摘要:
The present invention is directed towards a ceramic nanocomposite comprising a nanostructured carbon component inside a ceramic host. The ceramic nanocomposite may further comprise vapor grown carbon fibers. Such nanostructured carbon materials impart both structural and thermal barrier enhancements to the ceramic host. The present invention is also directed towards a method of making these ceramic nanocomposites and for methods of using them in various applications.
摘要:
A ceramic material suitable for use in production of paving tiles, construction tiles, flooring in offices, flooring in machinery plants and so forth is obtained by a method comprising steps of mixing defatted bran derived from rice bran with a thermosetting resin before kneading, subjecting a kneaded mixture thus obtained to a primary firing in an inert gas at a temperature in a range of 700 to 1000null C., pulverizing the kneaded mixture after the primary firing into carbonized powders, kneading the carbonized powders with which ceramic powders, a solvent, and a binder as desired are mixed into a plastic workpiece (kneaded mass), pressure-forming the plastic workpiece at pressure in a range of 10 to 100 MPa, and subjecting a formed plastic workpiece thus obtained again to firing in an inert gas atmosphere at a temperature in a range of 100 to 1400null C.
摘要:
An essentially non-slumping sprayable refractory castable composition that is applied without forms is disclosed comprising (a) a tempered, pumpable first component comprising (i) one hundred weight percent of a refractory composition comprising from about 60 to 90 weight percent of a refractory aggregate, from about 2 to 25 weight percent of an ultrafine refractory material having an average particle diameter size less than or equal to about 3 microns, from about 0.5 to 15 weight percent of a binder, and from about 0.05 to 2.0 weight percent of a dispersant, wherein all or a portion of the ultrafine refractory material comprises a thermal black such that the refractory composition comprises from about 2 to 15 weight percent of the thermal black, and (ii) from about 3 to 10 weight percent water based upon 100 weight percent of the refractory composition; and (b) a second component comprising a flocculating agent, wherein the second component is added to the first component for achieving installation of the sprayable refractory castable composition in an amount to prevent slumping. A method of installing the sprayable refractory castable composition is also disclosed.
摘要:
The present invention is a composite material, a process and a product formed by the process. The composite is formed by a process that includes forming a fibrous structure comprising fibers into a preform, coating the fibers of the fibrous structure preform with elemental carbon to impregnate that preform, infiltrating the preform with boron carbide to form an impregnated green body. The impregnated green body is infiltrated with liquid naphthalene or other carbon precursor, which is thereafter pyrolyzed to form a carbon char. Then, the char infiltrated green body is infiltrated with molten silicon to form a continuous matrix throughout the composite. The silicon in the continuous matrix is reacted with the carbon char to form silicon carbide.
摘要:
Refractories obtained by molding a refractory raw material composition containing a refractory raw material including graphite grains having an average grain size of 500 nm or less or a refractory raw material including graphite grains obtained by graphitizing carbon black and a refractory filler. Or refractories containing carbonaceous grains (A) selected from carbon black or graphite grains obtained by graphitizing carbon black and having a DBP absorption (x) of 80 ml/100 g or more, carbonaceous grains (B) selected from carbon black and graphite grains obtained by graphitizing carbon black and having a DBP absorption (x) of less than 80 ml/100 g, and a refractory filler. Refractories excellent in corrosion resistance, oxidation resistance and thermal shock resistance, especially carbon-contained refractories having a low carbon content are thereby provided.
摘要:
An electroconductive low thermal expansion ceramic sintered body is disclosed which containing a null-eucryptite phase in a quantity of not less than 75 vol. % and not more than 99 vol. % and having an absolute value of thermal expansion coefficient of not more than 1.0null10null7/K at a temperature of 0null C. to 50null C., a volumetric specific resistance of not more than 1.0null107 nullnullcm, and a specific rigidity of not less than 40 GPa/g/cm3.
摘要:
A carbonaceous refractory material is produced by adding an organic binder to a mixture containing a carbonaceous material comprising a carbonaceous raw material comprising calcined anthracite, calcined coke, artificial graphite or natural graphite or a mixture thereof at 50 to 85% as the principal raw material, alumina particle at 5 to 15%, metal silicon particle at 5 to 15%, and one or two or more of titanium carbide powder, titanium nitride powder and titanium carbonitride powder at 5 to 20% in total, kneading and molding the resulting mixture and baking the molded article under non-oxidizing atmosphere. By using the carbonaceous refractory material as the inner lining material for the side wall and bottom of blast furnace hearth, the consumption of the inner lining material due to the dissolution thereof in melted pig iron can be decreased, and simultaneously, the abrasion due to the flow of melted pig iron can be decreased, which works to prolong the life of the blast furnace.
摘要:
An improved submerged entry nozzle is provided which is useful in the casting of aluminum killed molten steel. The nozzle has an improved slagline sleeve or collar which surrounds the outer portion of the nozzle to protect it from corrosion during the casting process. The slagline sleeve is made from resin bonded zirconia/graphite which has been formulated so that upon curing of the resin to form resite, there is a reduction in the contractile tendency which results in a reduction in stress fracturing. The reduction of the contractile tendency and the resulting resistance to stress fracturing is achieved by adding an effective amount of calcium oxide to the resin-zirconia-graphite mixture which is used to form the sleeve.
摘要:
A filler sand for a ladle tap hole valve contains 45 to 55 mass % of zircon sand, 30 to 40 mass % of chromite sand and 10 to 20 mass % of silica sand and is blended externally with 0.05 to 5 mass % of carbon black calculated based on the total amount of the sands; or contains 30 to 90 mass % of chromite sand and 10 to 70 mass % of silica sand and is optionally blended externally with 0.05 to 5 mass % of carbon black, wherein 95 mass % or more of the chromite sand consists of particles having diameters falling within a range of 150 to 850 nullm, 60 mass % or more of the chromite sand consists of particles having diameters falling within a range of 212 to 600 nullm, 95 mass % or more of the silica sand consists of particles having diameters falling within a range of 300 to 1180 nullm, and 90 mass % or more of the silica sand consists of particles having diameters falling within a range of 600 to 1180 nullm.
摘要:
The present invention relates to a process of making silicon-silicon carbide ceramic using biopreform derived from monocotyledonous caudex plant stem. The present invention also provides a siliconnullsilicon carbide ceramic made using a biopreform derived from monocotyledonous caudex plant stem.