52results about How to "Firing shrinkage is small" patented technology

The invention relates to an alumina-based ceramic core for directional solidification and a preparation method thereof. The refractory materials used in the alumina-based ceramic core include 65-95% of EC95 fused mullite, 5-30% of zirconium silicate, 2-8% of silica powder, 1-5% of titania powder and 1-10% of aluminium powder by weight percent, wherein EC95 fused mullite, F200 powder accounts for 10-30%, F320 powder accounts for 40-70% and F600 powder accounts for 10-30%. The preparation method is characterized by comprising the following steps: ball-milling the above powders and mixing the powder uniformly, putting the mixture into a molten plasticizer to be mixed, forming on a ceramic core forming machine through hot pressing, finishing a ceramic core formed through hot pressing and correcting the shape of the ceramic core, roasting in a box-type resistance furnace, and adopting a high-temperature reinforcer and a room-temperature reinforcer to respectively carry out high-temperature reinforcement and room-temperature reinforcement on the ceramic core discharged from the furnace. The alumina-based ceramic core prepared by the preparation method has the characteristics of high high-temperature strength, good creep resistance, small firing shrinkage, low firing temperature and good metallurgical and chemical properties.

The invention relates to a blank body of fine porcelain ceramic, a preparation method and an application thereof. The raw materials of the blank body comprise the following components in the percentage by weight: 30-50% of calcined kaolin with high aluminum, low contraction and low thermal expansion, 10-20% of porcelain waste powder, 10-20% of quartz sand and 20-40% of ball clay. The invention also further discloses fine porcelain ceramic and a preparation method thereof. The fine porcelain ceramic can be used for casting a product with the size greater than 1,000 mm, and the product is flat, straight and regular and is not easy to deform.

The invention relates to a gradient porous material and a preparation method thereof, an atomizer and an electronic atomization device. The preparation method of the gradient porous material comprisesthe following steps of: preparing raw materials of all functional layers into corresponding slurry, wherein the slurry of at least two functional layers is prepared from different raw materials; respectively spray-drying the slurry of each functional layer to prepare dry granulation powder of each functional layer; and distributing the dry granulation powder of each functional layer according toa preset gradient structure, carrying out compression molding, and sintering to prepare the gradient porous material with a plurality of functional layers. According to the preparation method of the gradient porous material, the interface bonding force between functional layers is improved.

The invention discloses a preparation method of a honeycomb-shaped Mn-based low-temperature denitration catalyst. The preparation method comprises steps as follows: (1), titanium dioxide, a molecularsieve and a solution containing manganese nitrate, cerium nitrate and iron nitrate are mixed uniformly, a mixture is dried, roasted at low temperature and smashed, and a powdery material is obtained;(2), the powdery material obtained in the step (1) is subjected to a forming process of the denitration catalyst, and the honeycomb-shaped Mn-based low-temperature denitration catalyst is obtained. The catalyst prepared with the method has larger pore volume and higher strength and is good in forming performance and not prone to cracking, the active components are manganese oxides in different valence states, and the catalyst is excellent in denitration performance and has good capability of resisting water vapor and SO2 poisoning.

The invention relates to a low-creep zircon overflowing brick and a preparation method thereof. The low-creep zircon overflowing brick comprises, by mass, 100% of zircon powder, wherein zircon oxide short fibers account for, by mass, 0.0-4.0% of the zircon powder, silicon oxide powder accounts for, by mass, 0.1-2.0% of the zircon powder, and composite additives account for, by mass, 0.1-0.8% of the zircon powder. The composite additives can be La2O3, or CeO2, or combination of La2O3 and Y2O3, or combination of CeO2 and Y2O3, or combination of La2O3, CeO2 and Y2O3. According to the low-creep zircon overflowing brick and the preparation method thereof, strength of green bodies is improved, firing shrinkage of the green bodies is reduced, manufacturing yield of products is improved, bonding strength of crystal boundaries of zircon is enhanced, the high-temperature bend-creep rate of products is effectively lowered, and the service life of super-large-size overflowing bricks is prolonged.

The present invention relates to a mineral bone powder, crystal bone china and a production method of the crystal bone china. The mineral bone powder is synthesized by mineral apatite and dolomite. A crystal bone china green body consists of ingredients in weight percent as follows: 39-46% of mineral bone powder, 25-32% of crystal, 9-15% of potassium feldspar, 12-18% of synthetic clay, 1-5% of nano-activated clay, and 2-6% of spodumene. The production method of the crystal bone china includes the steps of ingredient mixing, molding, biscuiting, glazing and glaze firing; the crystal needs calcination acid treatment; and the product is formed by biscuiting and glaze firing. For the crystal bone china, by reasonable ingredient mixing, mineral bone powder and crystal are adopted as main materials for producing high-grade china, the firing temperature range is wide, the firing control is easy, and the crystal bone china integrates the characteristics of high white degree, good semi-transparency, high mechanical strength and good thermal stability; and the scientific and rational production method which is easy to implement effectively ensures the quality and the qualified rate of the product and is conducive to industrial production.

The invention discloses a preparation method of a stannic oxide ceramic electrode, belonging to the field of a ceramic technology. The method comprises the steps of: by taking nano antimony-doped stannic oxide powder and CuO powder as sintering aids, blending SnO2 powder with the sintering aids; then, adding a dispersing agent and a bonding agent into the mixture obtained from the former step; and carrying out wet grinding, drying, crushing granulation and isostatic compaction and then firing to prepare the stannic oxide ceramic electrode, wherein the mass percent of the SnO2 powder is 83-91% of the ingredients, the mass percent of the nano antimony-doped stannic oxide powder in the sintering aids is 9-17% of the ingredients, and the mass percent of the CuO powder is 0-0.6% of the ingredients. The preparation method is simple in technology and high in product pass rate, and the obtained stannic oxide ceramic electrode is high in density and low in resistivity at the room temperature and the high temperature.

The invention discloses a method for reducing the firing shrinkage coefficient of an alumina ceramic material and product made by the same. The firing shrinkage coefficient of the alumina ceramic material can be reduced by adopting metal aluminum powder instead of aluminum oxide powder so as to reduce the firing deformation rate of the product; the accurate control on size of alumina ceramic product can be implemented, and the post-processing cost of the product can be reduced by controlling the firing shrinkage coefficient to be tiny; the method for reducing the firing shrinkage coefficient of the alumina ceramic material is suitable for industrialized production.

The invention discloses a corundum-silicon carbide crystal whisker composite ceramic material taking natural minerals as raw materials. The corundum-silicon carbide crystal whisker composite ceramic material is prepared from a basic material and a binding agent, wherein the basic material is prepared from the following components: 65 to 90 weight percent of aluminum silicate minerals and 10 to 35weight percent of metal aluminum powder and the dosage of the binding agent is 6 to 12 weight percent of the basic material. Furthermore, the invention discloses a preparation method of the corundum-silicon carbide crystal whisker composite ceramic material taking the natural minerals as the raw materials. A mixture of the natural minerals and the metal aluminum powder is used as a raw material system and corundum and silicon carbide crystal whiskers are introduced through an in-situ synthesis manner, so that the problem in the prior art that industrial powder and aggregate are not easy to mixuniformly is effectively solved and the performance of the corundum-silicon carbide composite ceramic material is improved to the greatest extent. The corundum-silicon carbide crystal whisker composite ceramic material disclosed by the invention has the advantages of easiness for obtaining the raw materials, simple technology, low firing temprature and high rate of finished products; the corundum-silicon carbide crystal whisker composite ceramic material has important meanings of improving the quality of the corundum-silicon carbide composite ceramic material and saving the product cost, andis good for progression and development of popularization and application and an industry technology.

The invention belongs to the field of refractory materials, and provides a method for manufacturing large-size refractory bricks.The method for manufacturing the refractory bricks comprises the steps that spherical pelleting materials are adopted as a matrix, and fine particles with the grain size of 0.1 mm to 1 mm are adopted as aggregate; the spherical pelleting materials, water and a binding agent are manufactured into slurry in a stirrer, and the slurry is manufactured into spherical matrix pelleting materials with the water content of 0.2% to 0.5% through a centrifugal spraying pelletizer; the spherical matrix pelleting materials and the fine particles are subjected to dry blending in mixing equipment, and an even mixture is obtained; the mixture is directly contained in a mold and subjected to pressure forming in an isostatic pressing machine at the pressure of 90 MPa to 180 MPa, and blanks with enough strength are obtained; the formed blanks are dried for 24 h at the temperature of 120 DEG C, then heat preservation is carried out for 6 h to 10 h at the temperature of 1,500 DEG C to 1,650 DEG C, and the large-size refractory bricks can be obtained.The manufactured large-size refractory bricks have the advantages of being even in structure, high in density and strength and good in corrosion resistance.

The invention provides a ceramic railing with high weatherability, and a preparation method thereof. Because of self-factors, when a ceramic railing is used, glaze-surface falling and cracks on parts of the structures can easily occur; under weather conditions with large temperature differences, glaze-surface bursting might occur, and normal application is severely influenced; during a firing procedures, because of uneven air flow, slow heat transfer and low heat exchange efficiency in a kiln, regular and controllable temperature gradient can hardly be formed longitudinally in a firing zone in the kiln, such that the firing period is prolonged. With the method provided by the invention, the technical problem is solved. According to the invention, a raw material formula is modified, and a local clay resource in Yunnan Province is adopted as a raw material. The formulas for a ceramic railing blank and a glaze are further optimized, and a firing process procedure is also modified, such that the weatherability of a finished product is improved. Indexes of performances such as water absorption rate, freezing resistance, quick-chilling resistance, quick-heating resistance and appearancequality of the ceramic railing product satisfy a construction colored glaze product standard JC/T765-2006.

The invention discloses fireproof inorganic quartz stone and a preparation method thereof. According to the preparation method, the raw materials are lightly sintered and sintered, so that a part of physical and chemical reactions of the raw materials can be completed, cremation of ore is realized, lattice defects are increased, sintering is promoted effectively, therefore, the preparation efficiency can be effectively improved; a double-sided hot-pressing mode is adopted for extrusion molding to obtain a green body, so that the green body is compact in structure, high in strength and small indrying and firing shrinkage, the size is easy to control, the layer density phenomenon of the green body can be effectively reduced, the total porosity of the green body is reduced, the fireproof performance can be effectively improved, and the using efficiency is increased; a plurality of times of extrusion is adopted, and extrusion time is prolonged, so that gas in the green body can be effectively and smoothly exhausted, the elasticity of the green body can be effectively improved, the strength of the green body can be effectively improved, the green body can be effectively prevented fromcracking, and the preparation efficiency of the green body can be effectively improved.

The invention relates to a silicon oxide-based ceramic core for a large-size directional hollow blade of a heavy gas turbine and a preparation method of the silicon oxide-based ceramic core. The silicon oxide-based ceramic core adopts quartz glass powder as a base material, and adopts zircon powder, alumina powder and calcium oxide powder as mineralizing agents. The powder comprises the following components in percentage by weight: 60-95% of quartz glass powder, 1-30% of zircon powder, 0.5-5% of alumina powder and 0.1-5% of calcium carbonate powder. Paraffin, beeswax, polyethylene and polyethylene glycol are used as plasticizers for hot-press injection molding. The preparation method comprises the following steps: ball-milling and uniformly mixing the powder materials, putting the powder materials into a molten plasticizer for mixing, and carrying out hot-press injection molding on a ceramic core molding machine. A quartz glass rod/tube is pre-arranged in the position, corresponding to the thick and large section of the mold core, in the mold core mold before pressure injection, and the ceramic mold core formed through hot pressure injection molding is put into a box-type resistance furnace to be roasted after being trimmed and corrected. The silicon oxide-based ceramic core prepared by the invention has the characteristics of high high-temperature strength, good creep resistance, small firing shrinkage, stable size and high core removal efficiency.

The invention discloses a core manufacturing process for investment casting, which includes the following steps: (1) Slurry preparation: put zircon powder and quartz glass in a ball mill for 2-4 hours, take them out and dry them, Make the moisture content lower than 0.2% by mass, and then add a stirrer to stir to obtain a slurry; (2) Forming: forming by hot pressing; (3) Bowl filling: bury the pressed ceramic core body in a container In the bowl of the filler, prevent the core from being deformed and damaged during the firing process; (4) filling filler: use industrial alumina baked at 1300°C for 4‑6h as filler; (5) shape: at an amplitude of 0.2‑0.5mm (6) Roasting: It is divided into two stages: wax removal and sintering. The core produced by this process can obviously improve the anti-deformation ability of the core, and reduce the shrinkage of the core during firing, and obtain High performance and high quality core.

The invention discloses a ceramic floor drain and a preparation method thereof. The ceramic floor drain is prepared from, by mass, 8.0-12.0% of waste porcelain powder, 9.0-11.0% of potassium feldspar,7.0-9.0% of quartz, 1.5-2.5% of alumina, 2.6-3.2% of dolomite, 0.1-1.0% of a surfactant, 10.0-12.0% of paraffin and the balance kaolin. The ceramic floor drain has the advantages of low cost, high strength, high precision, great deformation resistance and the like.