Abstract: This composite sintered body is a ceramic composite sintered body which includes aluminum oxide which is a main phase, and silicon carbide which is a sub-phase, the composite sintered body including an interface layer which includes, as a forming material, a material other than the aluminum oxide and the silicon carbide, at an interface between a crystal grain of the aluminum oxide and a crystal grain of the silicon carbide in a grain boundary.

Abstract: A ceramic composite can include a first ceramic phase and a second ceramic phase. The first ceramic phase can include a silicon carbide. The second phase can include a boron carbide. In an embodiment, the silicon carbide in the first ceramic phase can have a grain size in a range of 0.8 to 200 microns. The first phase, the second phase, or both can further include a carbon. In another embodiment, at least one of the first ceramic phase and the second ceramic phase can have a median minimum width of at least 5 microns.

Abstract: Provided is a SiC sintered body which contains nitrogen atoms, wherein a ratio Rmax/Rave of a maximum volume resistivity Rmax of the sintered body to an average volume resistivity Rave of the sintered body is 1.5 or lower; a ratio Rmin/Rave of a minimum volume resistivity Rmin of the sintered body to the average volume resistivity Rave is 0.7 or higher; and a relative density of the sintered body is 98% or higher.

Abstract: Disclosed is a method for providing a crystalline ceramic material. In an example, the method includes providing a silicon-containing preceramic polymer material that can be thermally converted to one or more crystalline polymorphs. The silicon-containing preceramic polymer material includes dispersed therein an effective amount of dopant particles. The silicon-containing preceramic polymer material is then thermally converted to the silicon-containing ceramic material. The effective amount of dopant particles enhance the formation of at least one of the one or more crystalline polymorphs, relative to the silicon-containing preceramic polymer without the dopant particles, with respect to at least one of formation of a selected polymorph of the one or more crystalline polymorphs formed, an amount formed of a selected polymorph of the one or more crystalline polymorphs formed, and a temperature of formation of the one or more crystalline polymorphs.

Abstract: A method for producing monolithic Zirconium Carbide (ZrC) is described. The method includes raising a pressure applied to a ZrC powder until a final pressure of greater than 40 MPa is reached; and raising a temperature of the ZrC powder until a final temperature of less than 2200° C. is reached.

Abstract: A substrate for an LED light emitting element having a small difference of linear thermal expansion coefficient with the III-V semiconductor crystal constituting an LED, having an excellent thermal conductivity, and suitable for high output LEDs. A porous body comprises one or more materials selected from silicon carbide, aluminum nitride, silicon nitride, diamond, graphite, yttrium oxide, and magnesium oxide and has a porosity that is 10 to 50 volume % and a three-point bending strength that is 50 MPa or more. The porous body is infiltrated, by means of liquid metal forging, with aluminum alloy or pure aluminum at an infiltration pressure of 30 MPa or more, cut and/or ground to a thickness of 0.05 to 0.5 mm and to a surface roughness (Ra) of 0.01 to 0.5 ?m, then is formed with a metal layer comprising one or more elements selected from Ni, Co, Pd, Cu, Ag, Au, Pt and Sn on its surface to a thickness of 0.5 to 15 ?m, so as to thereby produce the composite substrate for the LED light emitting element.

Abstract: A member for a semiconductor manufacturing apparatus includes an AlN electrostatic chuck, a cooling plate, and a cooling plate-chuck bonding layer. The cooling plate includes first to third substrates, a first metal bonding layer between the first and second substrates, a second metal bonding layer between the second and third substrates, and a refrigerant path. The first to third substrates are formed of a dense composite material containing SiC, Ti3SiC2, and TiC. The metal bonding layers are formed by thermal compression bonding of the substrates with an Al—Si—Mg metal bonding material interposed between the first and second substrates and between the second and third substrates.

Abstract: A member for a semiconductor manufacturing apparatus includes an alumina electrostatic chuck, a cooling plate, and a cooling plate-chuck bonding layer. The cooling plate includes first to third substrates, a first metal bonding layer between the first and second substrates, a second metal bonding layer between the second and third substrates, and a refrigerant path. The first to third substrates are formed of a dense composite material containing Si, SiC, and Ti. The metal bonding layers are formed by thermal compression bonding of the substrates with an Al—Si—Mg or Al—Mg metal bonding material interposed between the first and second substrates and between the second and third substrates.

Abstract: A dense composite material of the present invention contains 37% to 60% by mass of silicon carbide grains, also contains titanium silicide, titanium silicon carbide, and titanium carbide, each in an amount smaller than the mass percent of the silicon carbide grains, and has an open porosity of 1% or less. Such a dense composite material is, for example, characterized in that it has an average coefficient of linear thermal expansion at 40° C. to 570° C. of 7.2 to 8.2 ppm/K, a thermal conductivity of 75 W/mK or more, and a 4-point bending strength of 200 MPa or more.

Abstract: A dense composite material according to the present invention contains, in descending order of content, silicon carbide, titanium silicon carbide, and titanium carbide as three major constituents. The dense composite material contains 51% to 68% by mass of silicon carbide and no titanium silicide and has an open porosity of 1% or less. This dense composite material has properties such as an average linear thermal expansion coefficient of 5.4 to 6.0 ppm/K at 40° C. to 570° C., a thermal conductivity of 100 W/m·K or more, and a four-point bending strength of 300 MPa or more.

Abstract: A silicon carbide powder for the production of a silicon carbide single crystal has an average particle diameter of 100 ?m or more and 700 ?m or less and a specific surface area of 0.05 m2/g or more and 0.30 m2/g or less. A method for producing a silicon carbide powder for the production of the silicon carbide single crystal including sintering a silicon carbide powder having an average particle diameter of 20 ?m or less under pressure of 70 MPa or less at a temperature of 1900° C. or more and 2400° C. or less and in a non-oxidizing atmosphere, thereby obtaining a sintered body having a density of 1.29 g/cm3 or more; adjusting particle size by means of pulverization of the sintered body; and removing impurities by means of an acid treatment.

Abstract: Disclosed is a boron carbide-based ceramics material which has a high density and a high specific rigidity, but additionally with excellent processability, and a production method for the boron carbide-based ceramics material. Specifically, the high-rigidity ceramics material contains boron carbide in an amount of 90 to 99.5 mass %, wherein at least silicon, aluminum, oxygen and nitrogen coexist in a grain boundary phase between crystal grains of the boron carbide. This high-rigidity ceramics material can be produced by a method comprising: preparing a boron carbide powder, and, as a sintering aid, one or more selected from the group consisting of an oxide, a nitride and an oxynitride of silicon, an oxide, a nitride and an oxynitride of aluminum, and a composite oxide, a composite nitride and a composite oxynitride of aluminum and silicon, in such a manner as to contain all of Si, Al, O and N; and subjecting the boron carbide powder and the sintering aid to mixing, forming and sintering.

Abstract: A siliconized boron carbide composite material is made by infiltrating molten silicon metal into a porous mass including boron carbide. The porous mass contains little or no reactable carbon. The infiltration is designed and intended such that the infiltrant is substantially non-reactive with the constituents of the porous mass. The composite body so formed contains boron carbide and silicon metal, but substantially no silicon carbide formed in-situ from a reaction of the silicon metal with a carbon source. Such siliconized boron carbide composite materials have utility in armor applications.

Abstract: A process for the fabrication of a SiC-based article that includes preparing an aqueous suspension with SiC powder, a titanium source, a carbon source and boron carbide powder, spray drying the mixture to obtain a powder, preparing a green body from the powder, applying heat treatment to the green body in a pyrolysis/thermolysis step, pressureless sintering the green body, optimally followed by HIPing for further densification.

Abstract: A monolithic, unitary, seamless and physically continuous ceramic armor plate having first regions of one mechanical property and one chemical composition and one microstructural composition isolated from one another by a network of second regions of another mechanical property different from the one mechanical property and another chemical composition different from the one chemical composition and another microstructural composition different from the one microstructural composition, the one mechanical property and the another mechanical property being the propensity to crack.

Abstract: To obtain a ceramic fiber-reinforced composite material, by melt-infiltrating a composite material substrate obtained by forming ceramic fibers into a composite with a matrix formed of an inorganic substance, with an alloy having a composition that is constituted by a disilicate of at least one or more transition metal among transition metals that belong to Group 3A, Group 4A or Group 5A of the Periodic Table and silicon as the remainder, and having the silicon content ratio of 66.7 at % or more.

Abstract: Methods of producing continuous boron carbide fibers. The method comprises reacting a continuous carbon fiber material and a boron oxide gas within a temperature range of from approximately 1400° C. to approximately 2200° C. Continuous boron carbide fibers, continuous fibers comprising boron carbide, and articles including at least a boron carbide coating are also disclosed.

Abstract: Methods of forming composite materials include coating particles of titanium dioxide with a substance including boron (e.g., boron carbide) and a substance including carbon, and reacting the titanium dioxide with the substance including boron and the substance including carbon to form titanium diboride. The methods may be used to form ceramic composite bodies and materials, such as, for example, a ceramic composite body or material including silicon carbide and titanium diboride. Such bodies and materials may be used as armor bodies and armor materials. Such methods may include forming a green body and sintering the green body to a desirable final density. Green bodies formed in accordance with such methods may include particles comprising titanium dioxide and a coating at least partially covering exterior surfaces thereof, the coating comprising a substance including boron (e.g., boron carbide) and a substance including carbon.

Abstract: A method for producing a ceramic material product. A filler material is provided. The filler material is divided into filler granules collectively having a median diameter approximately 10 microns or less. An amount of carbon is provided. The carbon is divided into carbon particles and the carbon particles are allowed to coat the filler granules. The mixture of carbon-coated filler granules is formed into a selected shape. The formed mixture is placed in a substantial vacuum. The mixture is introduced to a pre-selected amount of silicon and the mixture of carbon-coated filler granules and silicon is heated to a temperature at or above the melting point of the silicon.

Abstract: An aspect of the present invention is to provide an economical production technology for obtaining a dense boron carbide ceramic product without impairment to excellent mechanical properties, which boron carbide ceramics are inherently equipped with, by conducting heating under normal pressure without application of pressure and without needing addition of a large amount of a sintering additive to a raw material or needing any special additive or treatment. The present invention provides a production process in which, upon heating a boron carbide green body under normal pressure without application of pressure after pressing a boron carbide powder material to obtain the boron carbide green body, the boron carbide green body is heated with one of a powder, green body or sintered body, which contains at least one of aluminum and silicon, being disposed in a furnace.

Abstract: A ceramic ballistic material and method of manufacture is disclosed. A filler material is provided. The filler material is divided into filler granules collectively having a median diameter approximately 10 microns or less. An amount of carbon is provided. The carbon is divided into carbon particles and the carbon particles are allowed to coat the filler granules. The mixture of carbon-coated filler granules is formed into a ballistic armor shape. The formed mixture is placed in a substantial vacuum. The mixture is introduced to a pre-selected amount of silicon and the mixture of carbon-coated filler granules and silicon is heated to a temperature at or above the melting point of the silicon.

Abstract: A composition for ceramic extrusion-molded bodies includes a ceramic material, a water-soluble cellulose ether, a styrenesulfonate and water. A method for manufacturing a ceramic extrusion-molded body using the composition is also provided.

Abstract: This invention provides carbon composite materials, which comprise metal carbide particles, at least the particle surfaces or the entirety of which are metal carbides, synthesized in situ from a metal source, i.e., at least one member selected from the group comprising metal particles, metal oxide particles, and composite metal oxide particles, and a carbon source, i.e., a thermosetting resin, dispersed in a carbon, carbon fiber, or carbon/carbon fiber matrix, and contain no free metal particles. This invention also provides a method for producing such composite carbon materials, which enables the production of carbon composite materials having a high coefficient of friction, high thermostability, and abrasion resistance.

Abstract: A reaction sintered silicon carbide-based product, including a silicon carbide component, a bond component, wherein the bond component includes silicon oxynitride in excess of any silicon nitride of the bond component, and at least one boron component residual to an amount present prior to reaction sintering to cause increased resistance of the reaction sintered silicon carbide-based product to volume change under oxidative stress, and methods of making the same.

Abstract: A dense silicon carbide (SiC) material with boron (B), nitrogen (N) and oxygen (O) as the only additives and with excellent insulting performance (electrical volume resistivity greater than 1×108 ?·cm). The SiC ceramic material, made from a powder mix of, by weight, from 0.1 to 7% boron carbide, from 0.1 to 7% silicon nitride, from 0.1 to 6% silicon dioxide, and a balance of ?-SiC, consists essentially of (1) at least 90% by weight of ?-SiC, (2) about 0.3 to 4.0% by weight of boron, (3) about 0.1 to 6.0% by weight of nitrogen, (4) about 0.06 to 0.5% by weight of oxygen, and (5) no more than 0.07% by weight of metallic impurities; wherein the boron and nitrogen are present according to an B/N atomic ratio of 0.9 to 1.5. In particular, this material is suitable for applications in plasma etching chambers for semiconductor and integrated circuit manufacturing.

Abstract: A method of forming a sintered silicon carbide body includes mixing silicon carbide powder having an oxygen content of less than about 3 wt % and having a surface area in a range of between about 8 m2/g and about 15 m2/g, with boron carbide powder and carbon sintering aid to form a green silicon carbide body. Alternatively, a method of producing a sintered silicon carbide body includes mixing the silicon carbide powder with titanium carbide powder having an average particle diameter in a range of between about 5 nm and about 100 nm and with carbon sintering aid to form a green silicon carbide body. In another alternative, a method of forming a sintered silicon carbide body includes mixing silicon carbide powder with boron carbide powder, the titanium carbide powder, and carbon sintering aid to form a green silicon carbide body. After sintering, the silicon carbide bodies have a density at least 98% of the theoretical density of silicon carbide.

Abstract: Disclosed herein is a component in a combustion system comprising a composite, the composite comprising silicon carbide; and a refractory metal silicide comprising a phase selected from Rm5Si3, Rm5Si3C, RmSi2, and a combination thereof; wherein Rm is a refractory metal selected from molybdenum, tungsten, and a combination thereof. Also disclosed is a process for preventing slag, ash, and char buildup on a surface, comprising disposing a first surface of the composite on the surface; replacing a component comprising the surface with a component consisting of the composite; or a combination thereof.

Abstract: Disclosed herein is a component in a combustion system comprising a composite, the composite comprising silicon carbide; and a refractory metal silicide comprising a phase selected from Rm5Si3, Rm5Si3C, RmSi2, and a combination thereof; wherein Rm is a refractory metal selected from molybdenum, tungsten, and a combination thereof. Also disclosed is a process for preventing slag, ash, and char buildup on a surface, comprising disposing a first surface of the composite on the surface; replacing a component comprising the surface with a component consisting of the composite; or a combination thereof.

Abstract: A reaction bonded ceramic body that has 50% to 60%, by weight, boron carbide, and 20% to 30%, by weight, silicon carbide. The reaction bonded ceramic body has least a portion of the boron carbide reacted with silicon to become siliconized boron carbide. Also, a method of making a reaction bonded ceramic material. The method may include the steps of forming a green body from a mixture of boron carbide, carbon, and an organic binder, and contacting the green body with a liquid infiltrant comprising silicon. The infiltrant has a temperature of about 1625° C. to about 1700° C. Furthermore, a method of making a reaction bonded boron carbide ceramic body. The method includes the steps of forming a green body from a mixture of boron carbide, carbon, and an organic binder. The weight ratio of boron carbide to carbon in the green body may be about 5:5 to 1 or more.

Abstract: A composite material according to the invention includes X parts by volume of boron carbide, Y parts by volume of silicon carbide, and Z parts by volume of silicon as main components, wherein 10<X<60, 20<Y<70, and 5<Z<30 are satisfied, and grains of 10 ?m or more of the boron carbide and the silicon carbide are 10-50 parts by volume.

Abstract: The present invention contemplates the addition of zirconium compounds to well known ceramic ballistic materials to increase resistance to penetration by projectiles. In the preferred embodiments of the present invention, the zirconium compound that is employed consists of ZrO2 and is provided in the range of about 0.1% to about 11%, by weight, of starting material before densification. Preferred ranges of proportion of ZrO2 in the finished ceramic material are in the ranges of about 0.30% to about 0.75%, by weight, or about 8-9%, by weight. The ballistic material using the combination of SiC with low volume of sintering aid and ZrO2 raises the theoretical density of the ceramic material to between 3.225 and 3.40 g/cc, which is slightly higher than the typical 3.22 g/cc theoretical density for hot pressed fully dense SiC.

Abstract: The present invention contemplates the addition of zirconium compounds to well known ceramic ballistic materials to increase resistance to penetration by projectiles. In the preferred embodiments of the present invention, the zirconium compound that is employed consists of ZrO2 and is provided in the range of about 0.1% to about 11%, by weight, of starting material before densification. Preferred ranges of proportion of ZrO2 in the finished ceramic material are in the ranges of about 0.30% to about 0.75%, by weight, or about 8-9%, by weight. The ballistic material using the combination of SiC with low volume of sintering aid and ZrO2 raises the theoretical density of the ceramic material to between 3.225 and 3.40 g/cc, which is slightly higher than the typical 3.22 g/cc theoretical density for hot pressed fully dense SiC.

Abstract: A boron carbide sintered body having a plurality of pores, comprises a boron carbide as a main component and a plurality of graphite particles dispersed in the sinter. The graphite particles is exposed to the pores or is in the vicinity of the pores.

Abstract: A dense silicon carbide (SiC) material with boron (B), nitrogen (N) and oxygen (O) as the only additives and with excellent insulting performance (electrical volume resistivity greater than 1×108 ?.cm). The SiC ceramic material, made from a powder mix of, by weight, from 0.1 to 7% boron carbide, from 0.1 to 7% silicon nitride, from 0.1 to 6% silicon dioxide, and a balance of ?-SiC, consists essentially of (1) at least 90% by weight of ?-SiC, (2) about 0.3 to 4.0% by weight of boron, (3) about 0.1 to 6.0% by weight of nitrogen, (4) about 0.06 to 0.5% by weight of oxygen, and (5) no more than 0.07% by weight of metallic impurities; wherein the boron and nitrogen are present according to an B/N atomic ratio of 0.9:1 to 5:1. In particular, this material is suitable for applications in plasma etching chambers for semiconductor and integrated circuit manufacturing.

Abstract: A batch mixture including ceramic-forming ingredients, a pore former, a binder comprising an ammonium salt of an alkylated cellulose binder, and a liquid vehicle, as defined herein. Also disclosed is a method for producing a ceramic precursor article as defined herein having excellent extrusion properties.

Abstract: A heating apparatus comprising an energetic nanolaminate film that produces heat when initiated, a power source that provides an electric current, and a control that initiates the energetic nanolaminate film by directing the electric current to the energetic nanolaminate film and joule heating the energetic nanolaminate film to an initiation temperature. Also a method of heating comprising providing an energetic nanolaminate film that produces heat when initiated, and initiating the energetic nanolaminate film by directing an electric current to the energetic nanolaminate film and joule heating the energetic nanolaminate film to an initiation temperature.

Abstract: A porous refractory product includes a matrix of sintered silicon carbide having a porosity of about 45% to about 65%. The matrix is formed by heating in a noble gas atmosphere a cast preform including a mixture of alpha-silicon carbide and boron carbide each having a particle size of less than about 1 micron. The heating causes the formation of gaseous SiO within the silicon carbide matrix, which, in turn, forms pores having an average size of less than about 1 micron. The porous refractory products herein are suitable for use in a variety of applications including for use in high temperature particulate filtering applications.

Abstract: This chemical vapor synthesis process was designed so that a metal carbide precursor and a secondary metal precursor are separately or together fed into each evaporator in a reactor by specially designed precursor feeders, either simultaneously or sequentially. The reduction and carburization of the vaporized precursors by gaseous mixtures produces carbide-metal nanocomposite powders. The product can be a very uniform mixture of the constituent powders or a uniform agglomerate, which is important to ensure a high quality of bulk cemented metal carbide product after consolidation and sintering. These nanocomposite powders can be readily characterized using XRD, carbon analyzer and TEM.

Abstract: The invention relates to a process for the production of a molded porous ceramic article containing ?-SiC, which process comprises the following steps: the preparation of a molded article containing silicon and carbon and the subsequent pyrolysis and siliconization of the article containing silicon and carbon to form SiC. The invention further relates to a molded porous ceramic article containing SiC which has been produced from a molded article containing silicon and carbon.

Abstract: A reaction sintered silicon carbide-based product, including a silicon carbide component, a bond component, wherein the bond component includes silicon oxynitride in excess of any silicon nitride of the bond component, and at least one boron component residual to an amount present prior to reaction sintering to cause increased resistance of the reaction sintered silicon carbide-based product to volume change under oxidative stress, and methods of making the same.

Abstract: A composite material according to the invention includes X parts by volume of boron carbide, Y parts by volume of silicon carbide, and Z parts by volume of silicon as main components, wherein 10<X<60, 20<Y<70, and 5<Z<30 are satisfied, and grains of 10 ?m or more of the boron carbide and the silicon carbide are 10-50 parts by volume.

Abstract: A precursor of a ceramic adhesive suitable for use in a vacuum, thermal, and microgravity environment. The precursor of the ceramic adhesive includes a silicon-based, preceramic polymer and at least one ceramic powder selected from the group consisting of aluminum oxide, aluminum nitride, boron carbide, boron oxide, boron nitride, hafnium boride, hafnium carbide, hafnium oxide, lithium aluminate, molybdenum silicide, niobium carbide, niobium nitride, silicon boride, silicon carbide, silicon oxide, silicon nitride, tin oxide, tantalum boride, tantalum carbide, tantalum oxide, tantalum nitride, titanium boride, titanium carbide, titanium oxide, titanium nitride, yttrium oxide, zirconium, diboride, zirconium carbide, zirconium oxide, and zirconium silicate. Methods of forming the ceramic adhesive and of repairing a substrate in a vacuum and microgravity environment are also disclosed, as is a substrate repaired with the ceramic adhesive.

Abstract: The compressive strength of a boron carbide sintered compact is improved by controlling crystals of the boron carbide to a polycrystalline structure having a grain size distribution in which coarse crystals with a grain size of 20 ?m or more and fine crystals with a grain size of 10 ?m or less are mixed in an appropriate ratio. Furthermore, a protective member having an improved compressive strength can be provided using the boron carbide sintered compact having a polycrystalline structure in which coarse crystals and fine crystals are mixed in an appropriate ratio or a boron carbide sintered compact containing graphite and silicon carbide.

Abstract: A composite body produced by a reactive infiltration process that possesses high mechanical strength, high hardness and high stiffness has applications in such diverse industries as precision equipment and ballistic armor. Specifically, the composite material features a boron carbide filler or reinforcement phase, and a silicon component with a porous mass having a carbonaceous component. Potential deleterious reaction of the boron carbide with silicon during infiltration is suppressed by alloying or dissolving boron into the silicon prior to contact of the silicon infiltrant with the boron carbide. In a preferred embodiment of the invention related specifically to armor, good ballistic performance can be advanced by loading the porous mass or preform to be infiltrated to a high degree with one or more hard fillers such as boron carbide, and by limiting the size of the largest particles making up the mass.

Abstract: A slip-cast article former containing ternary ceramics, particularly of carbide and nitride materials, having the formula Mn+1AXn(MAX), where M is a transition metal, A is an element from Groups IA and IVA of the periodic table, X is nitrogen or carbon and n is 1, 2, or 3. The ternary ceramic article may be a glove or condom former. A process for making a ternary ceramic article employing a slip cast method.

Abstract: Ceramic igniter compositions are provided that contain components of conductive material and insulating material, where the insulating material component includes a relatively high concentration of metal oxide. Ceramic igniters of the invention are particularly effective for high voltage use, including throughout the range of from about 187 to 264 volts.

Abstract: A slip-casted article former containing ternary ceramics, particularly of carbide and nitride materials, having the formula M.sub.n+1AX.sub.n (MAX), where M is a transition metal, A is an element from Groups IIIA and IVA of the periodic table, X is nitrogen or carbon and n is 1, 2, or 3. The ternary ceramic article may be a glove or condom former. A process for making a ternary ceramic article employing a slip cast method.

Abstract: Composite materials containing silicon, titanium, carbon, and nitrogen, formed by spark plasma sintering of ceramic starting materials to a high relative density, demonstrate unusually high electrical conductivity as well as high-performance mechanical and chemical properties including hardness, fracture toughness, and corrosion resistance. This combination of electrical, mechanical, and chemical properties makes these composites useful as electrical conductors in applications where high-performance materials are needed due to exposure to extreme conditions such as high temperatures, mechanical stresses, and corrosive environments.

Abstract: Layered metal non-oxide coated substrates are disclosed comprising a three dimensional inorganic substrate having a coating of metal non-oxide derived from a pre-associated coating on at least a portion of all three dimensions thereof, produced by a unique process having particular applicability to the manufacture of metal boride, carbide and nitride coated three dimensional substrates. Certain novel coated substrates, such as flakes, spheres and porous substrate are disclosed. The coated substrates are useful in polymer catalysis, heating and shielding applications.

Abstract: A silicon-containing composite body that would otherwise be brittle can be engineered to exhibit enhanced fracture toughness. Specifically, a silicon-ceramic composite body is produced, preferably by a reactive infiltration technique. The ceramic is selected such that it has a higher coefficient of thermal expansion (CTE) than does the silicon phase. At least at some point during processing, the silicon phase is at a temperature above its normal ductile/brittle transition temperature of about 500° C., and preferably above its melting point. The formed composite body containing the silicon phase is then cooled below its ductile/brittle transition. During cooling, the ceramic phase shrinks more than does the silicon phase, thereby placing the latter in a state of compressive stress. By the time the composite body has cooled to substantially ambient temperature, the induced compressive stress in the silicon phase is sufficient as to impart a measurable degree of semi-ductile character to the silicon phase.