|
Method of obtaining self-restoring layer on component from composite carbon/carbon material Invention relates to application of coatings for protection against oxidation of components from thermostructured carbon-containing composite materials. In order to obtain self-restoring layer on component from composite material, on component applied is composition, which contains suspension of colloid silicon dioxide, boron or boron compound in form of powder, silicon carbide in form of powder, silicon in form of powder and at least one super-heat-resistant oxide: Y2O3, HiO2, Al2O3, ZrO2. Composition is applied on component in form of successive layers with intermediate drying with further thermal processing for surface vitrification at temperature 600-1000°C. |
|
Invention relates to field of aviation and space technology, mainly, to production of heat-proofing coatings, which can be applied for application on external or internal surface of envelopes from silicon nitride of antenna nose cones of rockets. Heat-proofing coating, includes, wt %: silica filler 36-58; alumoborophosphate binding agent 30-34; Al2O3·3SiO2 1-10; Al2O3·2SiO2 1-10; sodium oxide 1-2, magnesium oxide 1-2; aluminium oxide 1-3; silicon nitride 1-2; boron oxide 2-3; boron nitride 1-3. |
|
Method of producing products from compositional material Invention relates to field of products from compositional material. In accordance with claimed method galvanic coating is applied on carbon blank from carbide-forming metal or alloy of metals and thermo-processing is carried out in vacuum or protective gas medium with carbidisation of galvanic coating. As carbide-forming metal, titanium, niobium, zirconium, tungsten, tantalum, hafnium or alloy of tantalum and hafnium can be applied. |
|
Invention relates to ceramic building materials and can be applied in engobing of brick, tiling, tile. Engobe contains Cambrian clay, broken glass and neutralised galvanic sludge with humidity 80% with the following ratio of components, wt %: Cambrian clay 34.0-36.0; broken glass 14.0-20.0; neutralised galvanic sludge with humidity 80% 46.0-50.0. Galvanic sludge is product of purification of galvanic production sewage waters and consists of molecular and colloidal particles of chromium, iron, nickel, copper, zinc hydroxides, as well as phosphates and sulfates. Engobe has brown colour. |
|
|
Material having multilayer structure and intended for contact with liquid silicon Present invention relates to novel materials having a multilayer structure, intended for contact with liquid silicon in melting and hardening processes thereof, particularly growing silicon crystals for use in photovoltaic applications. An element of the material includes a first (supporting) layer with open porosity of 25-40%, consisting of graphite granules with size of 1-10 mcm; a surface layer formed from silicon carbide, and an intermediate layer formed by a silicon carbide matrix containing at least one carbon inclusion. Volume content of silicon carbide in that layer is equal to 45-70%, which corresponds to volume content of the original porosity of graphite which forms the supporting layer, multiplied by at least 1.2. The method involves preparing an element of the material, having an outer layer of graphite granules with size of 1-10 mcm, with thickness of at least 1000 mcm and porosity of 25-40 vol. %; bringing the element into contact with liquid silicon, holding for 10 minutes to 1 hour at temperature of 1410-1500°C, bringing the element to temperature of 1500-1700°C and holding for 1 to 8 hours in order to form a surface layer and an intermediate layer. |
|
Method of making articles from refractory ceramic material for microwave electronic equipment Invention relates to a method of making articles from refractory ceramic material for use in microwave electronic equipment: furnace muffler, trays and components thereof. The surface of aluminium oxide particles is moistened with a surfactant, the aluminium oxide particles are mixed with kaolin in ratio of 3:1 (by weight) to obtain a homogeneous mixture of given composition, workpieces of the articles are formed by cold moulding, dried at normal temperature and fired in an oxidative medium as follows: raising temperature to 1650±20°C at a rate of 50±5°C/h, isothermic aging at that temperature for 3.0±0.5 hours and cooling to normal temperature at the same rate. Zirconium hydroxide sol with density of 1100-1180 kg/m3 and thickness of 1-3 mcm is applied onto the fired workpieces, completely dried at normal temperature and fired in an oxidative medium as follows: raising temperature to 1650±20°C at a rate of 100±5°C/h, isothermic aging at that temperature for 3.0±0.5 hours and cooling to normal temperature at the same rate. |
|
Invention relates to engobe compositions which can be used in making household ceramic articles. The engobe contains the following components, wt %: white-burning clay 80.5-85.8; ground scrap window sheet glass 6.5-7.5, colouring additive 0.5-5.0; cryolite 0.5-0.9, alumina 5.5-6.5. |
|
|
Method of impregnating crucibles and fireproof products Invention relates to fireproof crucibles, used for melting metal alloys. Method of hermetisation of surface and structure of fireproof crucible with ceramic material includes stages at which: (a) fireproof crucible is heated to specified temperature; (b) dampening substance is applied on crucible surface; (c) ceramic slurry is applied on internal surface of crucible; (d) crucible is vacuumised; (e) excess of slurry is removed from internal surface of crucible; (f) crucible is heated to remove moisture from it; and (g) crucible is burned at temperature from 1300°C to about 1700°C. In case of necessity operations (b)-(f) are repeated many times. Ceramic slurry with viscosity 100-3500 centipoise consists of water, dampening substance and about 20-80 wt % of ceramic powder which has particle size mainly smaller than 1 mcm. Ceramic powder is selected from group MgO-ZrO2, Y2O3-ZrO2, non-stabilised ZrO2, CrO3, Al2O3 or their combinations. |
|
|
Porous fireproof material for obtaining glass, method of its obtaining and application Claimed invention relates to method of obtaining porous fireproof material, to porous fireproof material and can be used for obtaining glass in contact with glass mass. One or several reducers, which at temperature of glass obtaining react with oxygen with formation of oxide, are introduced into fireproof material. Said reducers replace, at least, part of pore volume, with surface tension of fireproof material changing with respect to oxidatively acting glass mass in such a way that in glass obtaining penetration of glass mass into pore volume of fireproof material decreases in processed by reducers areas in comparison with unprocessed areas. Reducers represent organic or inorganic substances. Organic reducers are selected from group, consisting of oil, alcohol, metal alcoholates, wax and their mixture. Aluminium and tin are used as inorganic reducers. Gaseous reducers, which are introduced from outside by means of discharge chambers applied outside, can be used in the method. |
|
Invention relates to engobe compositions which can be used in making ceramic articles for decorative and art purposes. The engobe contains the following components, wt %: white-burning clay 68.0-81.3; scrap glass 5.0-7.0; colouring additive 0.5-15.0; barite 10.0-15.0. The colouring additive used can be ochre, cobalt oxide, chromium oxide or antimony oxide. The engobe additionally contains carboxymethyl cellulose in amount of 0.1-0.2 wt %. |
|
|
Invention relates to engobe compositions which can be used in making household ceramic articles (dishes, casks, jars, racks etc). The engobe contains the following components in wt %: clay 74.0-85.0; ground scrap window sheet glass 3.0-4.0; colouring additive 0.5-9.0; talc 9.0-13.0. The disclosed engobe has heat resistance of 200°C. |
|
|
Protective glassceramic coating for sic-containing materials and method of making said coating Invention relates to chemical industry, heat power engineering, aerospace engineering, and particularly to a protective glassceramic coating for SiC-containing materials and a method of making said coating. The protective glassceramic coating for SiC-containing materials contains yttrium, aluminium and silicon oxides and HfO2 with the following ratio of components (mol. %): Y2O3-10-12; Al2O3-14-17; HfO2-1-5; SiO2 - the balance. The method involves preparation of a solution with viscosity of 2-4 mPa·s from mixtures of organoelement compounds of silicon and aluminium and soluble salts of yttrium and hafnium, layer by layer deposition thereof on SiC-containing material via multiple immersion into the solution. The material is extracted at a rate of 5-10 cm/min. Each layer is dried at temperature 70-80°C and heat treatment is carried out at 1450-1550°C in a neutral medium, held at that temperature for 1-2 hours, cooled to 1150-1250°C and then held at that temperature for 1-2 hours. The material is then cooled to room temperature. |
|
Method of producing protective coatings on articles with carbon-containing base Invention relates to production of carbon articles and materials and is meant for protecting articles operating in oxidative medium conditions at high temperatures, for example in metallurgy industry, aircraft building and other industries, from oxidation. The method involves formation on the surface of the article of a slurry coating based on a composition consisting of a mixture of fine powder of carbon and a refractory metal or compound thereof and a binder, heating the article in silicon vapour in a vacuum in the volume of a reactor with subsequent ageing and cooling. The refractory metal or compound thereof used is Mo and/or W and/or "И", and/or Zr and/or Hf, which are active towards silicon, and/or compounds thereof such as carbides and lower silicides of these metals, e.g., Mo2C, MoC, W2C, WC, TiC, ZrC, HfC, Mo5Si3, W5Si3, Ti5Si3, Zr5Si3, Hf5Si3 or similar. The article is heated in silicon vapour at pressure 1-36 mm Hg to temperature 1500-1750°C and held in said temperature interval and pressure for 1-3 hours, after which the article is cooled in silicon vapour. Heating from 1000°C to 1500-1750°C is preferably carried out at a rate of not more than 150°/h with isothermic ageing at temperatures where chemical reactions for forming silicides are intense. |
|
Invention relates to the technology of silicates and compositions of ceramic mixtures which can be used in engobing ceramic articles. The ceramic mixture for engobing contains the following in wt %: kaolin 43.5-51.3; clay 39.0-43.0; marble flour 0.6-1.2; potsherd 4.0-6.0; dolomite 0.1-0.2; nepheline 4.0-6.0; carboxymethyl cellulose 0.1-0.2; liquid potassium glass 0.3-0.5. |
|
|
Method of producing non-metal casting Proposed method relates to production of non-metal components for construction structures, heat engineering assemblies and chemical hardware with aggressive working media. Non-metal materials are fused and melt is poured into mould. Produced cast is cooled by sprinkling with water to 670-950°C for solid particles of aluminium to be charged on cast surface. Aluminium on cast surface is fused by cast heat to create 1-9 mm-thick aluminium melt layer on cast surface. Then, said melt is blown by air at melt temperature of 10-600°C unless complete oxidation of aluminium and production of component. Air temperature is decreased at aluminium layer smaller thickness and increased at larger thickness. |
|
|
Invention relates to refractory materials and engineering ceramics and can be used in production of refractory ceramic articles, including industrial containers used during synthesis of high-purity materials based on niobiuim and tantalum pentaoxides, as well as for refractory lining of chemical apparatus, furnaces and structural elements. The refractory ceramic article has a base made from several flat blocks of quartz ceramic with moderate porosity, between which there are seams filled with solder of niobium or tantalum pentaoxide, and an outer coating of niobiuim or tantalum pentaoxide applied on the base. The edges of the blocks of the base are rounded and the corners of the blocks are smoothed. The solder in the seams has a double-tee cross-section with concave sides of the support. The width of the seam is not greater than twice the thickness of the block. The spherical radius of the edges of the blocks is not greater than half the thickness of the block. |
|
Invention can be implemented as protection from oxidation of ceramic composite materials for parts of hot routs of perspective gas-turbine installations (GTI) and gas-turbine engines (GTE) of transport systems and power engineering operating under effect of oxidising mediums and fuel combustion products at temperature up to 1600°C. High temperature coating has the following chemical composition, wt %: silicon 10-14, boron 3-7, hafnium oxide 50-60, hafnium boride 12-19, boron carbide 8-14. |
|
|
Layer or coating and composition for applying said layer or coating Present invention relates to a composition for applying a layer of coating, particularly an anti-adhesion layer for casting moulds which are in contact with molten metals or glass. The composition contains aluminium titanate or silicon nitride with average particle size greater than 500 nm, an oxide inorganic component with average particle size between 100 nm and 10 mcm and a binding agent which contains particles with average size less than 50 nm. When preparing the composition, aluminium titanate or silicon nitride is dispersed in water and the obtained dispersion is mixed with aqueous dispersions of an inorganic oxide component, binding agent and additional components. The oxide component can be aluminium oxide or titanium oxide and the additional components can be boron nitride or graphite. The invention also relates to use of the composition to apply a layer or a coating on fire bricks, graphite or steel articles, to layers or coatings applied from this composition, to articles which are at least coated with the said layer or coating. |
|
|
Invention relates to heat-resistant nonmetallic materials and can be used to make effective protective coatings of heating elements based on lanthanum chromite working in an air atmosphere. The invention involves use of a heat-resistant mixture composed of lanthanum chromite, frits from oxide phases and aluminoborosilicate glass with the following ratio of ingredients, in wt %: lanthanum chromite 32-44, frit 43-48, aluminoborosilicate glass 13-20. The frit from oxide phases contains the following components, in wt %: yttrium oxide Y2O3 63-65, aluminium-magnesium spinel MgAl2O4 13-21, lanthanum aluminate LaAl11O18 6-13, mullite Al6Si2O13 6-13, aluminoborosilicate glass SiO2 53-55, CaO 18-20, Al2O3 13-15, B2O3 9-11, MgO 2-4. The multicomponent material for protective coatings obtained from the mixture contains crystalline phases and a glass phase in the following ratio, in wt %: LaCrO3 29-42, Y2O3 30-31, MgAl2O4 6-8, LaAl11O18 3-5, Al6Si2O13 3-5, aluminoborosilicate glass phase 16-22. |
|
Protective coat contains liquid potassium glass and powdery fillers, at the following ratio of components in weight parts: liquid potassium glass - 100-150, silicon carbide - 100-200, graphite - 1-12, sodium fluorsilicate - 0-12. |
|
|
Method for manufacturing of composite material In manufacturing of a composite material, a carbon-base filling cloth is used as a material blank impregnated with a compound of liquid Bakelite 100 weight fractions, isopropyl alcohol 54-100 weight fractions, tetraethoxysilane 44-160 weight fractions and water 7-32 weight fractions. Thereafter drying, consolidation and thermal processing at temperature 1800-2000°C with formation of silicon carbide follow. |
|
Method of preparing super-hard coated abrasive Described is a method of preparing a super-hard coated abrasive, specifically a coated abrasive based on diamond or cubic born nitride (cBN). When realising this method, an inner layer of an element which is capable of (individually or combined with other elements) forming carbides, nitrides or borides is deposited onto the surface(s) of abrasive material at the first stage through a hot coating method. The hot coating method is selected from a group a group comprising a method of depositing from gaseous phase via thermal decomposition of metal halides, a method of chemical deposition from vapour phase and a thermal diffusion coating method. Vanadium, molybdenum, tantalum, indium, zirconium, niobium, tungsten, aluminium, boron and silicon are usually used for depositing the inner layer. Through reactive sputtering using a reactive gas, the inner layer is coated with at least one outer layer made from material selected from a group comprising metal carbides, metal nitrides, metal borides, metal oxides and carbonitrides, boronitrides and borocarbonitrides of metals, for example carbide or nitride of titanium, silicon or aluminium. |
|
|
Composition for manufacturing carbon silicon-carbide material Siliconising composition includes the following components, parts by weight: liquid bakelite BZh3 - 100, isopropyl alcohol - 67-100, tetraethoxysilane - 53-160, water - 11-32. |
|
|
Invention relates to composition of ceramic thermal barrier, used in machine units from superalloy. Composition contains base from zirconium oxide, at least one trivalent oxide from group containing erbium oxide, europium oxide, praseodymium oxide, terbium oxide, holmium oxide and their mixtures, allowing to stabilise zirconium oxide and optimally reduce zirconium oxide heat conductivity, and at least one pentavalent oxide from group: niobium oxide, tantalum oxide or their mixture, allowing to reduce number of oxygen vacancies in such way that it was in fact equal to number of oxygen vacancies in partially stabilised zirconium oxide. Said trivalent oxide is present in molar concentration created by the first part, allowing partial stabilisation of zirconium oxide, and by the second part, which introduces point defects into grid, said pentavalent oxide being present in molar concentration equal to molar concentration of said second part of trivalent oxide. |
|
Method of ceramic item engobing Invention concerns ceramic item production, mainly of ornamental purpose. Method of ceramic item engobing involves application of engobing coating onto twisted textile fiber with further fiber positioning fiber onto an item surface, drying and glazing. Twisted textile fiber can be divided in lengthwise sections coated with angobe layer of different colours. Engobing utilises twisted organic textile fiber burned out later during glazing. |
|
|
Method for processing of fire-resistant products Invention is related to production of fire-resistant products and may be used in aviation and rocket engineering. Technical result is achieved by layerwise saturation of refractory material surface with carbon by means of fullerene solution impregnation in organic dissolvent. Product is placed above heating element so that temperature of saturated surface does not exceed 60-65°C, fullerene solution is supplied in organic dissolvent onto product surface so that complete surface is wetted, and impregnation is carried out for 30-45 minutes. |
|
|
Method of manufacturing of pottery ware and ceramic product Process of decoration of ceramic ware may be used in creation of various ceramic products possessing decorative and decorative - utilitarian function. Method of manufacturing of pottery wares includes product forming out of loamy raw material, preliminary drying reaching leather - solid state, decoration with colored engobes, final drying and burning. During process of decoration spot of application of background engobe is restricted by at least one local spot, formed by one closed circuit of cutting, at least, one layer of background engobe of the color contrast to that of the foundation is applied on the foundation; there after the product is dried and texturised by cutting of the background layer with applied engobes uncovering foundation of the product; there after received decorative elements are painted with multicolored engobes and refreshed by additional cutting getting as a result corresponding ceramic product. Cutting is conducted with V-shaped profile and/or V-shaped profile and undercutting and/or rounding - off of the profile uncovering foundation of the product. |
|
|
Carbon material coated in tantalum carbide and method of obtaining it Invention pertains to carbon material coated in tantalum carbide, which can be used as a component part of a device for making monocrystals of binary semiconductor compounds. According to the invention, carbon material consists of carbon substrate and film, formed indirectly or through intermediate layer on the above mentioned carbon substrate. The film is 10-100 mcm thick and consists of several tightly packed monocrystals of tantalum carbide. On an X-ray diffraction pattern of the film, the diffraction intensity of plane (220) of tantalum carbide has a maximum level. The above mentioned diffraction intensity is not less than 4 times more than the intensity of the second largest diffraction intensity. The method of obtaining the above mentioned material involves forming on the carbon substrate, film of tantalum carbide using CVD method and thermal processing at 1600-2400°C. |
|
Method of obtaining of cordierite ceramic pigment Invention relates to obtaining heat-resistant ceramic pigments for colouring ceramic masses and glazes, as well as for obtaining under-glaze and over-glaze ceramic paints. Method consists in the following: charge containing mixture of talc, kaolin and technical alumina, providing stehiometric composition of cordierite, is mixed with solution of chromophore in concentration 4.0-15.6 g-ion/100 g of solution according to volume ratio "mineral powder : chromophore solution" 1:1 - 1:4 and boiled for 30-60 minutes. Then sediment is separated from solution, dried and burned at temperature 1100-1200°C. Boiling of charge ensures more equal distribution of colouring salt throughout the volume of mineral powder mixture before synthesis, which facilitates process of embedding of colouring ions into crystalline structure of cordierite during burning and makes it possible to increase brightness of pigments. Obtained pigments have bright-blue, beige, sand, green, red-brown colour. |
|
|
Method of making conglomerate engobe Any type of clay can be used when making conglomerate angobes, provided it can dissolve in natrium liquid glass. The clay is unfurled in water with natrium liquid glass up to 50-70% moisture. The quantity of liquid natrium glass added to the unfurled clay is equal to the quantity necessary for maximum dissolution of the watery ceramic slip with 40-45% moisture of the same clay. The unfurled clay is settled until it fully separates into sediments and a sedimental-stable suspension of clay minerals. The obtained water suspension of clay minerals, Particles of which are mot more than 1 mcm in size, are taken to the surface of the formed dry clay products, dried and are burnt in an acidic medium at temperature of 900-1050°C. An engobe-gloss coating with low water absorption capacity is obtained on the surface of the product. |
|
|
Proposed engobe contains high-fusing clay, iron ore and additionally it contains water glass at the following ratio of components, mass-%: high-fusing clay, 90-93; iron ore, 2-3; water glass, 5-7. |
|
|
Method of surface and volume protection of ceramic matrix c/sic and sic/sic-type composites Invention relates to technology of applying coatings to provide surface and volume protection of ceramic matrix C/SiC and SiC/SiC-type composites against oxidation at elevated operation temperatures of articles. Method comprises saturation of composite material with oxides of refractory group IV elements (Ti, Zr, Hf, Th, U), drying, and subsequent treatment of composite with aqueous or organic solutions or sols of group III metals followed by heat treatment. Refractory group IV oxides and actinide oxides are deposited onto composite from 30-50 wt % water-organic suspension of fractioned nanocrystalline micropowders having spherical particle size 0.8-1.5 μm and composed of nanoparticles 20-150 nm in size. Drying is performed at 150-300°C. Aqueous and organic solutions and sols are prepared from group III metal (Al, Sc, Y, all lanthanides) salts or complex compounds. Final heat treatment is performed at 900-1000°C, after which protective glassy layer is deposited. |
|
Molded ceramic article with photo-catalytic coat and method of manufacture of such article Ceramic article is characterized by porous oxido-ceramic coat which is photocatalytically active and contains TiO2; its specific surface ranges from 25 m2/g to 200 m2/g. TiO2 is obtained by flame hydrolysis of TiCl4 in form of highly dispersed powder. Thickness of layer of coat ranges from 50 nm to 50 mcm. Layer with cambers may be located between surface of material of base and photocatalytically active coat. It is preferably to have superhydrophobic surface of coat. Method of making such molded ceramic article includes preparation of suspension of photocatalytically active oxido-ceramic powder, application of this suspension on base and hardening of layer thus obtained by means of drying or roasting. For obtaining superhydrophobic surface, polysiloxane solution is added to starting suspension. |
|
|
Method of application of protective coats on articles made from carbon graphite materials (versions) Proposed coat is used for articles working in atmosphere of silicon or germanium vapor. Proposed method includes application of protective coat on articles made from carbon graphite materials; protective coat contains the following components, mass-%: silicon nitride ground to fractions of 200 mcm, 30-85; binder at viscosity of 10-300 stokes diluted to required consistency, 15-70. Binder contains mixture of 40-60-% solution including 70-75% of phenol formaldehyde resin, 18-22% of dichloropropanol and 5-10% of benzyl and/or isopropyl alcohol, 40-60% of powder containing 90-95% of finely dispersed graphite and 5-10% of para-toluene- sulfochloride and/or toluene sulfonic acid. Then, article is dried in drying cabinet first at temperature of 60-70 C for 20-30 minutes and then at temperature of 230-260 C for 40-60 minutes, after which article is cooled in atmosphere. According to second version, prior to application of protective coat, article is impregnated with aqueous solution of saccharose at content of sugar of 40-80% for 5-10 minutes. According to third version, article is subjected to preliminary impregnation in suspension containing 20-30% of solution by weight containing 70-75% of phenol formaldehyde resin, 18-22% of dichloropropanol and 5-10% of benzyl and/or isopropyl alcohol, 25-30% of finely dispersed graphite powder at addition of 5-10% of para-toluene-sulfochloride and/or toluene sulfonic acid and 40-50% of ethanol. |
|
|
Molded ceramic article with photocatalytic coat and method of manufacture of such article Molded article has porous photocatalytic active coat which contains TiO2 or Al2O3 (aluminum oxide C) in combination with other oxides of metals, for example SiO2; its specific surface ranges from about 25 m2/g to about 200 m2/g. Average diameter of pores or capillaries of articles ranges from 0.1 to 5 mcm. At least one bossy layer may be placed in between oxidoceramic material of base and photocatalytic active coat. Surface of article may be waterproofed. Method of manufacture of article includes preparation of suspension of photocatalytically active material, application of this suspension on article for forming the required layer and hardening of this layer. |
|
|
Method of production of composite material Proposed material possesses high erosion resistance and high-temperature strength at working temperatures of 1000-1700C. Method of production of composite material includes impregnation of ceramic fiber blank with inorganic sol, molding and dehydration of blank by deformation followed by drying at temperature of 50-80C continued for 1-3 h. Dried blank is additionally subjected to impregnation with silicon organic polymer containing nano-powder SiC and secondary drying at temperature of 100-150C continued for 1-3 h. Content of nano-powder SiC in silicon organic polymer is equal to 1-5 mass-%. Heat treatment of blank is performed at temperature of 700-800C for 3-5 h. |
|
Porous aluminum-wetting ceramic material Claimed material contains open-porous or gauze ceramic structure, wherein surface of said structure under using is exposed by melted aluminum and wetted therewith. Structure is made of ceramic material which is inert and resistant to melted aluminum such as alumina, and aluminum-wetted material including metal oxide and/or partially oxidized metal such as manganese, cobalt, nickel, copper or zinc, which is capable to interact with melted aluminum to produce surface layer, containing alumina, aluminum and metal, obtained from metal oxide and/or partially oxidized metal. Ceramic structure includes coating from aluminum-wetted material carried on inert and resistant material or comprises mixture of inert and resistant material and aluminum-wetted ceramic material. |
|
Ceramic filter element manufacturing process Invention relates to manufacturing filter element suited to filter pulps and effluents from galvanic shops. Preliminarily, magnesium montmorillonite cake is prepared at temperatures sufficient to remove gas-forming components, which cake is then ground to particle size not less than pore size in permeable surface of substrate. Mix is further prepared from naturally occurring magnesium montmorillonite and cake, content of the latter in mix being within a range of 30 to 70%. Thereafter, aqueous suspension is prepared comprising uniform fused corundum and above mix in solid phase. This suspension is used to deposit membrane material components. Subsequent heat treatment is conducted with isothermal exposure periods at temperatures sufficient to remove physically adsorbed and crystallization moisture, to cause residual gas emission, and melting of fusible components of membrane layer. Cooling to 400°C is conducted under forced air circulation conditions and, below 400°C, under natural heat convection conditions. |
|
Proposed method includes application of slip on contact surface; slip contains 50-70 mass-% of aluminum oxide powder Al2O3 and 30-50 mass-% of binder which contains 50-60 mass-% of aluminum chloride AlCl3 dissolved in 40-50 mass-% of water. Then reservoir is dried and roasted in oxidizing atmosphere at temperature of 1450-15500°C for at least 20 min. In some cases, use is made of slip containing water-soluble organic dye. Used as organic dye is methylene blue at total content of 0.1-0.5 mass-%. Specification gives description of slip used for passivation of contact surface of refractory reservoir. Proposed method makes it possible to form absolutely inert coat on contact surfaces of ceramic reservoirs relative to alloys of titanium coat. |
|
|
The invention is pertaining to the field building industry; production of ceramic building materials, for example, it may be used in production of the color ceramic bricks applied for an external lining of buildings, facilities and formation of interiors. The engobe for a facing ceramic bricks contains in its composition (in mass %): a wollastonite concentrate - 31-35, a colorless transparent glassbats - 35-40, burnt gault or burnt clear gault - the rest. The engobe is prepared using a slip process by a wet grist in a ball mill. The acicular form of wollastonite crystals provides a good hiding of an angobe coating, and in a combination with glass bats - an adhesive strength of the coating. Blockading of the open pores on the face surface of an item due to a densely sintered angobe layer results in a decrease of the general hydraulic conductivity of the items and at a sufficient cohesive strength of a decorative layer with the ceramic basis improves frost resistance of the decorated lining ceramics. The high chemical purity of the wollastonite concentrate and utilization of colorless transparent glass bats (with the contents of staining oxides of no more than 0.20 %) increases the coating whiteness and improve the decorative properties of the angobed items. The necessary color palette of the coating depends on the choice of a ceramic pigment. The technical problem of the invention is to increase the strength of adhesion with the ceramic base, to improve whiteness and frost resistance of the items. |
|
Invention relates to coatings to protect parts of exhaust system of gliders made from heat-resistant alloys and corrosion-resistant steels against high-temperature gas corrosion under operation at temperatures up to 600°C. Coating contains, wt %: SiO2 20.0-36.5, B2O3 4.0-5.0, Al2O3 5.0-6.0, BaO 5.0-6.0, CaO 2.0-4.0, MgO 0.5-1.5, TiO2 1.5-2.5, Cr2O3 15.0-17.0, Na2O 0.6-0.7, P2O5 0.5-1.5, sodium liquid glass 23.0-27.0, and mineral silica-based complex compound 5.0-6.0 composed of, wt %: SiO2 56.25-58.05, Al2O3 34.3-35.1, CaO 1.0-1.2, MgO 1.0-1.1, K2O 2.5-2.6, Na2O 0.6-0.7, TiO2 1.6-1.8, SO3 0.15-0.25, Fe2O3 0.8-1.0, or, instead of SiO2 56.25-58.05, SiO2 35.25-40.05 and SiB4 18.0-21.0. Reliability of operation with thus coated parts is increased by a factor of 1.5-2. |
|
Invention is related to aircraft industry and intended to use for protection of nonmetallic materials based on silicon carbide matrix and carbon fiber filler against oxidation. High-temperature coating is composed of, wt %: silicon 4-6, boron 2-4m hafnium oxide 60-65, hafnium boride 6-10 and, additionally, hafnium silicides 7-10 and silicon boride 2-4. Resulting carbon-silicon composites are resistant to temperature 2000°C. |
|
|
Thermostatic coating composition Claimed composition contains (mass %): potassium metasilicate with module of at least 4.5 and density of 1.185-1.195 g/ml 24-30; distillated water 23-37; and modified zirconium(IV) oxide of high purity as a pigment. Coating composition of present invention is useful in passive thermostatic systems for spacecrafts. |
Another patent 2513923.