealed container (12) which is, in turn, encapsulated in a pressure-transmitting (18) medium which is, in turn, placed within a pot die (20) of a press where it is restrained as a ram (24) enters the pot die (20) and applies a force to the pressure-transmitting medium (18) to densify the material within the container into a compact (10') of predetermined density. The pressure-transmitting medium (18) is characterized by a rigid interconnected ceramic skeleton structure (26) which is collapsible in response to a predetermined force and fluidizing glass (28) capable of fluidity and supported by and retained within the skeleton structure (26). The glass (28) becomes fluidic and capable of plastic flow at temperatures utilized for compaction whereas the ceramic skeleton (26) retains its configuration and acts as a carrier for the fluidic glass (28).

Abstract: Pressureless consolidation of metallic powders is achieved by sintering, in a nonoxidizing atmosphere, a blend of the metallic powder with a small amount of finely divided lithium tetraborate.

Abstract: A method for manufacturing billets intended to be subsequently machined into a desired shape by plastic deformation, as by rolling, includes the heating to a predetermined bonding temperature of powder grains enclosed in a capsule, and subjecting the capsule at the bonding temperature to a high pressure sufficient to bond the powder grains together to form a substantially solid body. The capsule is inserted at the bonding temperature into an over-sized forming cavity of a press which includes relatively movable punches, the capsule being completely surrounded within the press by a layer of heat-insulating and pressure-transmitting solid material, such as talc or the like. Thus, when the capsule is subjected to the high pressure upon operation of the press, such material serves as a pressure-transmitting medium through which pressure is applied completely against all sides of the capsule.

Abstract: A method is provided for producing a fully dense high temperature powdered metal component. This process comprises the steps of filling a centrally located mold cavity with a high temperature powder, heating the filled mold to a temperature greater than half the melting temperature of the powder in degrees centigrade and less than the melting temperature of the powder, while the cavity is maintained in a vacuum level of at least twenty microns of mercury, axially compressing the heated mold while maintaining the vacuum at a pressure of at least 345 megapascals, while restricting the mold about its lateral periphery holding the mold in a compressed state for at least 20 seconds after attaining maximum pressure, and separating the mold materials from the component. The mold is composed of a material having substantially the same flow stress throughout, and the material is able to maintain its dimensional stability in a viscoelastic state at a temperature of between approximately 950.degree. to 1300.degree. C.