Abstract: Boron carbide ceramics produced by spark sintering methods have more desirable mechanical properties than conventionally produced carbides. The boron carbide ceramics include amorphous boron, amorphous carbon, and Al2O3 powder as a sintering aid. The boron carbides may also contain a carbon nano fiber in a nearly homogeneously dispersed state. The sintered compact has a relative density of a boron carbide ceramic of approximately not less than 99%. The boron carbide ceramics are prepared preferably by subjecting a mixed powder of the starting raw materials and the carbon nano fiber to simultaneous synthesis and sintering using the spark plasma sintering method.

Abstract: A clay-pulp mixture is prepared by blending a predetermined ratio of clay and wood pulp derived from alpha virgin cellulose in dry form, moistening the mixture homogeneously by adding water and continuing to blend until a malleable consistency is achieved. Air is extracted from the moist mixture, and solid blocks formed for storage and delivery to end-users.

Abstract: A coherent nonwoven fibrous web comprises directly formed elastic fibers that have a molecular orientation sufficient to provide a birefringence number of at least 1×10?5 and preferably at least 1×10?2. The web can be made by a method that comprises a) extruding filaments of elastic-fiber-forming material; b) directing the filaments through a processing chamber in which gaseous currents apply a longitudinal stress to the filaments that attenuates and draws the filaments; c) maintaining the filaments at their orienting temperature while the filaments are under attenuating and drawing stress for a sufficient time for molecules within the filaments to become oriented along the length of the filaments; d) cooling the filaments to their orientation-locking temperature while the filaments are under attenuating and drawing stress and further cooling the filaments to a solidified fiber form; and e) collecting the solidified fibers as a fibrous nonwoven web.

Abstract: A method for the production of components made of ceramic-matrix composite material, in the fields of aerospace engines and turbines and turbine systems and plants; according to the method, a preform of ceramic fibres is shaped and set in a draining mould, for example made of plaster; the fibres of the preform are impregnated with a suspension of ceramic powders, the liquid of which is drained by capillarity from the draining mould; simultaneously to draining, a suspension of ceramic powders is infiltrated between the fibres of the preform so as to fill the empty space left by the drained liquid; at the end of the steps of draining/infiltration a body is obtained with a solidified or compacted porous matrix, which is removed from the draining mould and is sintered.

Abstract: Inorganic fibers consisting substantially of silicon, carbon, oxygen and a transition metal, having a fiber size of no greater than 2 ?m and having fiber lengths of 100 ?m or greater.

Abstract: A pasty molding material is divided by a process wherein, for the division, the pasty molding material is brought into contact with at least on stream containing at least one fluid medium.

Abstract: A method is provided for producing insulation materials and insulation for high temperature applications using novel castable and powder-based ceramics. The ceramic components produced using the proposed process offers (i) a fine porosity (from nano-to micro scale); (ii) a superior strength-to-weight ratio; and (iii) flexibility in designing multilayered features offering multifunctionality which will increase the service lifetime of insulation and refractory components used in the solid oxide fuel cell, direct carbon fuel cell, furnace, metal melting, glass, chemical, paper/pulp, automobile, industrial heating, coal, and power generation industries. Further, the ceramic components made using this method may have net-shape and/or net-size advantages with minimum post machining requirements.

Abstract: A ceramic matrix composite with a ceramic matrix and a gradient layering of coating on ceramic fibers. The coating typically improves the performance of the composite in one direction while degrading it in another direction. For a SiC-SiC ceramic matrix composite, a BN coating is layered in a gradient fashion or in a step-wise fashion in different regions of the article comprising the ceramic. The BN coating thickness is applied over the ceramic fibers to produce varying desired physical properties by varying the coating thickness within differing regions of the composite, thereby tailoring the strength of the composite in the different regions. The coating may be applied as a single layer as a multi-layer coating to enhance the performance of the coating as the ceramic matrix is formed or infiltrated from precursor materials into a preform of the ceramic fibers.

Abstract: A method of producing a fiber-reinforced carbide-ceramic component includes producing a carbonaceous article from at least one unidirectional tape by pyrolysis, infiltrating the carbonaceous article with carbide former, and coating the at least one unidirectional tape with a coating material being volatile in pyrolysis and/or providing the at least one unidirectional tape with a transverse thread system including transverse threads composed of a material being volatile in pyrolysis. A fiber-reinforced carbide ceramic component is also provided.

Abstract: A process of manufacturing core-sheath composite fiber includes the steps of: preparing hollow fiber in a form of filament of which some parts forms communicating pores from an outer surface of the fiber to a hollow portion thereof, or in a form of filament segment with open ends; sealing adjacent porous parts or open ends of the same filament respectively in pressure containers and vacuum containers; adding filling materials into pressure containers, and keeping the porous parts or open ends completely immersed in the filling materials; pressurizing the pressure containers using compressed gas, and evacuating the vacuum containers, then the filling materials being absorbed through the communicating pores or opens into the hollow portion of the fiber. During the process of the present invention to manufacture core-sheath composite fiber, most areas of outer surface of the fiber do not contact the filling materials, thus most areas of the outer surface is clean, which is advantageous for post treating or use.

Abstract: In the manufacture of slabs and panels of ceramic material according to the vacuum vibrocompaction method described in Italian patent 1,311,858, the initial mix is formed using ceramic having the form of sands having a grain size of less than 2.5 mm, preferably less than 1 mm, and ceramic powders, together with a binding additive in the form of an aqueous solution consisting of sodium silicate in a concentration greater than 24° Baumé, fibers of high-melting transparent inorganic material, preferably high-melting glass, also being added to the mix. The slabs obtained have an improved mechanical strength, a reduced porosity and improved aesthetic properties, in addition to being free from cracks and microscopic fissures.

Abstract: A method of forming a ceramic matrix composite (CMC) article (30) or a composite article (60) that minimizes the risk of delaminations while simultaneously maintaining a desired degree of porosity in the material. A pressure P applied against a surface of the article during a sintering process is controlled to be high enough to resist a separation force between the plies (66) of the CMC material (62) caused by anisotropic shrinkage of the material and/or to resist a separation force caused by differential shrinkage between the CMC material and an adjoined monolithic ceramic material (64). The pressure is also controlled to be low enough to avoid undue consolidation of the materials and to provide a desired degree of porosity in the sintered article. The pressure may be applied by delta-alpha tooling, and it may be varied verses the time of the sintering heating and/or across the article surface.

Abstract: The present invention provides a liquid absorbing member for absorbing excessive ink components from an ink image formed on a recording medium by an ink jet recording method, in which the liquid absorbing member contains fibrous matter, and the fiber thickness of fibers composing the fibrous matter is in a range of about 0.01 to 100 dtex. The fibrous matter preferably contains fibers having a fiber diameter in a range of about 0.5 to 10 ?m, and fibers composing the fibrous matter are preferably polyester fibers. The invention also provides an ink jet recording apparatus comprising a printhead and the liquid absorbing member.

Abstract: A method of constructing a hollow fiber reinforced structure is disclosed. A spindle structure is provided for defining a preform shape. A resin binder or matrix is applied to a fiber material and the fiber material is placed around the spindle structure to create a hollow preform having a shape defined by the spindle structure. The preform structure is reshaped into a desired shape defined by the interior surface of a hollow mold and the exterior surface of an expandable insert structure. The reshaped preform structure is further conditioned to create a finished part. A hollow filament wound ceramic matrix composite airfoil suitable for use in a gas turbine engine may be constructed using the disclosed method.

Abstract: This invention deals with a family of inorganic-organic hybrid, melt-extruded filaments having variable cross-sectional geometry with a cross-sectional area ranging between 100 ?2 and 4 mm2, wherein the inorganic component comprises at least 10 weight percent of the total system and is present as dispersed micro-/nanoparticles in an organic absorbable or non-absorbable matrix representing no more than 90 weight percent. Hybrid filaments are particularly useful for the production of absorbable/disintegratable coil components of an absorbable/disintegratable endoureteral stent and radiopaque surgical markers or sutures.

Abstract: A method for producing composite ceramic material is provided wherein a core ceramic structure is produced and simultaneously enveloped with a sleeve of similar material.

Abstract: The present invention provides sintered polymeric materials and methods of making the same which are useful in a variety of applications. In one embodiment, the present invention provides a sintered polymeric material comprising at least one plastic and at least one elastomer.

Abstract: Carbon particles, such as, carbon fibrils and carbon nanotube molecules, may be assembled into substantially pure aligned fibers by a) dispersing the carbon particles within a curable liquid, b) aligning the carbon particles by flowing the mixture of curable liquid and carbon particles down a tapering tube, and c) curing the flowing mixture of curable liquid and carbon particles in the general vicinity of the end of the tapering tube to form a fiber. The curable liquid may be cured using ultraviolet light. The solidified mixture may be further processed by d) heating the fiber so as to cause the volatile elements of the solidified curable liquid portion to substantially dissipate from the fiber, e) twisting the fiber to increase its density, f) heating the fiber to sinter the carbon particles within the fiber, and g) cladding the fiber. The resulting fiber may then be spooled onto a take-up drum.

Abstract: This invention relates to a coated fabric and a method of making the same, and laminates and articles comprising the coated fabric. The fabric comprises a woven substrate having fiber volume fraction of at least 70 percent and non-meltable, rigid rod, high strength filaments having angular cross sections created by densifying the woven substrate. The coated fabrics and laminates are especially useful in rigid armor applications.

Abstract: Processes for mechanically fabricating two and three-dimensional fibrous monolith composites include preparing a fibrous monolith filament from a core composition of a first powder material and a boundary material of a second powder material. The filament includes a first portion of the core composition surrounded by a second portion of the boundary composition. One or more filaments are extruded through a mechanically-controlled deposition nozzle onto a working surface to create a fibrous monolith composite object. The objects may be formed directly from computer models and have complex geometries.

Abstract: Fibrous structures, especially fibrous structures that exhibit softness and strength, sanitary tissue products employing such fibrous structures and methods for making such fibrous structures are provided. More particularly, fibrous structures that have a long fiber furnish that comprises less than 10% by weight of fibers having a coarseness of less than 20 mg/100 m, sanitary tissue products employing such fibrous structures and methods for making such fibrous structures are provided.

Abstract: A preformed of SiC fiber, which is coated with one or more of C, BN and SiC, is impregnated with a slurry, which suspends fine SiC powder and a sintering additive therein. The impregnated preform is hot-pressed at 1600-1800° C. with a pressure of 10 MPa or more. The sintering additive may be one or more of Al2O3, Y2O3, SiO2 and CaO. The slurry may futher contain a silicone polymer selected from polycarbosilane, polyvinylsilane and polymethylsilane. Reaction of SiC fiber with a matrix is inhibited by the coating, so as to manufacture a SiC fiber-reinforced SiC-matrix composite remarkably improved in mechanical properties.

Abstract: Faux fibers, more particularly faux fibers including a dye, methods for making such faux fibers and fibrous structures employing such faux fibers are provided.

Abstract: A green body ceramic matrix composite material (30) is formed using ceramic fibers (32) in an intermediate state disposed in a green body ceramic matrix material (34). The fibers may be in either a dry but unfired (green) condition or in a partially fired condition. Selective control of the degree of pre-firing (pre-shrinkage) of the fibers may be used to control the level of residual stresses within the resulting refractory material resulting from differential shrinkage of the fibers and the matrix material during processing of the composite material.

Abstract: A shaped composite material for braking applications can be produced by a method comprising the steps of: a) providing a mixture comprising bundles of filaments constituted substantially by carbon and having lengths no greater than 30 mm and an organic binder in a mould of the said shape and, at the same time, incorporating in the mixture a plurality of reinforcing fibres which extend along the shape in a manner such as to prevent the propagation of cracks, b) forming the mixture comprising the reinforcing fibres to produce a semi-finished product, c) subjecting the semi-finished product to a first firing at a temperature such as substantially to bring about pyrolysis of the organic binder and to a second firing in the presence of silicon.

Abstract: Methods are provided for producing a ceramic matrix composite by slurry infiltration. The methods involve placing a desized ceramic cloth lay-up into a non-ceramic cloth bag, sealing the bag to form a bagged ceramic preform, infiltrating the bagged ceramic preform with a ceramic-containing slurry, and sintering the preform to convert the slurry to a ceramic while decomposing the non-ceramic bag. The methods of the present invention maximize slurry infiltration of the ceramic cloth tow bundle while minimizing damage to the ceramic cloth.

Abstract: Carbon-silicon carbide brake preforms are manufactured by carbonizing a blend of carbon (e.g., polyacrylonitrile) fibers and thermosetting pitch resin, optionally along with a lubricant such as graphite,.to provide an intermediate product having open porosity and subsequently filling the pores of the intermediate product with silicon by a melt infiltration process. Molded articles that consist principally of carbon, that have relatively high strength and resistance to decomposition by frictional heat, and that are suitable for melt infiltration with silicon, are produced by, e.g.

Abstract: Methods for consolidation and densification of fibrous monolith composite structures are provided. Consolidation and densification of two- and three-dimensional fibrous monolith components having complex geometries can be achieved by pressureless sintering. The fibrous monolith composites are formed from filaments having at least a first material composition generally surrounded by a second material composition. The composites are sintered at a pressure of no more than about 30 psi to provide consolidated and densified fibrous monolith composites.

Abstract: A process for producing a continuous alumina fiber blanket by heat treating an alumina fiber precursor formed from a spinning solution containing an aluminum compound, by using a specific high-temperature furnace capable of high-temperature heat treatment. According to this process, a continuous sheet (W) of alumina fiber precursor formed from a spinning solution containing an aluminum compound is supplied continuously into a high-temperature furnace and subjected to heat treatment while being conveyed in one direction by plural conveying mechanisms (2, 3) disposed in said high-temperature furnace. In this operation, the speed of said conveying mechanisms is reduced progressively in the direction of conveyance in correspondence to the rate of heat shrinkage of the continuous sheet (W) of alumina fiber precursor, thereby to lessen fiber crush in the alumina fiber precursor and obtain a continuous alumina fiber blanket with uniform thickness and high bulk density as well as high strength.

Abstract: A modified alkali silicate composition for forming an inorganic network matrix. The modified alkali silicate matrix is made by reacting an alkali silicate (or its precursors such as an alkali hydroxide, a SiO2 source and water), an acidic inorganic composition, such as a reactive glass, water and optional fillers, additives and processing aids. An inorganic matrix composite can be prepared by applying a slurry of the modified aqueous alkali silicate composition to a reinforcing medium and applying the temperature and pressure necessary to consolidate the desired form. The composite can be shaped by compression molding as well as other known fabrication methods. A notable aspect of the invention is that, although composite and neat resin components prepared from the invention can exhibit excellent dimensional stability to 1000° C. and higher, they can be prepared at the lower temperatures and pressures typical to organic polymer processing.

Abstract: An improved, efficient, and regenerable exhaust emission filter and filter system are provided which incorporate the use of an inorganic, non-woven fiber filter element. The filter is able to capture exhaust pollutants and particulates through the interwoven nature of the filter element and due to area enhancements applied to the filter element including microscopic enhancements. The filter has an improved life and is able to combust a greater percentage of trapped particulates due to the high temperatures the filter element can withstand. The filter element if formed from a non-woven fiber block which is machined or shaped into a filter foundation. The filter element can have a multitude of coatings and catalysts applied and can be wrapped in insulation and a casing. The improved exhaust emission filter is particularly useful for diesel engine exhausts.

Abstract: A process for continuous composite coextrusion comprising: (a) forming first a material-laden composition comprising a thermoplastic polymer and at least about 40 volume % of a ceramic or metallic particulate in a manner such that the composition has a substantially cylindrical geometry and thus can be used as a substantially cylindrical feed rod; (b) forming a hole down the symmetrical axis of the feed rod; (c) inserting the start of a continuous spool of ceramic fiber, metal fiber or carbon fiber through the hole in the feed rod; (d) extruding the feed rod and spool simultaneously to form a continuous filament consisting of a green matrix material completely surrounding a dense fiber reinforcement and said filament having an average diameter that is less than the average diameter of the feed rod; and (e) depositing the continuous filament into a desired architecture which preferably is determined from specific loading conditions of the desired object and CAD design of the object to provide a green fiber rei

Abstract: A modified alkali silicate composition for forming an inorganic network. The modified alkali silicate matrix is made by reacting an alkali silicate (or its precursors such as an alkali hydroxide, a SiO2 source and water), an acidic oxoanionic compound such as phosphoric acid, water and optionally one or more multivalent cation(s) selected from Groups 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 or 16 of the periodic table such as an alkaline earth salt, water and optional processing aids. An inorganic matrix composite can be prepared by applying a slurry of the modified aqueous alkali silicate composition to a reinforcing medium and curing the composite at a temperature from about 15° C. up to 1000° C. and a pressure of up to 20,000 psi for typical high-performance organic polymer processing (temperatures about 15° C. to about 200° C. and pressures <200 psi). The composite can be shaped by compression molding as well as other known fabrication methods.

Abstract: A fiber glass mat containing a novolac resin having an acid solubility of at least about 35 wt. percent is especially useful for bonding to a light weight fibrous or foam web or board, such as a polymer fiber web. A method of making the mat by wet laying a slurry containing the fiber and the novolac resin particles and then further adding an aqueous solution or slurry containing a crosslinking agent for the novolac resin and a laminate containing the fiber glass mat are disclosed.

Abstract: There are provided a high-strength zirconia-containing inorganic fiber having excellent alkali resistance, oxidation resistance, catalyst function and/or catalyst-carrying function and a process for the production thereof. The zirconia-containing inorganic fiber is a fiber which is formed of a composite oxide phase comprising a first phase mainly formed of a silica component or silicon carbide and a second phase formed of zirconia, and it is characterized in that the ratio of Zr slopingly increases toward the surface layer of the fiber.

Abstract: A diesel particulate filter comprising a plugged, wall-flow honeycomb filter body composed of cordierite and having a plurality of parallel end-plugged cell channels traversing the body from a frontal inlet end to an outlet end thereof, wherein the filter exhibits a CTE (25-800° C.) of less than 13×10−7/° C., a bulk filter density of less than 0.60 g/cm3, a median pore diameter, d50, of less than 25 micrometers, a porosity and pore size distribution that satisfy the relationship Pm≦3.75, wherein Pm is equal to 10.2474{1/[(d50)2(% porosity/100)]}+0.0366183(d90)−0.00040119(d90)2+0.468815(100/% porosity)2+0.0297715(d50)+1.61639(d50−d10)/d50, wherein d10, and d90 are pore diameters at 10% and 90% of the pore size distribution on a volumetric basis, and d10<d50<d90. A method of making the same is also provided.

Abstract: A process for producing a fiber-reinforced, ceramic structural component comprising high-temperature resistant fibers which are reaction-bonded to a matrix of silicon carbide comprises the steps of coating bundles of fibers with pyrolysable binder and solidifying the binder, producing mixtures of fiber bundles, fillers and binders, pressing the mixtures to produce a pressed body, pyrolysing the pressed body under the exclusion of oxygen to form a porous, carbon-containing preform, infiltrating the preform with a silicon melt to form the silicon carbide matrix, in which various pressing compounds are produced, which contain fibers of different quality and in different proportions and different coatings. These pressing compounds are arranged at different levels and in different spatial directions in the press mould during the filling of the press mould. After the pressing, the regions produced in this way are retained in the press mould.

Abstract: The invention relates to methods for fabricating ceramic nanocomposite powders, comprising a ceramic matrix and carbon nanotubes homogeneously dispersed in the ceramic matrix. The ceramic nanocomposite powders of the invention can prevent property deterioration due to agglomeration of carbon nanotubes.

Abstract: A process for producing a carbon fiber sheet, which comprises allowing, as necessary, an oxidized polyacrylonitrile fiber sheet to contain 0.2 to 5% by mass of a resin, then subjecting the resin-containing oxidized polyacrylonitrile fiber sheet to a compression treatment in the thickness direction under the conditions of 150 to 300° C. and 5 to 100 MPa (10 to 100 MPa when no resin treatment is made) to obtain a compressed, oxidized fiber sheet having a bulk density of 0.40 to 0.80 g/cm3 and a compression ratio of 40 to 75%, and thereafter subjecting the compressed, oxidized fiber sheet to a carbonizing treatment, which carbon fiber sheet has a thickness of 0.15 to 1.0 mm, a bulk density of 0.15 to 0.45 g/cm3, a carbon fiber content of 95% by mass or more, a compression deformation ratio of 10 to 35%, an electric resistance of 6 m&OHgr; or less and a feeling of 5 to 70 g.

Abstract: A carbon fiber-carbon matrix reinforced ceramic composite comprises a carbon fiber-carbon matrix reinforcement embedded within a ceramic matrix. The ceramic matrix does not penetrate into the carbon fiber-carbon matrix reinforcement to any significant degree. The carbide matrix is a formed in situ solid carbide of at least one metal having a melting point above about 1850 degrees centigrade. At least when the composite is intended to operate between approximately 1500 and 2000 degrees centigrade for extended periods of time the solid carbide with the embedded reinforcement is formed first by reaction infiltration. Molten silicon is then diffused into the carbide. The molten silicon diffuses preferentially into the carbide matrix but not to any significant degree into the carbon-carbon reinforcement.

Abstract: Insulation materials suited to high temperature applications, such as the insulation of furnaces, are formed from a mixture of pitch carbon fibers, such as isotropic pitch carbon fibers, and a binder comprising a solution of sugar in water. The sugar solution is preferably at a concentration of from 20-60% sucrose to yield a low density material having high flexural strength and low thermal conductivity when carbonized to a temperature of about 1800° C.

Abstract: A manufacturing process for a fire component by having a mixture containing expansion graphite powder, chemical fiber and paper fiber at a specific ratio to be bound by a process normally used for the non-woven fabric, and finally hot pressed into sheet, or the mixture is treated as a pulp to be dried for serving as a fire component; accordingly, the process of the present invention gives accurate control of the mixing ratio of the expansion graphite powder and allows to increase the containment of the expansion graphite powder in the fire component up to eighty-five percent (85%), thus to significant upgrade the performance of the fire component.

Abstract: A carbon based material produced from the consolidation of amorphous carbon by elevated temperature compression. The material having unique chemical and physical characteristics that lend themselves to a broad range of applications such as in electrical, electrochemical and structural fields.

Abstract: A composite material includes a plurality of continuous graphite fiber strands, bundles, or other such fiber configurations disposed within a hardened ceramic matrix. The continuous graphite fiber strands are preferably covered or “pegged” with a ceramic slurry (e.g., a porcelain ceramic slurry), attached to a pre-formed foundation, then fired to produce a fiber-enhanced ceramic structure. In this way, a may be efficiently fabricated for use in applications requiring high-strength materials capable of withstanding temperature extremes.

Abstract: A hybrid insulation material comprises of porous ceramic substrate material impregnated with nanoporous material and method of making the same is the topic of this invention. The porous substrate material has bulk density ranging from 6 to 20 lb/ft3 and is composed of about 60 to 80 wt % silica (SiO2) 20 to 40 wt % alumina (Al2O3) fibers, and with about 0.1 to 1.0 wt % boron-containing constituent as the sintering agent. The nanoporous material has density ranging from 1.0 to 10 lb/ft3 and is either fully or partially impregnated into the substrate to block the pores, resulting in substantial reduction in conduction via radiation and convention. The nanoporous material used to impregnate the fiber substrate is preferably formed from a precursor of alkoxysilane, alcohol, water, and an acid or base catalyst for silica aerogels, and from a precursor of aluminum alkoxide, alcohol, water, and an acid or base catalyst for alumina aerogels.

Abstract: A fiberglass railcar roof that includes a fiberglass surface with a central portion and a peripheral portion adapted to be joined to the upper edge region of a railcar. In some embodiments, the roof includes plural elongate fiberglass ribs extending transverse to the longitudinal axis of the fiberglass surface. In some embodiments, the roof is adapted for use on refrigerated, high cube and cryogenic railcars. Methods for forming the invented roofs and roof panels are also disclosed.

Abstract: A multilayer ceramic composite is described which contains at least one supporting zone having oxidation-sensitive reinforcing fibers as well as a matrix. The matrix optionally contains oxidation-sensitive components. The composite further contains at least one surface layer, as well as at least one additional protective layer disposed between the supporting zone and surface layer, and whose matrix is composed substantially of at least one component of the matrix of the supporting zone or cover layer. The protective layer further contains additives that form self-healing layers.

Abstract: The invention concerns a feather-based padding product having a coherent shape resulting from the presence of a structure in the form of a three-dimensional network; said network consists of mutually bound thermoplastic fibres (2), which enclose said feathers. Said fibres (2) are first mixed with the feathers, then with appropriate heat treatment, said fibres are bonded at their contact points (5). The padding product is thus in the form of a web and it is packed in rolls or in the form of slabs.

Abstract: A powdery mixture of fine SiC powder with one or more oxide sintering additives of Al2O3, Y2O3, SiO2 and CaO is blended and uniformly dispersed in a polymeric SiC precursor to prepare a matrix-forming polymeric slurry. A preform of SiC fiber, which has quasi-stoichiometric composition with high crystallinity, is impregnated with the polymeric slurry and then hot-pressed at a temperature of 1600° C. or higher in presence of a liquid phase. Since the heat-resistant SiC fiber is used as strengthening fiber, the prepreg is sintered to a dense SiC composite excellent in mechanical properties by one-step hot-pressing.

Abstract: A method for producing ceramic matrix composites wherein the method has the steps of impregnating crystalline silicon carbide fibers coated with an interfacial coating with a ceramic matrix precursor; forming the impregnated fibers into the desired shape; curing the shape; and heating the cured shape to a temperature in the range of greater than 1450° C. to 1800° C. to convert the ceramic matrix precursor into a crystal containing ceramic. A densification step may be optionally carried out until the desired porosity/density of the ceramic matrix composite is achieved.