Abstract: Apparatus and methods for curing composite compositions that react with CO2. The apparatus in general includes an easily transportable and easily assembled curing structure, such as a plastic sheet housing supported by gas pressure and/or by mechanical supports. Apparatus for providing reagent CO2, for measuring water content and for removing water, and for controlling temperature, flow rates and flow directions through the curing structure. Examples of curing procedures and examples of cured materials in desired shapes are described.

Abstract: The invention provides novel articles of composite materials having hollow interior channels or passageways, or otherwise being hollowed out, and formulations and methods for their manufacture and uses. These hollow core objects are suitable for a variety of applications in construction, pavements and landscaping, and infrastructure.

Abstract: The invention provides novel articles of composite materials having hollow interior channels or passageways, or otherwise being hollowed out, and formulations and methods for their manufacture and uses. These hollow core objects are suitable for a variety of applications in construction, pavements and landscaping, and infrastructure.

Abstract: The invention provides novel articles of composite materials having hollow interior channels or passageways, or otherwise being hollowed out, and formulations and methods for their manufacture and uses. These hollow core objects are suitable for a variety of applications in construction, pavements and landscaping, and infrastructure.

Abstract: The invention provides novel articles of composite materials having hollow interior channels or passageways, or otherwise being hollowed out, and formulations and methods for their manufacture and uses. These hollow core objects are suitable for a variety of applications in construction, pavements and landscaping, and infrastructure.

Abstract: The invention provides novel articles of composite materials having hollow interior channels or passageways, or otherwise being hollowed out, and formulations and methods for their manufacture and uses. These hollow core objects are suitable for a variety of applications in construction, pavements and landscaping, and infrastructure.

Abstract: The invention provides novel articles of composite materials having hollow interior channels or passageways, or otherwise being hollowed out, and formulations and methods for their manufacture and uses. These hollow core objects are suitable for a variety of applications in construction, pavements and landscaping, and infrastructure.

Abstract: Apparatus and methods for curing composite compositions that react with CO2. The apparatus in general includes an easily transportable and easily assembled curing structure, such as a plastic sheet housing supported by gas pressure and/or by mechanical supports. Apparatus for providing reagent CO2, for measuring water content and for removing water, and for controlling temperature, flow rates and flow directions through the curing structure. Examples of curing procedures and examples of cured materials in desired shapes are described.

Abstract: Polycrystalline materials of macroscopic size exhibiting Single-Crystal-Like properties are formed from a plurality of Single-Crystal Particles, having Self-Aligning morphologies and optionally ling morphology, bonded together and aligned along at least one, and up to three, crystallographic directions.

Abstract: Polycrystalline materials of macroscopic size exhibiting Single-Crystal-Like properties are formed from a plurality of Single-Crystal Particles, having Self-Aligning morphologies and optionally ling morphology, bonded together and aligned along at least one, and up to three, crystallographic directions.

Abstract: A method for fabricating a triphasic composite such as a WC/Co/diamond composite with a high volume fraction of diamond in a WC/Co matrix. The method involves sintering of a WC/Co powder compact to develop a porous preform, which displays some rigidity and strength, infiltrating the porous preform with a controlled distribution of carbon, and high pressure/high temperature treatment of the carbon-containing WC/Co preform to transform the carbon to diamond. The distribution of diamond in the composite can be functionally graded to provide a WC/Co core and a diamond-enriched surface, wherein all three phases form an interconnected structure in three dimensions. Such a tricontinuous structure combines high strength and toughness with superior wear resistance, making it attractive for applications in machine tools and drill bits.

Abstract: A method for fabricating a triphasic composite such as a WC/Co/diamond composite with a high volume fraction of diamond in a WC/Co matrix. The method involves sintering of a WC/Co powder compact to develop a porous preform, which displays some rigidity and strength, infiltrating the porous preform with a controlled distribution of carbon, and high pressure/high temperature treatment of the carbon-containing WC/Co preform to transform the carbon to diamond. The distribution of diamond in the composite can be functionally graded to provide a WC/Co core and a diamond-enriched surface, wherein all three phases form an interconnected structure in three dimensions. Such a tricontinuous structure combines high strength and toughness with superior wear resistance, making it attractive for applications in machine tools and drill bits.

Abstract: A low melting point alloy is used to sinter metal carbide particles. The alloy is a eutectic-like alloy formed from a binding metal such as iron, cobalt or nickel, in combination with vanadium and chromium. The alloy is preferably formed by forming two separate alloys and blending these together. The first alloy is formed by spray drying together a solution of a binding metal salt such as a cobalt salt with a solution of a chromium salt. The formed particles are then carburized to form a cobalt-chromium-carbon alloy. A separate vanadium alloy is formed in the same manner. The two are combined to establish the amount of chromium and vanadium desired, and this, in turn, is used to sinter metal carbide parts. This permits sintering of the metal carbide parts at temperatures less than 1250.degree. C. and in turn significantly inhibits grain grown without a significant decrease in toughness. It is particularly adapted to form carbide products wherein the carbide grain size is as low as 120 nanometers.

Abstract: Amorphous tungsten, cobalt, nickel, molybdenum, iron and alloys thereof can be formed by reducing metal-containing compositions to form the elemental metal wherein the particle size of the elemental metal is less than about 80 microns. This is oxidized in an oxygen-starved environment containing less than 3% oxygen and an inert gas to slowly oxidize the elemental metal. By oxidizing the metal under these conditions, the normal exotherm occurring during oxidation is avoided. The slow oxidation of the metal continues forming an amorphous metal oxide. The amorphous metal oxide can then be reacted in a reducing environment such as hydrogen to form the amorphous elemental metal. This amorphous elemental metal can then be reacted with a carburizing gas to form the carbide or ammonia gas to form the nitride or hexamethylsilane to form the silicide. This permits gas/solid reactions. The amorphous metal can also be used in a variety of different applications.

Abstract: A compacted, single phase or multiphase composite article. Particles for use in the compacted article are produced by providing a precursor compound containing at least one or at least two metals and a coordinating ligand. The compound is heated to remove the coordinating ligand therefrom and increase the surface area thereof. It may then be reacted so that at least one metal forms a metal-containing compound. The particles may be consolidated to form a compacted article, and for this purpose may be used in combination with graphite or diamonds. The metal-containing compound may be a nonmetallic compound including carbides, nitrides and carbonitrides of a refractory metal, such as tungsten. The metal-containing compound may be dispersed in a metal matrix, such as iron, nickel or cobalt. The dispersed nonmetallic compound particles are no larger than about 0.1 micron in particle size and have a volume fraction greater than about 0.15 within the metal matrix.

Abstract: A new carbothermic reaction process is described for the thermochemical processing of nanophase WC-Co powders. The process permits shorter reaction times, reduced temperatures, and finer microstructures compared to conventional processing methods.The process builds on our experience with spray conversion processing [1], but involves 1) chemical vapor infiltration reaction of the carbon infiltrant and particle substrate to from WC-CO; and 2) removal of any excess (unreacted) carbon by controlled gasification. A feature of the carbothermic reaction process is its adaptability to conventional WC-Co processing technology, as well as to spray conversion processing technology.The resulting power particles consist of a network of fine grains, (less than 100 nm) of WC and Co with interconnected fine porosity. Powder particles suitable for subsequent handling and consolidation are readily produced with diameters greater than 10 microns.

Abstract: A compacted, single phase or multiphase composite article. Particles for use in the compacted article are produced by providing a precursor compound containing at least one or at least two metals and a coordinating ligand. The compound is heated to remove the coordinating ligand therefrom and increase the surface area thereof. It may then be reacted so that at least one metal forms a metal-containing compound. The particles may be consolidated to form a compacted article, and for this purpose may be used in combination with graphite or diamonds. The metal-containing compound may be a nonmetallic compound including carbides, nitrides and carbonitrides of a refractory metal, such as tungsten. The metal-containing compound may be dispersed in a metal matrix, such as iron, nickel or cobalt. The dispersed nonmetallic compound particles are no larger than about 0.1 micron in particle size and have a volume fraction greater than about 0.15 within the metal matrix.

Abstract: A compacted, single phase or multiphase composite article. Particles for use in the compacted article are produced by providing a precursor compound containing at least one or at least two metals and a coordinating ligand. The compound is heated to remove the coordinating ligand therefrom and increase the surface area thereof. It may then be reacted so that at least one metal forms a metal-containing compound. The particles may be consolidated to form a compacted article, and for this purpose may be used in combination with graphite or diamonds. The metal-containing compound may be a nonmetallic compound including carbides, nitrides and carbonitrides of a refractory metal, such as tungsten. The metal-containing compound may be dispersed in a metal matrix, such as iron, nickel or cobalt. The dispersed nonmetallic compound particles are no larger than about 0.1 micron in particle size and have a volume fraction greater than about 0.15 within the metal matrix.

Abstract: A process is described for the production of composite powders with ultrafine microstructures. The process involves three coordinated steps:1) preparation and mixing of an appropriate starting solution;2) spray drying to form a chemically homogeneous precursor powder; and3) fluid bed thermochemical conversion of the precursor into the desired nanophase composite powder.Both spray drying and fluid bed conversion are scaleable technologies, and together provide the means for producing bulk quantities of nanophase composite powders at low manufacturing cost. Processing parameters are controlled to ensure maintenance of chemical and microstructural uniformity at the nanoscale (less than 0.1 micron) level.Spray conversion processing is a versatile technology, which can be applied to a variety of metal--metal (e.g. W--Cu), ceramic-metal (e.g. WC--Co), and ceramic--ceramic (e.g. Al.sub.2 O.sub.3 --SiO.sub.2) nanophase composite powders ceramic-metal (e.g. WC--Co), and ceramic--ceramic (e.g. Al.sub.2 O.sub.3 --SiO.

Abstract: A compacted, single phase or multiphase composite article. Particles for use in the compacted article are produced by providing a precursor compound containing at least one or at least two metals and a coordinating ligand. The compound is heated to remove the coordinating ligand therefrom and increase the surface area thereof. It may then be reacted so that at least one metal forms a metal-containing compound. The particles may be consolidated to form a compacted article, and for this purpose may be used in combination with graphite or diamonds. The metal-containing compound may be a nonmetallic compound including carbides, nitrides and carbonitrides of a refractory metal, such as tungsten. The metal-containing compound may be dispersed in a metal matrix, such as iron, nickel or cobalt. The dispersed nonmetallic compound particles are no larger than about 0.1 micron in particle size and have a volume fraction greater than about 0.15 within the metal matrix.