Abstract: A low temperature process is described for forming a coating or powder comprising one or more metals or metal compounds by first reacting one or more metal reactants with a halide-containing reactant to form one or more reactive intermediates capable of reacting, disproportionating, or decomposing to form a coating or powder comprising the one or more metal reactants. When one or more metal compounds are formed, either as powders or as coatings, a third reactant may be injected into a second reaction zone in the reactor to contact the one or more reactive intermediates formed in the first reaction zone to thereby form one or more metal compounds such as metal nitrides, carbides, oxides, borides, or mixtures of same.

Abstract: Lewis base-borane complexes such as (CH.sub.3).sub.2 S.BHBr.sub.2 are utilized as molecular precursors for the formation of both bulk powders, films and coatings of boron nitride. The complexes are subjected to slow heating under an ammonia atmosphere to displace the base and pyrolyze the resulting complex to BN. Analogous processes may be used to prepare Group IIIA-VA compounds of the formula MM' where M is selected from the group consisting of B, Al, Ga, In, and Tl, and M' is selected from the group consisting of N, P, As, Sb and Bi.

Abstract: The invention encompasses unsintered and sintered compositions comprising boride and alumina. A sintered material containing boride and alumina may be produced by a method comprising:a) combining sources of borate glass frit and aluminum to form a mixture;b) compacting the mixture to form a shape;c) heating the shape, whereby the sources react to form boride and alumina; andd) densifying the reacted shape.Specific embodiments of the invention include the use of rare earth borate glasses such as La.sub.2 O.sub.3. 6 B.sub.2 O.sub.3 glass to form compositions containing rare earth boride.

Abstract: Uniform, fine ceramic powder is prepared using an apparatus comprising (a) a cooled reactant transport member; (b) a reactor chamber; (c) a heating element; and (d) a cooling chamber. The reactant transport member comprises a wall defining a conduit that communicates with the reactor chamber, with a gas-flow space being defined along the perimeter of the transport member and in communication with the reactor chamber. The reactor chamber comprises a wall defining a reaction zone, and the heating element is associated with the reaction zone, and adapted for heating reactants in the reaction zone. The cooling chamber has a wall defining a cooling zone that communicates with the reactor chamber. In one embodiment, the communication is through a cooling inlet, the diameter of the cooling zone being larger than the diameter of the cooling inlet. The temperatures of the reactant transport member, the reactor chamber, and the cooling chamber are independently controllable.

Abstract: A composition and method for producing boron carbide/titanium diboride composite ceramic powders is disclosed. The process comprises the ordered steps of (a) intimately mixing as reactants boron carbide and a titanium source, such that the average reactant particle size is less than about 20 microns and substantially all discrete reactant areas are less than about 50 microns, and (b) reacting the product of step (a) under conditions sufficient to produce a boron carbide/titanium diboride composite ceramic powder wherein at least a portion of the boron carbide particles form substrates to which at least a portion of the titanium diboride particles are attached. The method can be used to produce a composite ceramic powder having boron carbide and titanium diboride particles less than about 20 microns in diameter.

Abstract: A method for making a substantially flexible dry matrix and the result and article capable of cleaning a surface by removing dust and/or organic film and rendering the surface substantially static-free, suitable for use as a garment, air filter or mat, comprising a matrix comprising natural or synthetic, woven, non-woven or knitted fibers, or a flexible foam material, said matrix having been uniformly coated with an amount of treatment solution sufficient to allow said matrix to retain its substantially dry characteristics, said solution comprising between about 25% and 75% of at least one glycol compound, between about 0.2% and 60% of a cationic surfactant, an antimicrobial compound and optionally up to about 45% of a nonionic surfactant may be added to the treatment solution. When removing organic film, the wipe is contacted with water and used to wash the surface, and can then be rung out and used to wipe the surface dry.

Abstract: A method for the manufacture of ultrafine particles or atom clusters is disclosed. The ultrafine particles of size between about 10 to 1000 Angstroms are formed by the disruption of the crystal lattice or micrograin structure of the metal, alloy or intermetallic compound in one or both of two spaced electrodes by a high frequency, high voltage, high peak current discharge. The ultrafine particles are not subjected to fractionation as in evaporative processes and accordingly are remarkably predictable in both particle size, distribution of sizes and atomic composition, and also are readily transportable in carrier gases.

Abstract: Metal boride powders can be produced with a predetermined particle size by controlling reaction conditions. The metal boride powder is produced by reacting a solid boron source, a metal source and a reductant under conditions sufficient to produce a metal boride powder with a particle size correlating to that of the solid boron source. The reaction is preferably stopped after the formation of products but before any appreciable crystal growth occurs.

Abstract: The invention relates to an energy efficient method for the production of boron nitride materials at temperatures of from about 100 degrees to about 230 degrees Centigrade. The boron nitride materials produced by the present invention are carbon-free and are prepared by combining at reduced pressure an alkali metal, such as potassium, rubidium, cesium, or mixtures thereof, or a potassium/sodium mixture, with a boron-, nitrogen-, and halogen-containing material, such as a haloborazine, haloborazane, or haloaminoborane. The preferred boron-, nitrogen-, and halogen-containing materials are trihalogenated, the preferred halogen is chlorine, and the preferred alkali metal is cesium.

Abstract: A powder composition consisting essentially of an intimate mixture of boron carbide and titanium diboride, the mixture having an average particle size of less than about 0.5 micron, the particles being uniformly dispersed such that elemental analytical techniques show all discrete concentrations of boron carbide and titanium diboride to be less than or equal to about 0.5 micron in diameter, is disclosed. The powder is useful for making a densified ceramic composition comprising titanium diboride grains, having an average grain size of less than or equal to about 3 microns in diameter, uniformly dispersed with boron carbide grains, having an average grain size of less than about 5 microns in diameter. The densified composition exhibits improved hardness and toughness when compared wiht titanium diboride or boron carbide compositions.

Abstract: A process for the production of a precursor which is a polymeric material comprising at least one metallic or non-metallic element, oxygen and carbon and from which a ceramic material, e.g. a carbide, nitride, boride, or silicide, may be produced by pyrolysis, which process comprises reacting(1) a first reactant which comprises a compound or compounds of at least one metallic or non-metallic element having two or more groups reactive with hydroxyl groups, and(2) a second reactant which comprises at least one organic compound having two or more hydroxyl groups,said reaction being effected in a liquid medium in which the reactants are soluble and/or dispersible and in which the polymeric material which is produced by the reaction is insoluble or in which the polymeric material may be caused to be insoluble, precipitating the polymeric material in the liquid medium in particulate form, and recovering the polymeric material from the liquid medium in particulate form.

Abstract: The rare earth borides are prepared at relatively low temperatures by reacting a rare earth halide with elemental boron in the presence of a reducing amount of aluminum metal.

Abstract: A process for the production of a refractory boride or silicide which comprises producing an oxygen-containing polymeric product by reacting a compound of the metallic or non-metallic element having two or more groups reactive with hydroxyl groups and a compound of boron or silicon having two or more groups reactive with hydroxyl groups with an organic compound having two or more hydroxyl groups and heating the polymeric product in an inert atmosphere to pyrolyse the polymeric product and produce a refractory boride or silicide of the metallic or non-metallic element.

Abstract: A method of making metal carbide, nitride, or boride powders and mixtures thereof by direct reduction of metal compounds comprises (a) forming a reactant mixture, (b) heating the reactant mixture to temperatures that cause solid reactants to vaporize and above which the metal precursor compounds are reduced, (c) passing the heated reactant mixture through a converging-diverging nozzle designed to reduce the temperature of the mixture to a temperature and for a time sufficient for further product species to form and for nuclei to form and grow by condensation to form the product powders, and (d) exhausting the mixture and product powders from the nozzle into an expansion chamber.

Abstract: A method of producing submicron size boron carbide powder by heating a reactive mixture containing a boric oxide source and a carbon source at a high temperature for a sufficient length of time to form submicron particles of uniform size.

Abstract: A method of synthesizing amorphous Group IIIA-Group VA compounds. A first solution is prepared which consists of a tris(trialkylsilyl) derivative of either a Group IIIA or Group VA element dissolved in an organic solvent. A second solution is then prepared which consists of a halide of the other of the Group IIIA or Group VA element dissolved in an organic solvent. Then the first and second solutions are mixed such that a Group IIIA-Group VA compound is formed along with a trialkylhalosilane by-product. The final step of the method consists of removing the trialkylhalosilane by-product and organic solvent mixture to form the Group IIIA-Group VA condensed phase.

Abstract: The invention relates to a process for the production of porous products of boron or boron compounds.This process comprises the following stages:(1) suspending the boron powder in a solution of an alkali metal salt, hydroxide and/or oxide,(2) then separating the powder from the suspension liquid by settling,(3) drying the thus separated powder to obtain an agglomerated powder, and(4) subjecting the thus obtained agglomerated powder to at least two heat treatments performed at different temperatures, the final stage of the heat treatment being performed at a temperature of 1500.degree. to 2200.degree. C. and the first stage being performed at a temperature below that of the final stage.The heat treatment can be performed in three stages, as shown in the attached graph.

Abstract: Refractory borides or carbides are prepared by contacting an alkali-metal ducible metal chloride or silicon tetrachloride with boron trichloride or carbon tetrachloride in an inert solvent in the presence of an alkali metal, the metal chloride or silicon tetrachloride and the boron trichloride or carbon tetrachloride being present in an amount about stoichiometrically equivalent to the boride or carbide to be prepared and the alkali metal being present in an amount about stoichiometrically equivalent to the amount of chloride in the metal chloride or silicon tetrachloride and the boron trichloride or carbon tetrachloride, until all chloride present has reacted with the alkali metal to form alkali metal chloride, separating the inert solvent to leave a solid residue containing a metal boride, silicon carbide or metal carbide precursor together with the alkali metal chloride, and calcining the residue while separating the alkali metal chloride until the precursor is converted to the refractory boride or carbide

Abstract: Hard, tough, lightweight boron-carbide-reactive metal composites, particularly boron-carbide-aluminum composites, are produced. These composites have compositions with a plurality of phases. A method is provided, including the steps of wetting and reacting the starting materials, by which the microstructures in the resulting composites can be controllably selected. Starting compositions, reaction temperatures, reaction times, and reaction atmospheres are parameters for controlling the process and resulting compositions. The ceramic phases are homogeneously distributed in the metal phases and adhesive forces at ceramic-metal interfaces are maximized. An initial consolidation step is used to achieve fully dense composites. Microstructures of boron-carbide-aluminum cermets have been produced with modulus of rupture exceeding 110 ksi and fracture toughness exceeding 12 ksi.sqroot.in. These composites and methods can be used to form a variety of structural elements.

Abstract: A method of producing an aluminum boride (AlB.sub.2 or AlB.sub.12) in solid form comprises providing a body of molten aluminum containing suspended particles of an aluminum boride, and separating the particles e.g. by filtration from the bulk of the molten metal. Preferred filter media are alumina and carbon, each of which can be subsequently removed to leave the aluminum boride in solid form. The product is a useful precursor for production by reaction sintering of refractory composites containing titanium diboride.

Abstract: A process for producing a free-standing polycrystalline boron phosphide film comprises growing a film of boron phosphide in a vertical growth apparatus on a metal substrate. The metal substrate has a coefficient of thermal expansion sufficiently different from that of boron phosphide that the film separates cleanly from the substrate upon cooling thereof, and the substrate is preferably titanium. The invention also comprises a free-standing polycrystalline boron phosphide film for use in electronic device fabrication.

Abstract: A method and device for conducting gettering. The gettering is conducted with one of an LiB, LiSi or LiAl system. Preferably the LiB system is of the formula Li.sub.x B.sub.1-x wherein 0<x<1 with gettering conducted at room or slightly elevated temperature of about 100.degree.-200.degree. C.

Abstract: TiB.sub.2 -graphite composite articles suitable for use as cathode components in a Hall aluminum reduction cell are made by impregnating a TiO.sub.2 -carbon composite with a boron compound and carbon black dispersed in water, or alternately by impregnating a boron or boron compound-carbon composite with a carbon black-TiO.sub.2 dispersion, and heating the article to a reaction temperature whereby TiB.sub.2 is formed and the amorphous carbon converted to graphite. The article may be impregnated with a carbonizable liquid, re-baked, and re-heated to a graphitizing temperature to increase its strength and density.

Abstract: Metallic phosphates are prepared by heating mixtures of BPO.sub.4 and a metallic oxide or salt.

Abstract: A cathode component for a Hall aluminum cell is economically produced from a mixture of a carbon source, preferably calcined petroleum coke, and optionally calcined acicular needle petroleum coke, calcined anthracite coal; a binder such as pitch including the various petroleum and coal tar pitches; titanium dioxide, TiO.sub.2 ; and boric acid, B.sub.2 O.sub.3 or boron carbide, B.sub.4 C; forming said mixture into shapes and heating to a TiB.sub.2 -forming temperature.

Abstract: Submicron titanium diboride powder and other hard, refractory metal boride powders, such as zirconium diboride and hafnium diboride powders, are prepared by vapor phase reaction of the corresponding metal halide, e.g., titanium halide, and boron source reactants in the presence of hydrogen in a reaction zone and in the substantial absence of oxygen, either combined or elemental. In a preferred embodiment, the metal halide, e.g., titanium tetrachloride, and boron source, e.g., boron trichloride, reactants are mixed with a hot stream of hydrogen produced by heating hydrogen in a plasma heater. The reaction zone is maintained at metal boride forming temperatures and submicron solid metal boride powder is removed promptly from the reactor and permitted to cool. The preponderant number of metal boride particles comprising the powder product have a particle size in the range of between 0.05 and 0.7 microns.

Abstract: Submicron titanium diboride powder and other hard, refractory metal boride powders, such as zirconium diboride and hafnium diboride powders, are prepared by vapor phase reaction of the corresponding metal halide, e.g., titanium halide, and boron source reactants in the presence of hydrogen in a reaction zone and in the substantial absence of oxygen, either combined or elemental. In a preferred embodiment, the metal halide, e.g., titanium tetrachloride, and boron source, e.g., boron trichloride, reactants are mixed with a hot stream of hydrogen produced by heating hydrogen in a plasma heater. The reaction zone is maintained at metal boride forming temperatures and submicron solid metal boride powder is removed promptly from the reactor and permitted to cool. The preponderant number of metal boride particles comprising the powder product have a particle size in the range of between 0.05 and 0.7 microns.

Abstract: A plasma-arc process is disclosed for the production of powders of various chemical products, according to endothermic reactions, such as TiC and the like. The process consists essentially in carrying out, in a furnace with an anodic function without dissipative cooling, a series of steps comprising:(a) forming a chemically reactive fluidodynamic mass having a high thermal content and a high concentration of the desired reactive species, by injecting into the electronic column of a plasma-arc of a noble gas at least one reactant selected from the class consisting of metal and metalloid halides, the injection taking place, with mixing through a choker-injector-mixer nozzle which is electrically insulated;(b) causing the electronic condensation of said mass inside a main nozzle anode without dissipative cooling; and(c) injecting into said electronically condensed mass the residual part of said reactants necessary to the desired main chemical reaction for producing the chemical powder.

Abstract: Anion exchange resins containing borohydride counter ions display essentially the same chemical activity as solutions of sodium borohydride but have the added advantage that products treated therewith are not contaminated with sodium ions or borate ions. Thus, alcohols can now be freed of carbonyl components without thereby being contaminated with borate; metal ions, such as silver, can be reduced to the free element; metal ions of groups IV-A to VI-A can be converted to volatile metal hydrides; and transition metal ions can be converted to the boride. The anion exchange resin is prepared by treating a strong base anion exchanger with aqueous sodium borohydride or sodium cyanoborohydride. Regeneration of the borohydride form from the borate proceeds directly with aqueous sodium borohydride.

Abstract: Finely divided borides, carbides, and nitrides of metals of Groups III-VI of the Periodic Table, formed by reacting vaporous metal halide and a boron, carbon, or nitrogen source reactant at high temperatures, e.g., 1500.degree. C., are separated from gaseous reactor effluent stream at temperatures between about 200.degree. C. and 1500.degree. C. with the use of a porous sintered filter. By separating the finely divided product from the effluent stream before the stream cools to below about 200.degree. C., adsorption of impurities, e.g., unreacted metal halide or metal subhalides, on the product is reduced. The use of a filter, e.g., a porous sintered filter, avoids the size classification of product which may result when cyclones and a bag filter are used to collect product.

Abstract: A polycrystalline silicon body is produced by forming a particulate mixture of silicon powder having an average particle size less than 3 microns and boron in an amount ranging from 0.1% to 5% by weight of the silicon powder, shaping the particulate mixture into a green body and sintering the body to a density of at least 60% of the theoretical density of silicon.

Abstract: A novel catalyst material of a boron containing substance for catalyzing the liquid phase oxidation of an olefin with an organic hydroperoxide to the corresponding oxirane is disclosed. The novel catalyst materials are characterized as binary or ternary boride compounds having the general formula M.sub.x B.sub.y or M.sub.x B.sub.y R.sub.z wherein x is an integer from 1-5; y is an integer from 1-2; z is an integer from 1-4; B is boron; M is an element selected from the groups II-A, III-B, IV-B, V-B, VI-B, VII-B, VIII, III-A, IV-A, and V-A of the Periodic Table, the rare earths, and the actinides; and R is an element different from M selected from the same group of elements in the Periodic Table as M. The preferred catalyst materials are those boron containing substances which are substantially insoluble in the reaction mixture containing the organic hydroperoxides, olefins and products.

Abstract: A method for preparing single crystals of lanthanum hexaboride (LaB.sub.6) by arc melting a rod of compacted LaB.sub.6 powder. The method is especially suitable for preparing single crystal LaB.sub.6 cathodes for use in scanning electron microscopes (SEM) and scanning transmission electron microscopes (STEM).

Abstract: A flexible electromagnetic shield is provided. The shield comprises interlaced filaments of at least one glassy metal alloy. The glassy alloy has a maximum permeability of at least about 50,000 and a coercivity of less than about 0.08 Oe.

Abstract: The preparation of metal and metalloid carbides, borides, nitrides silicides and sulfides by reaction in the vapor phase of the corresponding vaporous metal halide, e.g., metal chloride, with a source of carbon, boron, nitrogen, silicon or sulfur respectively in a reactor is described. Reactants can be introduced into the reactor through a reactant inlet nozzle assembly. Inhibition and often substantial elimination of product growth on exposed surfaces of such assembly is accomplished by introducing the corresponding substantially anhydrous hydrogen halide, e.g., hydrogen chloride, into the principal reactant mixing zone.