Abstract: A method for preparing vapor-liquid-solid silicon carbide whisker reinforced metal matrix composites by a squeeze casting process employing a primary pressure and then a hydrostatic pressure to form the reinforced composites. The process to make the composites comprises: 1) providing VLS silicon carbide whiskers in a mold cavity; 2) introducing a molten metal into the mold cavity; 3) subjecting the molten metal and VLS silicon carbide whiskers in the cavity to a primary pressure of about 100 psi to about 2000 psi to infiltrate the whiskers with the molten metal; 4) subsequently subjecting the VLS silicon carbide whiskers infiltrated with the molten metal to a hydrostatic pressure of about 10,000 psi to about 25,000 psi to produce a fully dense mass; and 5) solidifying the metal matrix to form a composite.

Abstract: This invention relates generally to a novel method for joining at least one first self-supporting body, to at least one second self-supporting body which is similar in composition to or different in composition from said at least one first self-supporting body and to novel products which result from such joining. In some of its more specific aspects, this invention relates to different techniques for joining ceramic matrix composite bodies to other ceramic matrix composite bodies of similar characteristics and for joining ceramic matrix composite bodies to bodies which have different characteristics (e.g., metals). The ceramic matrix composite bodies of this invention are produced by a reactive infiltration of a molten parent metal into a bed or mass containing a boron source material and a carbon source material (e.g., boron carbide) and/or a boron source material and a nitrogen source material (e.g., boron nitride) and, optionally, one or more inert fillers.

Abstract: A method for producing a reinforced composite material. A molten matrix metal is heated to a temperature substantially greater than the melting point of the matrix metal. The matrix metal is poured into a mold containing a mass of reinforcing material, and an oxide layer formed from said molten matrix metal is ruptured so that the molten matrix metal infiltrates the mass of reinforcing material.

Abstract: The present invention relates to a novel method for forming metal matrix composite bodies and the novel products produced therefrom. A negative shape or cavity, which is complementary to the desired metal matrix composite body to be produced, is first formed. The formed cavity is thereafter filled with a permeable mass of filler material. Molten matrix metal is then induced to spontaneously infiltrate the filled cavity. Particularly, an infiltration enhancer and/or an infiltration enhancer precursor and/or an infiltrating atmosphere are also in communication with the filler material, at least at some point during the process, which permits the matrix metal, when made molten, to spontaneously infiltrate the permeable mass of filler material, which at some point during the processing, may become self-supporting. In a preferred embodiment, cavities can be produced by a process which is similar to the so-called lost-wax process.

Abstract: A method of infiltrating a porous ceramic compact with a molten metal to form a cermet is disclosed. A solid-phase metal is disposed on a surface of a porous ceramic compact. The surface of the porous ceramic compact is at an angle to the horizontal which is sufficient to allow molten metal formed from the solid-phase metal to rupture an oxide layer at least partially supporting the molten metal. The solid-phase metal is heated to a temperature sufficient to melt the solid-phase metal and to allow the molten metal formed to rupture the oxide layer. The molten metal flows through an opening in the metal oxide layer formed by the rupture and infiltrates the porous ceramic compact. The porous ceramic compact, containing the molten metal, is then cooled to a temperature whereby the molten metal solidifies, thereby forming a cermet.

Abstract: Process for the production of ingots of castable discontinuous metal matrix omposites by encapsulating particulate refractory material of the B.sub.4 C or SiC in a matrix metal of Li or al to form a solid master alloy, and introducing the master alloy into molten Mg or an alloy thereof, mixing and then cooling to solidify the resultant mixture and form an ingot with the refractory material substantially dispersed in the ingot.

Abstract: A method for impregnating an iron product with a hard wear-resistant material surface layer comprises providing a pattern of particles onto a high temperature adhesive layer on a sand core and casting of the iron melt around the particles so as to produce an iron product. Preferably, the pattern of particles is produced by providing a mesh plate having a desired pattern of holes and spreading the particles onto the sheet. The pattern of particles is then transferred on to the adhesive layer so as to minimize contact with the adhesive. This can be accomplished, for example, through the use of adhesive tape. Preferably, the iron product of the present invention comprises ductile iron while the wear-resistant material comprises tungsten carbide which can include about 12 wt % Co.

Abstract: A method for impregnating an aluminum product with a hard wear resistant surface area comprises providing a desired pattern of particles thereon, providing a sand core which has an high temperature adhesive layer on at least a portion thereof and transferring the pattern of particles onto the adhesive layer, in such a manner so as to minimize contact with the adhesive. After the adhesive is cured, an aluminum melt is cast around the carbides so as to produce an aluminum product having a wear resistant material surface layer. Preferably, the aluminum alloy contains about 4% by weight of copper and the wear resistant material comprises tungsten carbide containing 12 wt. % Co. In one embodiment, the particles are transferred onto the adhesive layer through the use of an adhesive tape which is used to pick up the pattern of particle and then placed upon the adhesive layer on the core surface.

Abstract: The present invention relates to a novel process for forming macrocomposite bodies and the novel bodies formed thereby. Particularly, a suitable matrix metal, typically in a molten state, is in contact with a suitable mass of filler material or preform located adjacent to, or in contact with, at least one second material in the presence of a suitable reactive atmosphere in an impermeable container, at least at some point during the process, which permits a reaction to occur between the reactive atmosphere and the molten matrix metal and/or mass of filler material or preform and/or impermeable container, thereby causing molten matrix metal to infiltrate the mass of filler material or preform due to, at least in part, the creation of a self-generated vacuum. Such self-generated vacuum infiltration occurs without the application of any external pressure or vacuum.

Abstract: A cast composite material is formed from about 5 to about 35 volume percent of particulate reinforcement, preferably silicon carbide particles, embedded in an aluminum alloy matrix having from about 8.5 to about 12.6, most preferably about 9.5 to about 11.0, weight percent silicon. The cast composite material is particularly well suited for use as a foundry alloy for remelting purposes. Other alloying elements may be added without interfering with the beneficial effects of the silicon.

Abstract: Metal and ceramic particles of various morphologies are clad with a coating from the transistion metal group consisting of silver, gold, copper, nickel, iron, cobalt, aluminum etc., or combinations thereof, to provide improved coated particles for microelectronics or metal matrix composites or other uses. Refractory metal precursor core particles, such as tungsten, molybdenum, niobium and zirconium, as examples, are provided from a composite of tungsten and copper, for example, made by pressurizing and infiltrating or liquid phase sintering of molten copper into a porous tungsten skeleton. Precursor chip particles derived from a tungsten impregnated billet are used as starter particles which may be further enhanced by cogrinding in an attritor ball mill with smaller copper particles to thereby produce an enhanced copper clad-coating of tungsten particles with predetermined percent by weight of copper and tungsten content.

Abstract: A method for producing composite materials by forming one material in a die cavity such that another material can be forced into the same die cavity and infiltrate the spaces in the first material. A method for producing a composite comprising the steps of injecting reinforcement material in a binder or suspension into a die cavity; burning off or removing the binder or suspension such that the reinforcement material remains in the die cavity; injecting liquid metal into the same die cavity such that it infiltrates the reinforcement material; solidifying the liquid metal; and removing the metal infiltrated composite material from the die cavity. An apparatus comprised of a die and a die cavity disposed inside the die. The apparatus is also comprised of a first port extending from the die cavity to the surface of the die through which reinforcement material in a binder is injected into a die cavity.

Abstract: The present invention relates to the formation of a metal matrix composite body by a spontaneous infiltration technique. Particularly, an infiltration enhancer and/or infiltration enhancer precursor can be positioned at least partially between or at an interface between a matrix metal and a filler material (or preform) which is to be infiltrated by molten matrix metal. Moreover, at least at some point during the process, an infiltrating atmosphere may be in communication with the filler material or preform and/or matrix metal.

Abstract: A method is disclosed for producing a reinforced composite material. A molten matrix metal is heated to a temperature substantially greater than the melting point of the matrix metal. The matrix metal is poured into a mold containing a mass of reincforcing material. The matrix metal is solidified.

Abstract: A metal matrix composite is formed by contacting a molten matrix alloy with a permeable mass of filler material or preform in the presence of an infiltrating atmosphere. Under these conditions, the molten matrix alloy will spontaneously infiltrate the permeable mass of filler material or preform under normal atmospheric pressures. Once a desired amount of spontaneous infiltration has been achieved, or during the spontaneous infiltration step, the matrix metal which has infiltrated the permeable mass of filler material or preform is directionally solidified. The directionally solidified metal matrix composite may be heated to a temperature in excess of the liquidus temperature of the matrix metal and quenched. This technique allows the production of spontaneously infiltrated metal matrix composites having improved microstructures and properties.

Abstract: The present invention relates to a novel process for forming net or near net-shape metal matrix composite bodies. Particularly, a molten matrix metal is in contact with a filler material or a preform in the presence of a reactive atmosphere, at least at some point during the process, which permits molten matrix metal to react, at least partially or substantially completely, with the reactive atmosphere, thereby causing molten matrix metal to infiltrate the filler material or preform due to the creation of a self-generated vacuum. Forming a glassy seal on the reaction system, the self-generated vacuum infiltration occurs without the application of any external pressure or vacuum. The molten matrix metal infiltrates the filler material up to at least a portion of a provided barrier means.

Abstract: The present invention relates to a novel method for forming metal matrix composite bodies. Particularly, a permeable mass of filler material is formed into a preform. An infiltration enhancer and/or an infiltration enhancer precursor and/or an infiltrating atmosphere are also in communication with the preform, at least at some point during the process, which permits molten matrix metal to spontaneously infiltrate the preform when the preform is placed into the molten matrix metal. A means for maintaining the preform at least partially below the surface of the molten matrix metal can also be utilized.

Abstract: This invention relates generally to a novel method for joining at least one first self-supporting body, to at least one second self-supporting body which is similar in composition to or different in composition from said at least one first self-supporting body and to novel products which result from such joining. In some of its more specific aspects, this invention relates to different techniques for joining ceramic matrix composite bodies to other ceramic matrix composite bodies of similar characteristics and for joining ceramic matrix composite bodies to bodies which have different characteristics (e.g., metals). The ceramic matrix composite bodies of this invention are produced by a reactive infiltration of a molten parent metal into a bed or mass containing a boron source material and a carbon source material (e.g., boron carbide) and/or a boron source material and a nitrogen source material (e.g., boron nitride) and, optionally, one or more inert fillers.

Abstract: A process for the manufacture of a master cylinder for hydraulic brake units of automotive vehicles. The starting material is a pasty material which is between solid and liquid. In the course of the casting procedure, thin material wall thicknesses are created in the regions of intended openings of the master cylinder, such as the breather bore (14) and the intake bore (5). The floating membrane (12) which forms during the casting process is removed by mechanical machining to open the duct which functions as the intake bore. The breather bore (14) which functions as the compensation bore is formed by a stamping operation.

Abstract: The present invention relates to the use of a gating means in combination with a spontaneous infiltration process to produce a metal matrix composite body. Particularly, a permeable mass of filler material or a preform is spontaneously infiltrated by molten matrix metal to form a metal matrix composite body. A gating means is provided which controls or limits the areal contact between molten matrix metal and the filler material or preform. The use of a gating means provides for control of the amount of matrix metal which can contact the preform or filler material, which may result in less machining of a formed metal composite body compared with a similar metal matrix composite body made without a gating mean. Moreover, the use of a gating means ameliorates the tendency of a formed metal matrix composite body to warp due to the contact between the formed composite body and matrix metal carcass.

Abstract: A method for forming a metal matrix composite within a mold of investment material. The method comprises the steps of forming a preform mixture of liquid flow medium, binding agent and reinforcement into the desired shape of a metal matrix composite. Then, allowing the preform mixture to solidify into desired shape. Next, encasing the preform mixture within investment material. Then, heating the preform mixture at a controlled rate which first allows any fluid, such as water, to evaporate, then allows removal of the flow medium. Next, sintering the remaining reinforcement material and binder to form a solid preform. Then, forcing molten metal under pressure into said preform. Next, solidifying the molten metal to form a metal matrix composite in the shape of this preform; and removing the investment material from metal matrix composite. Additionally, there is a method comprising the steps of connecting a preform, which has been previously prepared for infiltration of molten metal, to a sprue system.

Abstract: A porous preform is placed within a permanent, nonporous, thin walled mold chamber. The mold chamber is disposed within a pressure vessel. A material is placed in a crucible of the pressure vessel. The pressure vessel is evacuated through a snorkel fluidically connected to the mold chamber. There is means for cooling the snorkel in thermal communication with the snorkel. The material is melted within the crucible. The crucible is placed in fluidic communication with the mold chamber such that the melted material seals the inside of the mold chamber from the pressure vessel to isolate a vacuum within the mold chamber.

Abstract: The apparatus for casting comprises a pressure vessel and a device for evacuating and pressurizing the vessel. The evacuating and pressurizing device is in fluidic connection with the vessel. The apparatus is also comprised of a chamber disposed in the pressure vessel within which material is melted. There is a mold with a passage such that the melted material in the chamber can be forced down into the mold through the passage as the pressurizing device pressurize the vessel. The passage contains a filter such that the melted material is prevented from entering the interior of the mold prior to pressurization. Additionally, the apparatus is comprised of a device for heating material in the chamber and the mold such that material is melted in the chamber and stays melted as it is forced down into mold while the pressurizing device pressurizes the vessel. The heating device is disposed in the vessel.

Abstract: A method is disclosed as an improvement to the art of treating local areas of powdered metal parts which have been afflicted with stress concentrations due to applied loads, or have produced adverse frictional characteristics caused by sliding or rolling wear, etc. The method is directed to improving the material properties of these localized areas by placing a suitable metal adjacent the affected area and to apply heat in concentrated form solely upon the metal and the area to affect infiltration of the metal at that area.

Abstract: This invention relates generally to a novel method of manufacturing a composite body and to novel products made thereby. More particularly, the invention relates to a method of producing a self-supporting composite body comprising one or more boron-containing compounds, e.g., a boride or a boride and carbide, by reactive infiltration of molten parent metal into a bed or mass containing boron carbide, and, optionally, one or more inert fillers and permitting residual or excess parent metal to remain bonded to the formed self-supporting composite body. The residual or excess metal is used to form a bond between the formed composite body and another body (e.g., a metal body, a ceramic body, or another composite body). In addition, this invention related to alternative methods of disposing metal on at least one surface of the above-described composite bodies (such as sputtering, CVD, etc.) to permit the composite bodies to be bonded to another body.

Abstract: A preshaped body of ceramic fibers is placed into a mold and molten aluminum-silicon alloy material is charged into the mold. The pressure is increased in a controlled manner so that the shaped fibrous body is penetrated by the molten material and the final pressure is maintained until the molten material has entirely solidified. To permit the use of a distinctly lower final pressure, the shaped fibrous body before it is placed into the mold is impregnated with an aqueous solution of CuSO.sub.4, dried at a temperature from 60.degree. to 90.degree. C. and heated to a temperature from 500.degree. to 1200.degree. C., preferably 850.degree. to 1000.degree. C., and the molten material is caused to solidify under a final pressure from 10 to 100 bars.

Abstract: A cast composite material is made from particles and a matrix alloy of preselected composition that is difficult to wet to the particles. A wetting alloy having a composition that readily wets the particles is first mixed with the particles under conditions that wet the wetting alloy to the particles. The wetting alloy is selected so that is has no alloying elements in excess of that in the preselected matrix alloy, and preferably with wettability inhibiting elements reduced. After wetting and mixing have been achieved, the remaining alloying ingredients are added to the melt to adjust the matrix to the desired composition. The approach is applicable to cast composite materials containing both reactive and nonreactive particles. (aluminum matrix with silicon additions).

Abstract: A cast composite material is prepared from a modified aluminum-containing matrix and reinforcement particles mixed into the matrix. From about 15 to about 130, preferably from about 20 to about 50, parts per million of an element, preferably beryllium, that forms a more stable oxide than magnesium oxide is included in the matrix alloy. The stable-oxide-forming element reduces the amount and thickness of the aluminum oxide and other oxides formed at the surface of the melt, which otherwise may be mixed into the melt to cause microstructural irregularities in the matrix of the cast composite material.

Abstract: A method for manufacturing a ceramic reinforced piston and a molding machine therefor. A composite product composed of a cast product made of aluminum alloy or the like and shaped inorganic short fiber, particles or the like is obtained so that mechanical strength, wear resistance, heat resistance and the like of such composite product can be increased. Furthermore, mass production of such composite products becomes possible. A suitable amount of ceramic particles or a shaped inorganic short fiber is introduced in a casting mold, a molten metal such as an aluminum alloy and the like is then poured in the casting mold, and an upper punch is suitably pushed down on the molten metal to pressurize such molten metal in the casting mold. Push rams are additionally introduced laterally into the mold before or during the pouring of the molten metal to compensate for any shortage of molten metal and assure the metal penetrates the particles of fiber. The metal solidifies under pressure.

Abstract: A mixture of ceramic particles (such as SiC particles) with metallic powder (such as iron-base particles, e.g., stainless steel particles) is placed in a predetermined position of an internal wall of a mold and a molten metal (e.g., molten iron-base metal, particularly molten cast iron) is poured into the mold. In this manner a wear-resistant layer is formed in a necessary portion on a surface of the casting at the same time when casting is conducted.

Abstract: The present invention relates to the formation of a macrocomposite body by spontaneously infiltrating a permeable mass of filler material or a preform with molten matrix metal and bonding the spontaneously infiltrated material to at least one second material such as a ceramic or ceramic containing body and/or a metal or metal containing body. Particularly, an infiltration enhancer and/or infiltration enhancer precursor and/or infiltrating atmosphere are in communication with a filler material or a preform, at least at some point during the process, which permits molten matrix metal to spontaneously infiltrate the filler material or preform. Moreover, prior to infiltration, the filler material or preform is placed into contact with at least a portion of a second material such that after infiltration of the filler material or preform, the infiltrated material is bonded to the second material, thereby forming a macrocomposite body.

Abstract: Tubes or other symmetrical shapes are formed of composite materials, such silicon carbide and aluminum, by spin casting. The reinforcing material can be precast into a billet or bar of the matrix metal, remelted and introduced into a spinning mold. Tubes can be produced with walls having differing amounts of reinforcing materials in the tube wall. Castings can be obtained having a uniform distribution of a reinforcement in a matrix metal.

Abstract: A method for making a fiber reinforced composite article includes placing in a forming mold article cavity a preform which includes at least a fiber reinforcement arrangement, such as stacked piles of resin bonded sheets. Closure of the mold defines a matrix reservoir for excess matrix material in fluid flow relationship with the article cavity. Gas pressure applied to the excess matrix material while in the fluid condition forces that material back into the article cavity to nominally eliminate voids, pores and other internal and surface discontinuities from the article.

Abstract: The present invention relates to a novel method for forming metal matrix composite bodies and novel products produced by the method. Particularly, a permeable mass of filler material or a preform has included therein at least some matrix metal powder. Moreover, an infiltration enhancer and/or an infiltration enhancer precursor and/or an infiltrating atmosphere are in communication with the filler material or a preform, at least at some point during the process, which permits molten matrix metal to spontaneously infiltrate the filler material or preform. The presence of powdered matrix metal in the preform or filler material reduces the relative volume fraction of filler material to matrix metal.

Abstract: A metal matrix composite is formed by contacting a molten matrix alloy with a permeable mass of filler material or preform in the presence of an infiltrating atmosphere. Under these conditions, the molten matrix alloy will spontaneously infiltrate the permeable mass of filler material or preform under normal atmospheric pressures. Once a desired amount of spontaneous infiltration has been achieved, or during the spontaneous infiltration step, the matrix metal which has infiltrated the permeable mass of filler material or preform is directionally solidified. This technique allows the production of spontaneously infiltrated metal matrix composites having improved microstructures and properties.

Abstract: The present invention relates to the formation of a metal matrix composite body by a spontaneous infiltration technique. Particularly, an infiltration enhancer and/or infiltration enhancer precursor can be positioned at least partially between or at an interface between a matrix metal and a filler material (or preform) which is to be infiltrated by molten matrix metal. Moreover, at least at some point during the process, an infiltrating atmosphere may be in communication with the filler material or preform and/or matrix metal.

Abstract: The present invention relates to a novel method for forming metal matrix composite bodies and the novel products produced therefrom. A negative shape or cavity, which is complementary to the desired metal matrix composite body to be produced, is first formed. The formed cavity is thereafter filled with a permeable mass of filler material. Molten matrix metal is then induced to spontaneously infiltrate the filled cavity. Particularly, an infiltration enhancer and/or an infiltration enhancer precursor and/or an infiltrating atmosphere are also in communication with the filler material, at least at some point during the process, which permits the matrix metal, when made molten, to spontaneously infiltrate the permeable mass of filler material, which at some point during the processing, may become self-supporting. In a preferred embodiment, cavities can be produced by a process which is similar to the so-called lost-wax process.

Abstract: The present invention relates to the use of a gating means in combination with a spontaneous infiltration process to produce a metal matrix composite body. Particularly, a permeable mass of filler material or a preform is spontaneously infiltrated by molten matrix metal to form a metal matrix composite body. A gating means is provided which controls or limits the areal contact between molten matrix metal and the filler material or preform. The use of a gating means provides for control of the amount of matrix metal which can contact the preform or filler material, which may result in less machining of a formed metal matrix composite body compared with a similar metal matrix composite body made without a gating means, moreover, the use of a gating means ameliorates the tendency of a formed metal matrix composite body to warp due to the contact between the formed composite body and matrix metal carcass.

Abstract: The present invention relates to a novel method for forming metal matrix composite bodies and novel metal matrix composite bodies produced thereby. Particularly, a polycrystalline oxidation reaction product of a parent metal and an oxidant is first formed. The polycrystalline oxidation reaction product is thereafter comminuted into an appropriately sized filler material which can be placed into a suitable container or formed into a preform. The filler material or preform of comminuted polycrystalline oxidation reaction product is thereafter placed into contact with a matrix metal alloy in the presence of an infiltration enhancer, and/or an infiltration enhancer precursor and/or an infiltrating atmosphere, at least at some point during the process, whereupon the matrix metal alloy spontaneously infiltrates the filler material or preform. As a result of utilizing comminuted or crushed polycrystalline oxidation reaction product, enhanced infiltration (e.g., enhanced rate or amount) is achieved.

Abstract: The present invention relates to the formation of a metal matrix composite body by the spontaneous infiltration of a molten matrix metal into a three-dimensionally interconnected material. Moreover, the three-dimensionally interconnected material may contain filler material within at least a portion of its porosity. Particularly, an infiltration enhancer and/or an infiltration enhancer precursor and/or an infiltrating atmosphere are in communication with a filler material and/or a three-dimensionally interconnected material and/or a matrix metal at least at some point during the process, which permits molten matrix metal to spontaneously infiltrate the three-dimensionally interconnected material and any filler material contained within at least a portion of the porosity of the three-dimensionally interconnected material.

Abstract: The present invention relates to a novel method for forming a metal matrix composite body, and products produced thereby. Particularly, a permeable mass of filler material is formed into a preform, the preform having at least a portion thereof which contains a cavity. An infiltration enhancer and/or an infiltration enhancer precursor and/or an infiltrating atmosphere are also in communication with the preform, at least at some point during the process, which permits molten matrix metal to spontaneously infiltrate the preform when the preform is placed into molten matrix metal. An infiltrating atmosphere is provided in communication with the cavity in the preform for at least a portion of the process, and molten matrix metal is contacted with an exterior portion of the preform, such that molten matrix metal will spontaneously infiltrate the preform from an exterior surface thereof toward the cavity.

Abstract: The present invention relates to forming a a metal matrix composite between at least two bodies having a similar or a different chemical composition, the metal matrix composite functioning as a bonding means which to bonds or fixes the bodies together. Particularly, a metal matrix composite is produced by a spontaneous infiltration technique by providing a filler material or preform with an infiltration enhancer and/or an infiltration enhancer precursor and/or and infiltrating atmosphere, which are in communication with the filler material or preform at least at some point during the process. Molten matrix metal then spontaneously infiltrates the filler material or preform, whereby the metal matrix composite serves to bond together two or more bodies.

Abstract: The present invention relates to a novel method for forming metal matrix composite bodies, and the metal matrix composite bodies produced according to the novel method. Particularly, a permeable mass of filler material is formed into a preform by first forming a negative cavity in a matrix metal and thereafter placing said permeable mass of filler material into said cavity. An infiltration enhancer and/or an infiltration enhancer precursor and/or an infiltrating atmosphere are also in communication with the filler material, at least at some point along the process, which permit the matrix metal, when made molten, to spontaneously infiltrate the permeable mass of filler material, which at some point during the processing, may become self-supporting.

Abstract: The present invention relates to the formation of a metal matrix composite body by a spontaneous infiltration technique and thereafter thermo-forming the produced metal matrix composite body. Particularly, an infiltration enhancer and/or an infiltration enhancer precursor and/or an infiltrating atmosphere are in communication with a filler material or a preform, at least at some point during the process, which permits molten matrix metal to spontaneously infiltrate the filler material or preform. After formation of the metal matrix composite body, the body is subjected to a thermo-forming technique such as rolling, extruding, die casting, pressing, etc.

Abstract: A process for the casting of shaped objects by subjecting a mould to a centrifugal acceleration directed to the bottom of the mould and introducing a molten pure metal or alloy into the mould, wherein a dispersed filler is placed before adding the melt, which filler is retained immovably during the addition of the melt by using a cover plate.

Abstract: The present invention relates to a novel method for forming metal matrix composite bodies. Particularly, a permeable mass of filler material is formed into a preform. An infiltration enhancer and/or an infiltration enhancer precursor and/or an infiltrating atmosphere are also in communication with the preform, at least at some point during the process, which permits molten matrix metal to spontaneously infiltrate the preform when the preform is placed into the molten matrix metal. A means for maintaining the preform at least partially below the surface of the molten matrix metal can also be utilized.

Abstract: A novel infiltration alloy comprises about 5 to 65% by weight of manganese, up to about 35% by weight of zinc, and the balance copper. Preferably, the infiltration alloy comprises 20% by weight of manganese, 20% by weight of zinc, and the balance copper. The infiltration alloy is useful in the manufacture of matrix bodies such as matrix drill bit bodies. A method for the manufacture of a matrix body comprises forming a hollow mold for molding at least a portion of the matrix body, positioning diamond cutting elements in the mold, packing at least a part of the mold with a powder matrix material, infiltrating the matrix material with the novel infiltration alloy in a furnace to form a mass, and allowing the mass to solidify into an integral matrix body. Because the novel infiltration alloy permits infiltration to be carried out at temperatures below about 1050.degree. C., many diamond cutting elements which begin to deteriorate at temperatures above 1000.degree. C.

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: The present invention relates to a novel method for forming metal matrix composite bodies. Particularly, a permeable mass of filler material is formed into a preform. The preform material can then be floated onto the surface of or into a matrix metal alloy, whereupon the matrix metal alloy spontaneously infiltrates the preform. After substantial complete infiltration of the preform, the preform begins to at least partially sink into the matrix metal alloy supply. The matrix metal which has infiltrated the preform is then allowed to cool, thus forming a metal matrix composite body.

Abstract: The present invention relates to a novel method for forming metal matrix composite bodies. A permeable mass of filler material is spontaneously infiltrated by a molten matrix metal. Particularly, an infiltration enhancer and/or infiltration enhancer precursor and/or an infiltrating atmosphere are in communication with the filler material, at least at some point during the process, which permits molten matrix metal to spontaneously infiltrate the filler material. After infiltration has been completed to a desired extent, additional matrix metal is added to that matrix metal which has spontaneously infiltrated the filler material to result in a suspension of filler material and matrix metal, said suspension having a lower volume fraction of filler relative to matrix metal. The matrix metal then can be permitted to cool in situ or the mixture of matrix metal and filler material can be poured into a second container as a casting process to form a desired shape which corresponds to the second container.