56results about How to "Low linear shrinkage" patented technology

Provided are inorganic fibers containing calcium and alumina as the major fiber components. According to certain embodiments, the inorganic fibers containing calcia and alumina are provided with a coating of a phosphorous containing compound on at least a portion of the fiber surfaces. Also provided are methods of preparing the coated and non-coated inorganic fibers and of thermally insulating articles using thermal insulation comprising the inorganic fibers.

The invention relates to a silicon carbide ramming material high in abrasion resistance, which comprises the following components in part by weight: 55-78 parts of superfine silicon carbides, 5-15 parts of alpha type silicon nitrides, 5-10 parts of zirconium corundum, 1-7 parts of aluminum oxide powder and silicon dioxide powder, 9-13 parts of aluminum chromium phosphates, 0.5-5 parts of coagulation accelerators, 0-2.5 parts of iodine bismuth oxyiodide tannates and 0.3-0.7 parts of anti-explosion fibers, wherein the mixture of active rho-aluminum oxide and magnesium oxide is taken as the coagulation accelerators, and the diameter of the anti-explosion fibers is 1.5-2.5 microns. The silicon carbide ramming material high in abrasion resistance, which is provided by the invention, is high instrength after being naturally dried, is excellent in abrasion resistance at high temperature, is high in heat transfer coefficient, is low in linear contractibility rate and is long in service life.

The invention discloses a low-temperature semiwhite porcelain and a manufacturing method thereof, belonging to the technical field of ceramics. The blank of the low-temperature semiwhite porcelain comprises the following raw materials in parts by mass: 30-40 parts of Longyan clay, 25-35 parts of Gangxi kaolin raw ore, 20-28 parts of flint, 7-12 parts of feldspar, 2-9 parts of talcum and 5-10 parts of dolomite. The low-temperature semiwhite porcelain can be quickly fired at the low temperature of 1000 DEG C, and can be discharged out of the kiln only by 7-8 hours from firing to cooling. The linear shrinkage is low and can be kept at 12% or below. The low-temperature semiwhite porcelain has high hardness and excellent whiteness (85% or above), and has comparable whiteness with light-weight porcelain. The low-temperature semiwhite porcelain has low water absorptivity (which can be kept at 3% or below and can reach the porcelain industry standard), has the advantages of high strength excellent high temperature resistance and excellent microwave resistance, can be subjected to 180-DEG C drying oven testing more than twice, and can pass the microwave oven and dishwasher performance test. The low-temperature semiwhite porcelain has wide applicability, and can be widely used for producing medium/high-grade domestic ceramics.

The invention relates to a three-dimensional freezing printing method of ceramic components. The method comprises the following steps that (1) ceramic powder, silica sol, polyethylene glycol and polyvinyl alcohol are subjected to ball milling to obtain a ceramic slurry; (2) a printing cavity of a 3D printing device is cooled to minus 10 DEG C to minus 60 DEG C, and then the ceramic slurry is usedfor printing; the wet mud material extruded from nozzles is bonded to a printing base plate to form a first layer of mud material; printing is continuously conducted, the wet mud material extruded from the nozzles continuously form a second layer of mud material, a third layer of mud material.., and an Nth layer of mud material on the first layer of mud material; and the formed mud layers are gradually fused, and when printing is carried out to by 4-10 layers, the inner mud material layers and the interlayers are gradually frozen and solidified to obtain a green body; and (3) the green body isfreeze-dried and then heated and sintered to obtain the ceramic component. According to the printing method, the integrity of the printed ceramic can be realized, and the bonding strength between thelayers is improved.

The invention discloses polybenzoxazine aerogel and a preparation method thereof, and belongs to the technical field of aerogel materials. The preparation method comprises the steps of: dissolving a benzoxazine monomer in an organic solvent to obtain a benzoxazine monomer solution; adding an aliphatic polyamine cross-linking agent, mixing well, pouring the solution into a mold, heating for a gelation reaction, and aging to obtain polybenzoxazine wet gel; then carrying out normal pressure drying to obtain polybenzoxazine aerogel with a low reaction degree; and heating to 200 DEG C in air in a stepped manner, preserving heat for 2-12 hours at each temperature section, and cooling to room temperature to obtain polybenzoxazine aerogel. The linear shrinkage rate of the aerogel can be reduced, and the aerogel is good in thermal stability and easy to form.

The invention discloses a high-heat-dissipation air-ventilation tray type cable bridge, and relates to the technical field of cable bridges. The high-heat-dissipation air-ventilation tray type cable bridge comprises a bridge bottom plate and bridge side plates arranged on the two sides of the bridge bottom plate, wherein the bridge bottom plate is composed of a plate body I, a plate body II, a plate body III and a plate body IV in a spliced manner, wherein the plate body I comprises a side edge I and a side edge II which are opposite to each other; the plate body II comprises a side edge III and a side edge IV which are opposite to each other; the plate body III comprises a side edge V and a side edge VI which are opposite to each other; the plate body IV comprises a side edge VII and a side edge VIII which are opposite to each other; the side edge I is fixedly connected with the bridge side plate; the side edge II is hinged to the side edge III; the side edge IV is hinged to the sideedge V; the side edge VI is hinged to the side edge VII; the side edge VIII is fixedly connected with the other bridge side plate. The invention further discloses a preparation method of the high-heat-dissipation air-ventilation tray type cable bridge. The width of the bridge can be adjusted according to needs, the cables can be placed in a classified mode, and meanwhile, the bridge has high heatdissipation performance.

The invention relates to the technical field of preparation of mortar, and particularly discloses micro-expanded fireproof heat-insulating mortar and a preparation method thereof. The micro-expanded fireproof heat-insulating mortar contains the following components in parts by weight: 100-150 parts of cement, 150-300 parts of quartz sand, 20-40 parts of heavy calcium powder, 10-20 parts of redispersible powder and 50-80 parts of functional material; the functional material contains the following components in parts by weight: 30-50 parts of glass bead, 30-50 parts of vermiculite, 10-20 parts of lignin and 5-10 parts of graphite powder. All the components are selected from non-toxic components, thus being environment-friendly and pollution-free; the prepared micro-expanded fireproof heat-insulating mortar can be prevented from generating cracks due to shrinkage in drying, and has excellent anti-cracking property; in addition, the micro-expanded fireproof heat-insulating mortar is good in heat-insulating property, and high in strength and flame-retardant degree.

The invention discloses a preparation method of a porous high-strength mullite refractory raw material and belongs to the technical field of refractory raw materials. The preparation method comprisesthe specific steps that raw bauxite and a pore-forming agent are used as raw materials, water accounting for 10-40wt% of the raw materials is added, mixed grinding is carried out for even mixing, thenforming is carried out, and thus a refractory raw material green body is obtained; the green body is baked in an electrothermal blowing drying box with a baking condition of 110 DEG C for 24 hours, then the dried green body is put into a sintering furnace, the temperature is kept at 1,550 DEG C for 3 hours, heating is carried out with the heating rate of 3 DEG C.min<-1>, in-situ reaction sintering is carried out at high temperature, and thus a mullite crystal is generated; and the sintered mullite crystal is taken out of the furnace, cooled and then subjected to graded crushing, and thus theporous high-strength mullite refractory raw material is obtained. The preparation method has the advantages that the prepared porous high-strength mullite refractory raw material is small in pore size, even in pore diameter distribution, small in volume density, low in thermal conductivity, good in thermal stability, low in linear shrinkage rate and high in compression strength.

The invention discloses a method for preparing a ceramic brick by using fly ash. The method comprises: 1) adding high-calcium fly ash to a 40-150 g/L soluble alkali solution system, and carrying out a reaction; 2) filtering the slurry obtained after the reaction in the step 1), and washing, wherein the obtained filtration residue is surface modified high-calcium fly ash; 3) grinding the surface modified high-calcium fly ash, clay and a flux raw material; 4) granulating; 5) molding the spherical powder obtained in the step 4), and drying to obtain a ceramic brick billet; and 6) heating the ceramic brick billet, carrying out thermal insulation, and cooling to prepare the ceramic brick. The ceramic brick of the present invention has the low temperature firing characteristic.

The invention discloses a low-shrinkage blended wax material and a preparation method thereof, and relates to the technical field of precision investment casting. The preparation method comprises the steps: heating and melting rosin and paraffin, adding a grain refiner, a viscosity modifier, a flexibilizer and a heat stabilizer into liquid wax, placing in a reaction kettle, and uniformly mixing to prepare the novel reusable special blended wax. The special novel blended wax has the advantages of small linear shrinkage rate, small expansion coefficient within softening temperature, low heat capacity, sufficient strength and hardness, small viscosity in a molten state, small residual ash content, low content of low-temperature volatile matters, good chemical stability, fine grain structure, repeated use and the like. The prepared special novel blended wax can meet the size precision requirements and surface quality requirements of various complex precision castings and has wide market application prospects, and meanwhile, the preparation method is simple, low in cost, high in applicability, capable of being repeatedly used and capable of being used for large-scale production.

The invention discloses a magnesium-zirconium spinel ramming material for a furnace bottom. The ramming material is prepared from the following raw materials in parts by weight: 50-80 parts of high-grade magnesia, 10-35 parts of magnesium aluminate spinel, 2-8 parts of zirconium oxide and 7-15 parts of carbon-contained binding agent. The ramming material can be used for improving the filling condition of a triangle area part at the furnace bottom and providing a certain protection for a furnace shell in a high-temperature state, so that the furnace life is prolonged, and the working safety is favorably realized.

The invention provides a filling type investment casting pattern material with high filler content. The filling type investment casting pattern material comprises the following components in percentage by weight: 20%-50% of petroleum wax, 10%-40% of tackifying resin, 5%-10% of vegetable wax, 0%-5% of a high-molecular polymer, 30%-50% of a solid filler and 0%-8% of a dispersing agent. The prepared investment casting pattern material is high in solid filler content, small in linear shrinkage rate, high in size precision and good in processing property.

The invention belongs to the technical field of precision casting, and particularly relates to a precision casting modulated wax. The precision casting modulated wax comprises the following raw materials of, in parts by mass, 44 to 46 parts of microcrystalline wax, 2.5 to 3.5 parts of candelilla wax, 34 to 36 parts of carnauba wax, 3.5 to 4.5 parts of ethylene-vinyl acetate copolymer, and 12 to 14parts of pure monomer resin. The modulated wax is applied to the precision casting industry, and has the characteristics of strong stability, high strength and difficulty in deformation, low gray scale and reduced pollution to metal casting, easy demolding and easy to melt and flow out of a shell with a wax mold when demoulding, and being capable of effectively improving the production efficiencyin the precision casting process.

The invention relates to the technical field of aluminum alloy materials, and discloses a high-yield-strength aluminum alloy and a preparation method thereof.The high-yield-strength aluminum alloy comprises, by mass, 9.5%-12% of silicon, 0.5%-0.8% of manganese, 0.1%-0.6% of magnesium, smaller than or equal to 0.15% of iron, smaller than or equal to 0.12% of titanium, 0.02%-0.04% of strontium, 0.1%-0.2% of lanthanum-cerium mixture (the ratio of lanthanum to cerium is 7: 3) and the balance aluminum and inevitable impurities, and the total amount of the impurities is smaller than or equal to 0.1%. According to the scheme, by increasing the silicon content, the wear resistance of the aluminum alloy is improved while the hardness of the aluminum alloy is guaranteed; and meanwhile, different types of rare earth elements are added, alloy components and structures are optimized, harmful impurity elements are purified through the rare earth, grains are refined, the purpose of refined grain strengthening is achieved, and therefore the yield strength and wear resistance of the aluminum alloy are improved.

The invention discloses a method for determining a lime mixing amount ratio in expansive soil, relates to the technical field of civil engineering, and aims at solving the problems that in the relatedart, the expansive soil is improved through the lime, and after lime metering exceeds a certain value, the mechanical index and the water stability of the lime stabilized soil are reduced, and the method comprises the following steps that S1, taking the expansive soil and the lime; S2, preparing an EDTA standard titer line according to the water content controlled by construction; S3, taking 3-6%of lime, and uniformly mixing with the lime to obtain a mixed soil sample; S4, culturing bacillus megaterium liquid and preparing cementing liquid; S5, adding diluted 60-80% bacillus megaterium liquid into the mixed soil sample, uniformly stirring, and standing for 2 hours; S6, after 2 hours, sucking out the bacillus megatherium liquid, adding 60-80% of cementing liquid, continuing to solidify, uniformly stirring, and standing for 22 hours; and S7, sucking out the bacillus megaterium liquid and the cementing liquid, and repeating the steps S4 and S5 seven times.