Abstract: A substance for increasing friction between two surfaces such as two metallic surfaces has a gel base material determining the viscosity of the substance and contains hard crystals mixed into the gel based material. A plurality of the hard crystals is comprised of a first particles of the first substantially identical particle size and second particles of the second substantially identical particle size. The first and second particle sizes have a fixed ratio relative to one another.

Abstract: Disclosed herein is a process for the preparation of alkylsilanes and alkenyl silanes by hydrosilylation of their corresponding silanes and unsaturated hydrocarbons in the presence or absence of a catalyst, a process for the preparation of polyalkenylsilanes (some of which are high molecular compounds) by the anionic coordination polymerization, radical polymerization or ionic polymerization of the alkenylsilanes, and a process for the production of silicon carbide by using these polyalkenylsilanes as prepolymers.

Abstract: A silicon carbide material in the form of fibers, sheets or three-dimensionally structured articles useful as a reinforcing material and heat-insulating material, is produced by reacting an activated porous carbon material in the form of, for example, fibers, sheets or three-dimensionally structured articles, and having a specific surface area of 100 to 2500 m.sup.2 /g, with silicon monoxide gas at a temperature of 800.degree. C. to 2000.degree. C. and then heat-treating the resultant silicon carbide material in a non-oxidative gas atmosphere containing nitrogen and substantially no oxygen at a temperature of 800.degree. C. to 2000.degree. C.

Abstract: A process for producing oxygen-free or low-oxygen shaped bodies of silicon carbide, particularly SiC fibers, by using chemically reactive polysilanes and/or polycarbosilanes as precursors. In accordance with the invention green fibers are stabilized preferably in the presence of reactive gases.

Abstract: A substrate for use in semiconductor devices, fabricated of silicon carbide and having a resistivity of greater than 1500 Ohm-cm. The substrate being characterized as having deep level impurities incorporated therein, wherein the deep level elemental impurity comprises one of a selected heavy metal, hydrogen, chlorine and fluorine. The selected heavy metal being a metal found in periodic groups IIIB, IVB, VB, VIB, VIIB, VIIIB, IB and IIB.

Abstract: A processable blend having high temperature and thermal shock resistance properties includes a resin blend which includes at least one first silicone polymer and at least one second silicone polymer. The processable blend is ceramitizable at a temperature above about 1100.degree. F. A method of producing an article with high temperature and thermal shock resistance properties includes forming a silicone blend of at least one first silicone polymer and at least one second silicone polymer, wherein the blend is ceramitizable at a temperature above about 1100.degree. F.; forming the blend into the shape of the desired article; and, at least partially curing at least one of said silicone polymers at a temperature below the ceramitization temperature.

Abstract: Mechanically strong and reduced friction porous silicon carbide sintered shaped articles, well adapted for the production, e.g., of leaktight mechanical packings and rotating bearing seals, have a total pore volume ranging from 4% to 18% thereof, the pores of which having an average diameter ranging from 40 to 200 .mu.m.

Abstract: A superplastic silicon carbide sintered body which comprises at least 85 wt % and at most 98 wt % of silicon carbide grains and more than 2 wt % and less than 15 wt % of a grain boundary phase and which has a relative density of at least 95%, wherein the silicon carbide grains have an average grain size of at most 0.3 .mu.m, the amount of grains having grain sizes exceeding 0.5 .mu.m is at most 3 wt %, and the deformation rate of the sintered body is at least 10.sup.-4 /sec under a compression or tensile stress of from 50 to 2,000 kg/cm.sup.2 within a temperature range of from 1,600.degree. to 1,800.degree. C.

Abstract: A porous membrane produced by preparing a slurry made from at least one micropyretic substance and at least one liquid carrier. The slurry is dried into a green form having a desired geometric configuration. Combustion of the green form produces the porous membrane.

Abstract: A process for the preparation of a silicon carbide sintered body of high purity which has a content of 1 ppm or less of each atom harmful to the manufacture of semiconductor equipment including the step of shaping a silicon carbide powder, calcining the shaped body in a non-oxidizing atmosphere to form a porous body, and subjecting the porous body to reaction sintering while being impregnated with molten metallic silicon. The starting silicon carbide powder also has a content of 1 ppm or less of each harmful atom and it has a free carbon content of not greater than 20% by weight and an average particle diameter of 0.5-20 .mu.m.

Abstract: Silicon carbide sintered bodies having controlled porosity in the range of about 2 to 12 vol %. in which the pores are generally spherical and about 50 to 500 microns in diameter, are prepared from raw batches containing a polymer fugitive. Sintered bodies in the form of mechanical seal members exhibit lower power consumption at low PV and, in addition, lower wear rates at high PV in comparison to commercially available silicon carbide seal members.

Abstract: A self-sintered silicon carbide/carbon-graphite composite material having interconnected pores which may be impregnated, and a raw batch and process for producing the composite material, is provided. The composite material comprises a densified, self-sintered matrix of silicon carbide, carbon-graphite inclusions and small amounts of any residual sintering aids, such as boron and free carbon, and has interconnected pores which may be impregnated with resin, carbon, TEFLON, metal or other compounds or materials selected for their particular properties to achieve desired tribological characteristics for a specific application. The composite material is produced from a raw batch which includes silicon carbide, sintering aids, a temporary filler and coated graphite particles. The raw batch is then molded/shaped into a green body and heated to carbonize any carbonizable materials and to decompose and volatilize the organic filler to form a matrix of interconnected pores.

Abstract: A method of forming a highly dispersed ceramic powder slurry is provided prising forming an aqueous based slurry of a ceramic powder and a polyelectrolyte at an acidic pH and adjusting the pH of the slurry to an alkaline value.

Abstract: Strengthened and toughened ceramic composite bodies are achieved through the use of a silicon boride composition of silicon borides and borides of the form Si-B-C. This strengthening and hardening is achieved when the silicon boride composition is present over a wide range, although a preferred amount is about 20 wt. %. This strengthening and toughening occurs for oxides, carbides, nitrides, and mixtures thereof, for example. One silicon boride composition for this application is silicon hexaboride. Further enhancement is achieved by the addition of up to about 25 wt. % carbon in the silicon hexaboride. Accordingly, the preferred silicon boride composition is a Si-B-C composition, with carbon being added to SiB.sub.6, for example.

Abstract: A founder's black for producing mould coatings is disclosed, whose main component consists of finely ground refractory to highly refractory inorganic materials. The black wash contains 1 to 40% by weight inorganic hollow spheres, in relation to the ready-to-use black wash. It may further contain 0.1 to 10% by weight of inorganic or organic fibers, in relation to the ready-to-use mould coating. The hollow spheres are preferably filled with an inert gas. They may consist of oxides such as aluminium oxide, quartz, magnesite, mullite, chromite, zircon oxide and/or titanium oxide, or borides, carbides and nitride such as silicium carbide, titanium carbide, or carbon, glass or metals, or mixtures thereof. The fibres have 1 to 30 .mu.m diameter, preferably 3 to 10 .mu.m and 10 to 5000 .mu.m length, preferably 100 to 500 .mu.m length.

Abstract: The present invention provides for microporous ceramic materials having a surface area in excess of 50 m.sup.2 /gm and an open microporous cell structure wherein the micropores have a mean width of less than 20 Angstroms and wherein said microporous structure comprises a volume of greater than about 0.015 cm.sup.3 /gm of the ceramic. The invention also provides for a preceramic composite intermediate composition comprising a mixture of a ceramic precursor and finely divided particles comprising a non-silicon containing ceramic, carbon, or an inorganic compound having a decomposition temperature in excess of 400.degree. C., whose pyrolysis product in inert atmosphere or in an ammonia atmosphere at temperatures of up to less than about 1100.degree. C. gives rise to the microporous ceramics of the invention.

Abstract: The present invention is directed to compositions derived from polymers containing metal-nitrogen bonds, which compositions exhibit, among other things, desirable oxidation resistance, corrosion resistance and hydrolytic stability when exposed to adverse environments, whether at ambient or at elevated temperatures, and which may be useful as, for example, protective coatings on surfaces.

Abstract: The subject-matter of the present invention is to solve the technical problem resulting from the instability in air of polysilanes. For this purpose, it proposes a polysilane-based composition, used particularly for producing silicon carbide, comprising:polysilane chains capable of being degraded by oxidation and the formation of polysiloxane-type products and/or polysilane chains suitable for being bound together directly by a reaction between Si--H and Si--X radicals, and/or indirectly through the intermediary of a crosslinking additive and by a reaction between A--X and A--H radicals, X being an olefin radical, preferably comprising 1 to 18 carbon atoms and, more preferably still, being constituted by a vinyl radical (Vi:--CH.dbd.CH.sub.2), A being an organic, organosilicic or silicic radical;and at least one antioxidant system.

Abstract: A processable blend having high temperature and thermal shock resistance properties includes a resin blend which includes at least one first silicone polymer and at least one second silicone polymer. The processable blend is ceramitizable at a temperature above about 1100.degree. F. A method of producing an article with high temperature and thermal shock resistance properties includes forming a silicone blend of at least one first silicone polymer and at least one second silicone polymer, wherein the blend is ceramitizable at a temperature above about 1100.degree. F.; forming the blend into the shape of the desired article; and, at least partially curing at least one of said silicone polymers at a temperature below the ceramitization temperature.

Abstract: A composite is comprised of reinforcement fibers having a continuous coating with a first layer of a metal oxide wherein the metal is from the group consisting of aluminum, yttrium, titanium, zirconium, beryllium, silicon, and the rare earths, and a molten silicon infiltration formed silicon carbide matrix. The coating may have a second layer from the group consisting of rhodium, iridium, metal carbide, metal silicide, metal nitride, and metal diboride, on the metal oxide coating. The reinforcement fibers being fibers from the group consisting of elemental carbon, silicon carbide, and mixtures thereof. A process for producing the fiber reinforced composite comprises depositing on the fibers a continuous coating comprised of the first layer of the metal oxide, and the second layer. A carbonaceous material is admixed with the coated fibers so that at least 5 volume percent of the mixture is the fibers.

Abstract: A block copolymer is prepared by reacting an aluminum-nitrogen polymer and a silazane polymer at a temperature not greater than 400.degree. C. Block copolymers containing alkenyl or alkynyl groups can be crosslinked by supplying energy to generate free radicals. An AlN/SiC-containing ceramic is formed by pyrolyzing the crosslinked block copolymer in a nonoxidizing atmosphere.

Abstract: This invention relates to a composite of silicon carbide and carbon. This invention also relates to its manufacturing method. An obtained composite is used as heat resistant, wear resistant or chemical resistant materials. The object of this manufacturing method is to form a deep layer of silicon carbide and carbon in the surface of a carbon base by a simple process of causing a silicon containing material to penetrate into and react with the carbon block. Further object of this invention is to produce a compound in whole comprised of silicon carbide and carbon if the carbon block is 20 mm or below in thickness. To this end, according to this forming method a carbon block having a lattice constant c of 6.708 .ANG. to 6.900 .ANG. or below and a density of 1.3 g/cm.sup.3 to 1.7 g/cm.sup.

Abstract: A plastic material composed of silicon carbide powder, polycarbosilane, organic solvent, and optionally boron compounds and/or other additives, preferably porosity agents; and the use of this plastic composition for producing shaped parts and semi-finished products by plastic shaping.

Abstract: A zirconia based composite material with improved strength and toughness includes a partially stabilized zirconia including 1.5 to 4.5 mol % of yttrium oxide as a matrix thereof and a metal phase of at least one metal selected from the group consisting of titanium, vanadium, niobium, tantalum, chromium, molybdenum and tungsten as metal grains dispersed in the matrix. The metal phase has a melting point higher than a sintering temperature of the partially stabilized zirconia. In addition, it is preferred that the composite material further contains a ceramic phase of at least one ceramic selected from the group consisting of Al.sub.2 O.sub.3, SiC, Si.sub.3 N.sub.4, B.sub.4 C, carbides, nitrides and borides of titanium, vanadium, niobium, tantalum, chromium, molybdenum and tungsten as ceramic grains dispersed in the matrix. The composite material of the present invention is manufactured by the following steps.

Abstract: In accordance with the invention, a composition of matter is provided for forming a coating for protecting carbonaceous substrates from degradation at elevated temperatures. The composition is a mixture of particulate silicon, silicon carbide and boron. The mixture contains between about 25% and 40% silicon by weight of the total composition, between about 50% and 70% by weight silicon carbide by weight of the total composition, between about 1% and 15% boron by way of the total composition and a minor amount of magnesium. The compositions can be used in a method for forming a primary protective coating on carbonaceous substrates including, in particular, reinforced carbon-carbon materials produced using chemical vapor deposition techniques.

Abstract: Process for the production of a carbon/carbon composite material using mesophase powder.The process according to the invention comprises the stages of dispersing infusible mesophase microspheres in a solution containing a binder and a solvent able to wet the carbon fibres and thus form an impregnation bath (20), the binder and the solvent not being carbon precursors, impregnating each fibre (1) by the bath, placing (24) the impregnated fibres in a mould and unidirectionally pressing or compressing (26) the impregnated fibres in the mould whilst heating them to a first temperature T.sub.1 above ambient temperature suitable for evaporating the solvent and the binder and making the mesophase microspheres flow to a second temperature T.sub.2 above the first temperate and suitable for pyrolyzing the mesophase microspheres in coke form.

Abstract: A ceramic adhesive comprises a ceramic matrix formed from a mixture of a metallic oxide and an alkali silicate in water, the ceramic matrix further having a sealed porosity, and silicon carbide whiskers dispersed within the ceramic matrix. Further, a ceramic adhesive comprises a ceramic matrix formed from a mixture of magnesium oxide in the range of about 50% to about 80% by weight and sodium silicate in water in the range of about 50% to about 20% by weight, and silicon carbide whiskers dispersed within said ceramic matrix, the whiskers being in the range of about 3% to about 25% by weight of the ceramic matrix. The porosity of the ceramic adhesive is sealed by an organic epoxy resin. A ceramic adhesive of the present invention is particularly useful in mounting and bonding in-cylinder sensors to steel internal engine parts.

Abstract: Metal and/or metalloid nitride and/or carbide powders, e.g., amorphous or crystalline spherical particulates having a mean diameter greater than 0.2 .mu.m 90% of which being less than 0.4 .mu.m in size, well suited for the production of ceramic shaped articles exhibiting good thermomechanical properties and useful, for example, in the automotive and aeronautic fields, are prepared by flash pyrolyzing coarse drops of a precursor compound convertible into such nitride and/or carbide, at an elevated temperature and for such period of time as to convert the precursor compound into said amorphous or crystalline powder.

Abstract: Electrically conductive sputtering target comprising yttria and amorphous carbon, a method of making the same, and a method of using the same.

Abstract: This invention is directed to a process for forming noninterwoven dispersed particulate composite products. In one case a composite multi-layer film product comprises a substantially noninterwoven multi-layer film having a plurality of discrete layers. This noninterwoven film comprises at least one discrete layer of a first material and at least one discrete layer of a second material. In another case the first and second materials are blended together with each other. In either case, the first material comprises a metalloid and the second material a metal compound. At least one component of a first material in one discrete layer undergoes a solid state displacement reaction with at least one component of a second material thereby producing the requisite noninterwoven composite film product. Preferably, the first material comprises silicon, the second material comprises Mo.sub.2 C, the third material comprises SiC and the fourth material comprises MoSi.sub.2.

Abstract: The strength of a composite sintered body including yttrium oxide is improved. A composite ceramics sintered body includes a matrix of yttrium oxide and silicon carbide particles dispersed within the matrix. A compound oxide phase including yttrium and silicon is present at the surface of the sintered body. A sintered body is obtained by compression-molding mixed powder including yttrium oxide powder and silicon carbide powder in an inert gas atmosphere of at least 1550.degree. C. The sintered body is subjected to a heat treatment for at least 0.5 hour and not more than 12 hours in an atmosphere including oxygen gas in the range of at least 900.degree. C. and less than 1200.degree. C.

Abstract: An adhesive composition for joining carbon--carbon composites comprising a polymeric thermosetting polysilazane, a ceramic powder, silicon powder, and carbon powder. The invention also comprises the method of making carbon--carbon composite structures utilizing such adhesive composition and to the resultant products.

Abstract: The present invention provides linear organosilicon polymers including acetylene and vinylene moieties, and a process for their preparation. These diorganosilacetylene-alt-diorganosilvinylene linear polymers can be represented by the formula: --[--(R.sup.1)(R.sup.2)Si--C.tbd.C--(R.sup.3)(R.sup.4)Si--CH.dbd.CH--].sub .n --, wherein n.gtoreq.2; and each R.sup.1, R.sup.2, R.sup.3, and R.sup.4 is independently selected from the group consisting of hydrogen, halogen, alkyl, alkenyl, aryl, and aralkyl radicals. The polymers are soluble in organic solvents, air stable, and can be pulled into fibers or cast into films. They can be thermally converted into silicon carbide ceramic materials.

Abstract: Carbon-containing black glass compositions of matter having the empirical formula SiC.sub.x O.sub.

Abstract: The invention concerns a process for preparing a silicon carbide foam consisting of attacking a polyurethane foam with an alkaline solution, impregnating it, after rinsing and drying, with a suspension of silicon powder in an organic resin, heating progressively to polymerise the resin, carbonising the polyurethane foam and resin, and finally carburising the silicon contained in the resin suspension by means of the carbon originating from the carbonisation of the foam and resin.The foams obtained are characterised by a high microporosity and a mesoporosity which is variable according to the carburising temperature.The invention finds an application in the manufacture of catalyst carriers for exhaust chambers and filters for diesel engines.

Abstract: Silicon carbide sintered bodies having controlled porosity in the range of about 3-25 vol % are prepared from raw batches containing a multimodal distribution of silicon carbide particles and comprised of at least a first set of particles having one average grain size and a second set of particles having another average grain size larger than the first set of particles. The resulting pores are 3-5 microns in the largest dimension, with an aspect ratio between about 1/1 and about 3/1 . The porous bodies, e.g., in the form of mechanical seal members, exhibit good tribological properties.

Abstract: Disclosed is a process for the formation of silicon carbide powder in which vaporized polysiloxanes are reacted and pyrolyzed in a single heating step to form the silicon carbide powder. The process is simple and inexpensive and yields powder having desirable characteristics.

Abstract: This invention broadly relates to methods for producing self-supporting silicon carbide and silicon carbide composite bodies. More particularly, this invention relates to silicon carbide and silicon carbide composites, grown by the oxidation reaction of a silicon metal with a gas comprising at least one gas selected from the group consisting of fluorinated hydrocarbon gases, chlorohydrocarbon gases, and chlorofluorocarbon gases.

Abstract: A process for preparing a silicon carbide foam by impregnating a polyurethane foam with a suspension of silicon powder in an organic resin, heating progressively to polymerize the resin, heating further to carbonize the polyurethane foam and resin, and finally further heating to carburize the silicon contained in the resin suspension by means of carbon obtained from the carbonization of the foam and resin. The foam obtained is characterized by high macroporosity and a mesoporosity which is variable according to the carburizing temperature.

Abstract: A dense, self-sintered silicon carbide/carbon-graphite composite material and a process for producing the composite material is disclosed. The composite material comprises a silicon carbide matrix, between 2 and 30 percent by weight carbon-graphite, and small amounts of sintering aids such as boron and free carbon. The silicon carbide has an average grain size between 2 and 15 .mu.m, and the carbon-graphite has an average grain size between 10 and 75 .mu.m, the average grain size of the carbon-graphite being greater than the average grain size of the silicon carbide. The composite material has a density of at least 80 percent of theoretical density as determined by the rule of mixtures for a composite material. This density is achieved with minimal microcracking at a high graphite loading with large graphite particles. The composite material exhibits good lubricity and wear characteristics, resulting in improved tribological performance.

Abstract: The present invention discloses a composition for a valve of an advanced heat engine. The valve comprises grains of aluminum-doped silicon carbide. The grains are of two main types: (1) a matrix of equi-axed grains of alpha and beta SiC for optimum distribution of mechanical properties; and (2) elongated grains of alpha SiC which are distributed within the matrix for reinforcement. The invention also comprises a process for making such valves. The process begins with a powder of aluminum-doped beta-silicon carbide. A binder and a solvent are then added to the powder, and the mixture is agitated while being heated. The mixture is then transferred to an injection mold which is used to form a molded component. The molded component is then sintered and machined into desired dimensions. An annealing step is then performed so that the component exhibits the characteristics of improved strength and toughness.

Abstract: A method of processing water-sensitive ceramic powders, particularly carbothermically produced aluminum nitride, whereby the ceramic powder is deagglomerated in a dry milling step with addition of an alkylamine which is liquid at room temperature is disclosed. The alkylamine is added in an amount sufficient to produce a monomolecular layer on the surface of the ceramic powder. The deagglomerated powder subsequently is vigorously stirred with a concentrated aqueous solution or dispersion of binder and rapidly and gently dried, preferably by freeze drying. Aluminum nitride powder prepared by this process can be further processed into shaped parts with a high thermal conductivity.

Abstract: Silicon carbide sintered bodies having controlled porosity in the range of about 2 to 12 vol %. in which the pores are generally spherical and about 50 to 500 microns in diameter, are prepared from raw batches containing a polymer fugitive. Sintered bodies in the form of mechanical seal members exhibit lower power consumption at low PV and, in addition, lower wear rates at high PV in comparison to commercially available silicon carbide seal members.

Abstract: The invention relates to fine non-oxide ceramic powders MeX, whereinMe=B, Al, Si, Ti, Zr, Hf, V, Y, Ta, Nb, Mo, W, La, Fe, Co, Ni and/or Cr andX=C, N, B and Si or combinations thereof, with the exception of Si.sub.3 N.sub.4 greater than 100 nm and AlN greater than 200 nm.

Abstract: The apparatus for regulating liquid specimen temperature is used to maintain the liquid temperature of a sample constant in order to maintain a specific reaction state of the sample in an apparatus for analyzing samples, such as a blood analyzing apparatus. In this apparatus, a main body is included which is made of ceramics comprised mainly of silicon carbide high in thermal efficiency and excellent in chemical resistance. A liquid inlet is disposed at one end of a passage passing through the main body, which is used for heating. Preferably, the liquid inlet is opened toward the passage inner wall, and a liquid separating member for moving the liquid as it flows into the passage is disposed in the passage. When the liquid separating member is installed in the passage, the incoming liquid, not controlled in temperature, and the liquid leaving the passage already controlled in temperature may be separated, so that liquid control precision may be enhanced.

Abstract: There are disclosed a process for producing a uniformly mixed composite raw material for ceramics by recovering the uniformly mixed composite raw material for ceramics from the dispersion of at least two types of raw materials for ceramics and optionally a component other than said materials in a liquid medium, which comprises coagulating and precipitating the composite raw material together with aluminum hydroxide formed by reacting an aluminum salt with an alkali in the liquid medium; and a uniformly mixed composite raw material for ceramics which is produced by the above process.

Abstract: A process for producing silicon carbide-base complex is disclosed. In the process of this invention, a silicon carbide-base complex is produced by means of depositing carbon produced by means of pyrolysis of a gas comprising a hydrocarbon or a hydrocarbon halide on a porous synthesized silica glass body. As a result, the process of manufacture according to the present invention is capable of producing a high purity and a high strength silicon carbide-base material, which is useful as a jig for producing semiconductors, for example, a heat resistance jig material such as a process tube for wafer boats used for heat doping operation.

Abstract: Tough ceramic products can be prepared without exotic pressure fabricating techniques by use of a matrix laminate comprising a continuous fiber ceramic reinforcement in tow or woven form for strength, stiffness, and toughness and a ceramic matrix generally comprising (a) a filler, such as mullite; (b) ceramic reinforcing whiskers, such as silicon nitride or silicon carbide, for fine-scale interlaminar shear resistance (c) a binder, such as colloidal silica; and (d) an activator, such as a trona-like material including sodium and carbonate. The matrix is brushed into the fiber reinforcement, which is then laid up, dried, and cured. Tandem ceramic composites can be fabricated.

Abstract: A cermet blade member including a cermet substrate is provided which consists essentially of: 0.2% by weight to 8% by weight of a binder phase of at least one binder metal of cobalt and nickel; 5% by weight to 30% by weight of a first hard dispersed phase of at least one material of zirconia and a stabilized zirconia; and the remainder of a second hard dispersed phase of at least one metal carbo-nitride. The metal of the above-mentioned metal carbo-nitride is selected from metals in Group IVA in a periodic table. In addition, a cermet blade member including the cermet substrate and a hard coating layer formed on the surface of the cermet substrate is provided. The hard coating layer consists of at least one layer of a compound selected from a titanium carbide, a titanium nitride, a titanium carbo-nitride, titanium carbo-oxide represented by TiCO, titanium carbo-oxi-nitride represented by TiCNO and an aluminum oxide.

Abstract: A new silicon carbide material is made following a procedure including hot pressing to provide a finished product having a microstructure with an optimal grain size of less than 7 micrometers. The material exhibits a dominant failure mode of intergranular fracture requiring significant energy for crack propagation. The method of manufacturing is cost-effective by allowing the use of "dirty" raw materials since the process causes impurities to segregate at multi-grain boundary junctions to form isolated pockets of impurities which do not affect the structural integrity of the material. End uses include use as protective projectile-resistant armor.