49 results about "Aluminum Oxide Paste" patented technology

The invention belongs to the field of functional composite materials, and particularly relates to low-viscosity and high-dispersity aluminum oxide slurry and a preparation method thereof.The low-viscosity and high-dispersity aluminum oxide slurry is prepared from a newly-designed phosphono-carboxyl block copolymer and biquaternary ammonium salt polyether silane as composite modifiers; and efficient anchoring and stable dispersion of the surfaces of alumina particles are realized through the synergistic effect of molecular structures. The phosphono-carboxyl block copolymer is prepared through controllable polymerization and deprotection reaction, and strong chemical bonding is formed between a phosphono group and the surface of aluminum oxide; the biquaternary ammonium salt polyether silane is subjected to click chemical synthesis, and electrostatic adsorption of quaternary ammonium salt and the steric hindrance effect of a polyether chain are combined. When the slurry is prepared, the two modifiers are sequentially added into water, the aluminum oxide powder is added after the pH value is adjusted, finally, the isobutylene maleic anhydride copolymer and the defoaming agent are introduced, and the slurry is obtained through vacuum defoaming and filtering. The slurry prepared by the method has the characteristics of high solid content, low viscosity and good dispersion stability.

The invention discloses a preparation method of high-purity alumina electrostatic chuck ceramic, which belongs to the technical field of electrostatic chucks, and comprises the following steps: a) ball milling: mixing high-purity alumina powder with an organic binder, a dispersant and a solvent, and carrying out ball milling treatment; b) tape casting: spreading the aluminum oxide slurry on a tape casting machine through a tape casting process to form a ceramic film, and forming an aluminum oxide ceramic green body; c) preparing an electrode: preparing an electrode layer arranged in the ceramic; d) punching: reserving electrode through holes and holes required by other designs on the formed aluminum oxide ceramic body; e) laminating: laminating a plurality of layers of ceramic films to form a ceramic green body; f) glue discharging: placing the laminated ceramic green body in a glue discharging furnace for heating treatment; g) sintering: performing high-temperature sintering on the degummed ceramic green body; h) leveling: carrying out leveling treatment on the sintered ceramic to enable the surface of the ceramic to be flat; and i) hot isostatic pressing treatment: placing the leveled ceramic main body in hot isostatic pressing equipment.

The invention provides porous biological ceramic as well as a preparation method and application thereof. The preparation method comprises the following steps: mixing aluminum oxide slurry with a pore forming agent to obtain mixed slurry; carrying out light curing reaction on the mixed slurry in a layer-by-layer projection manner by adopting DLP 3D printing, and carrying out layer-by-layer printing, accumulation and forming to obtain a ceramic body; according to the preparation method, through the aluminum oxide slurry composite pore-forming agent and the DLP 3D printing technology, it is guaranteed that no through hole exists in the material, high density and mechanical strength are maintained, and the problem that in the prior art, surface performance and mechanical performance are difficult to consider at the same time is solved; a discrete porous structure is constructed on the surface of the high-solid-content aluminum oxide ceramic, so that accurate regulation and control of the surface roughness are realized, surface discrete holes are directly formed, and a complex post-treatment process is omitted; through the sintering process, the overall sintering shrinkage rate is controlled, the forming precision of a complex structure is improved, the large-scale production requirement is met, and the material can be applied to bone tissue engineering scaffolds and tooth restoration materials.

The invention discloses aluminum oxide ceramic granulation powder and a preparation method thereof and high-density aluminum oxide ceramic, and the method comprises the following steps: weighing required raw materials for later use according to the mass percentage: 75% of aluminum oxide raw powder and the balance of pure water; aluminum oxide grinding balls are put into a ball-milling tank, the weighed aluminum oxide raw powder and pure water are put into the ball-milling tank in the sequence of water first and powder second for ball-milling, the ball-milling time is 3 h, and the rotating speed of the ball-milling tank is 35 Hz; sieving a mixture of the grinding balls and the slurry in the ball-milling tank by using a screen to separate the grinding balls and the slurry; pouring the sieved slurry into a stirring kettle for stirring, sequentially adding a dispersing agent, a binder, a plasticizer and a lubricant in stages in the stirring process, and adjusting the pH value of the slurry to obtain aluminum oxide slurry; and carrying out spray granulation on the aluminum oxide slurry by using a spray granulator to obtain the aluminum oxide ceramic granulation powder. The alumina ceramic granulation powder prepared by the invention is relatively high in apparent density and good in fluidity, and the alumina ceramic sintered by the alumina ceramic granulation powder is relatively high in density.

The invention discloses a stirring device for alumina slurry, which relates to the technical field of stirring devices and comprises a tank body, an upper crossbeam and a rotating shaft one. Lifting cylinders are fixedly arranged on both sides of the rotating shaft one, a rotating shaft two is rotatably arranged in the lifting cylinder, a plurality of propellers are fixedly arranged on the rotating shaft two, a liquid outlet is provided on one side wall of the lifting cylinder, a chute is provided on one side of the liquid outlet, a baffle for blocking the liquid outlet is slidably arranged in the chute, a floating ball is fixedly arranged on one side of the baffle, when slurry is contained in the tank body, the height of the baffle can be controlled by the floating ball floating on the slurry liquid surface, and the slurry in the lifting cylinder can flow out through the liquid outlet located above the baffle, and the sediment at the bottom of the tank body can be sucked into the lifting cylinder and then discharged through the liquid outlet by the rotation of the propeller, and the height of the baffle can be controlled by the floating ball, so that the slurry flowing out of the liquid outlet can always be discharged to the liquid surface.

The invention discloses polishing powder for an automobile paint surface and a preparation method of the polishing powder. The preparation method comprises the following steps: preparing a mixed solution; preparing a roasting material from the mixed solution and pseudo-boehmite, wherein the specific surface area of the roasting material is 30-60m < 2 > / g; grinding the roasted material to obtain aluminum oxide slurry; adding a coupling agent and a dispersing agent into the aluminum oxide slurry, and reacting under a stirring condition to prepare mixed slurry; and carrying out post-treatment on the mixed slurry to obtain the polishing powder of which the particle size distribution D50 is in a range of 0.6-0.9 mu m and the particle size distribution D100 is less than 10 mu m. According to the preparation method of the polishing powder, the prepared polishing powder has good polishing performance, the surface smoothness of a polished automobile paint surface is improved, the polishing powder is easy to store and transport, and the production cost can be effectively reduced.

The invention provides a high-temperature-resistant and low-water-absorption lithium battery diaphragm and a preparation method thereof. The diaphragm is prepared by coating double surfaces or single surface of a base membrane with coating slurry, wherein the coating slurry is mainly prepared by mixing nano calcium stearate and aluminum oxide in a mass ratio of (25-38): (40-55). According to the preparation method, the surface of the base membrane is coated with a layer of aluminum oxide slurry treated by a special process, and meanwhile, the heat resistance of the diaphragm is remarkably enhanced by optimizing the raw material ratio of the coating slurry and the process flow. The coating slurry not only endows the diaphragm with excellent hydrophobic characteristics and effectively reduces the absorption of moisture, but also can maintain extremely low moisture content under extreme environmental conditions, thereby ensuring that the moisture content of the diaphragm is continuously in a low-level state. The innovative method provides a new technical approach for improving the performance of the lithium ion battery diaphragm.

The invention discloses an aluminum oxide waterproof heat-insulating coating as well as a preparation method and application thereof, relates to the technical field of coating materials, and solves the problem that an existing protective coating material cannot meet the requirements of a high-precision chip on interface bonding strength and thermal mechanical stability of a densified coating. The coating comprises loose and porous aluminum oxide slurry A and relatively dense aluminum oxide slurry B, the aluminum oxide slurry A is printed on the surface of the chip blank through the printing process and dried, and the aluminum oxide slurry A is a first layer sintered at high temperature; printing the aluminum oxide slurry B on the surface of the chip blank with the aluminum oxide coating A, and drying, wherein the aluminum oxide slurry B is a second layer of low-temperature sintering; the method can be applied to protection of the zirconia ceramic chip in the nitrogen-oxygen sensor, and has a wide application prospect.

The invention belongs to the technical field of aluminum oxide production, and particularly provides a leaf filter for filtering aluminum oxide slurry and a control method thereof.The method comprises the steps that a flocculating agent is added into the aluminum oxide slurry, the temperature of the aluminum oxide slurry is adjusted to a preset temperature interval, and the pH value of the aluminum oxide slurry is adjusted to a preset pH value interval; determining the viscosity and the suspended matter content of the aluminum oxide slurry, and adjusting the filtering parameters of the leaf filter based on the viscosity and the suspended matter content so as to filter the aluminum oxide slurry; in the aluminum oxide slurry filtering process, a pulse type backwashing device in the leaf filter is started to wash a composite filtering medium in the leaf filter every first time interval; and in the first time interval, based on the inlet pressure, the outlet pressure and the outlet filtrate flow of a filter chamber in the leaf filter, judging whether to start a pulse type backwashing device to wash the composite filter medium or not. According to the technical scheme provided by the invention, the stability of the leaf filter for filtering the aluminum oxide slurry can be improved.

This invention provides a multilayer coated low-temperature carbon capture material, its preparation method, and its application. The preparation method employs a four-layer sandwich multilayer coating process: a mixed slurry-alumina slurry-mixed slurry-alumina slurry. A mixed slurry coating (active layer), an alumina slurry coating (bonding transition layer), a mixed slurry (active layer), and an alumina slurry (protective layer) are sequentially formed on the surface of a porous honeycomb carrier. The transition layer and protective layer formed by the alumina slurry enhance the bonding strength between the active ingredient (potassium carbonate) and the carrier, while preventing the active ingredient from directly contacting external moisture, reducing potassium carbonate shedding during cycling, and ensuring stable carbon capture performance during multiple adsorption-desorption cycles. The multilayer thin-coating method ensures the effective loading of the active ingredient and avoids cracking and peeling caused by excessive internal stress in thick coatings, thus improving the overall stability of the coating.

There is provided a method for producing a coated substrate, the method comprising: forming an aluminium (oxy) hydroxide slurry by simultaneously feeding streams of an aluminium nitrate solution and a basic solution, such as an ammonia solution, into a liquid over a reaction period, while maintaining an elevated temperature and a controlled pH; allowing a substrate to contact the slurry to thereby form an aluminium (oxy) hydroxide coating on the substrate; separating the coated substrate from the liquid.

The utility model provides an aluminum hydroxide slurry grading device which comprises a base, a swirler and an electric rotary table, supporting plates are fixedly installed on the two sides of the top of the base, and a fixing plate is jointly installed on the tops of the two supporting plates. Compared with the prior art, the aluminum hydroxide slurry defoaming device has the following beneficial effects that aluminum hydroxide slurry is conveyed into the electric heating copper pipe through the liquid inlet pipe, the electric heating copper pipe is started to heat and defoam the slurry, and the heated and defoamed slurry is uniformly conveyed into the liquid conveying pipes through the bent pipes; due to the fact that the end, located in the swirler, of each liquid conveying pipe is in the bent shape, and the end opening faces the inner wall of the swirler, when the slurry is conveyed into the swirler, the slurry can flow along the inner wall of the swirler, a large number of bubbles cannot be generated, and the phenomenon that particles in the slurry are wrapped by the bubbles, and consequently the slurry particles are separated unevenly is reduced; and the grading effect of the aluminum hydroxide slurry is effectively improved.

The invention provides a high-dispersion noble metal catalyst and a preparation method and application thereof. The high-dispersion noble metal catalyst is prepared from aluminum oxide slurry, the concentration of aluminum oxide in the aluminum oxide slurry is 25-35 wt%, the particle size of the aluminum oxide in the aluminum oxide slurry is 0.5-20 microns, the D50 of the aluminum oxide in the aluminum oxide slurry is 4-6 microns, and the D90 of the aluminum oxide in the aluminum oxide slurry is smaller than or equal to 10 microns; the aluminum oxide is gamma aluminum oxide, and a solution in the aluminum oxide slurry is water. In the preparation process of the noble metal catalyst, the dispersity of the noble metal is remarkably improved, sintering of the alumina carrier and agglomeration of the noble metal are reduced, and the activity and thermal stability of the catalyst are improved. Meanwhile, the consistency of the product is improved through particle size regulation and control in the preparation process, and the method has a good industrial application prospect.

The invention relates to the technical field of preparation of micro-nano robots, in particular to a preparation method of a drawing pin micro-nano robot. Comprising the following steps: S1, obtaining a porous polycarbonate (PC) template; s2, argon is ionized through a magnetron sputtering deposition system, the silver target is bombarded by ions under the action of an electric field, and silver atoms are sputtered to the back face of the porous polycarbonate template; s3, adhering a double-conductive copper foil adhesive tape to one surface of the porous polycarbonate template with silver to ensure that the double-conductive copper foil adhesive tape is in good electric contact with the silver surface of the porous polycarbonate template subsequently; s4, the drawing pin micro-nano robot is obtained through an electrochemical deposition method; s5, the template is taken down from the electrochemical deposition device, the surface of the template is washed with deionized water, and the electrolyte is removed; s6, polishing the silver surface of the polycarbonate template by using aluminum oxide slurry, removing a silver layer on the surface, and putting the template into a centrifugal tube; and S7, the drawing pin micro-nano robot is centrifugally collected. The problem that a tubular micro-nano robot is single in structure is solved.

The present invention relates to the technical field of micro-nanorobot preparation, and more specifically, to a method for preparing a thumbtack micro-nanorobot. The method comprises the following steps: S1: obtaining a porous polycarbonate (PC) template; S2: using a magnetron sputtering deposition system to ionize argon gas and bombard a silver target with the ions under the action of an electric field, sputtering silver atoms onto the reverse side of the porous PC template; S3: attaching a double-conducting copper foil tape to one side of the porous PC template bearing silver, ensuring subsequent good electrical contact with the silver surface of the porous PC template; S4: obtaining a thumbtack micro-nanorobot using electrochemical deposition; S5: removing the template from the electrochemical deposition apparatus, rinsing the template surface with deionized water, and removing the electrolyte; S6: polishing the silver surface of the PC template with alumina slurry to remove the surface silver layer, and placing the template in a centrifuge tube; and S7: collecting the thumbtack micro-nanorobot by centrifugation. This method solves the problem of the single structure of tubular micro-nanorobots.

The invention discloses a stirring device for aluminum oxide slurry, and relates to the technical field of stirring devices.The stirring device comprises a tank body, an upper cross beam and a first rotating shaft, lifting cylinders are fixedly arranged on the two sides of the first rotating shaft, a second rotating shaft is rotationally arranged in each lifting cylinder, a plurality of propellers are fixedly arranged on each second rotating shaft, and a liquid outlet is formed in one side wall of each lifting cylinder; a sliding groove is formed in one side of the liquid outlet, a baffle used for blocking the liquid outlet is arranged in the sliding groove in a sliding mode, a floating ball is fixedly arranged on one side of the baffle, when slurry is contained in the groove body, the height of the baffle can be controlled through floating of the floating ball on the liquid level of the slurry, and the slurry in the lifting cylinder can flow out through the liquid outlet located above the baffle. Sediments at the bottom of the tank body can be sucked into the lifting cylinder through rotation of the propeller and then discharged through the liquid outlet, the height of the baffle can be controlled through the floating ball, and therefore slurry flowing out of the liquid outlet can be discharged to the liquid level all the time.

The invention discloses diamond reinforced alumina slurry suitable for DLP printing and a preparation method thereof.The slurry is grafted with modified diamond particles through a coupling agent and a polymer, polar groups such as hydroxyl groups and epoxy groups are introduced to the surfaces of the diamond particles through hydrolysis and combination reactions, and the interface bonding force with alumina particles is enhanced; the problem of interfacial compatibility of diamond particles and aluminum oxide is solved, uniform dispersion of the particles and resin is ensured by adopting a three-step composite dispersion process, namely a ball milling-vacuum stirring composite dispersion process, the overall uniformity of the diamond-enhanced aluminum oxide slurry is ensured by adopting a vacuum homogenizer, and the obtained slurry is moderate in viscosity, high in light curing speed and high in strength. The printed and formed ceramic part has excellent mechanical property and wear resistance after being sintered, and is suitable for rapid manufacturing of high-precision complex ceramic parts.

This invention discloses a method for preparing high-purity ceramic sheets for electrostatic chucks, belonging to the field of electrostatic chuck technology, including the following steps: Step S1: Preparing high-purity alumina slurry by mixing and grinding high-purity alumina micro powder, composite organic carrier, and dispersant, then adding plasticizer and continuing grinding; Step S2: Vacuum treatment and degassing of the slurry by vacuum degassing; Step S3: Casting and molding by casting the high-purity alumina slurry to obtain alumina cast blank sheet; Step S4: Processing the cast blank sheet by drilling holes in the alumina cast blank sheet; Step S5: Lower lamination by hot pressing the hole-processed alumina cast blank sheet; Step S6: Screen printing by screen printing on the hole-processed alumina cast blank sheet; Step S7: Overall hot pressing and lamination by hot pressing the lower hot pressing layer and the screen-printed alumina cast blank sheet; Step S8: Sintering by first removing the binder and then sintering.

The invention discloses a preparation method of micro-particle high-purity ceramic for an electrostatic chuck, and belongs to the technical field of electrostatic chucks. The preparation method comprises the following steps: S1, preparing high-purity aluminum oxide slurry; s2, carrying out defoaming treatment and aging on the slurry; s3, carrying out tape casting, and then drying to obtain an aluminum oxide tape casting blank piece; s4, hole machining; s5, performing lower hot-pressing lamination on the aluminum oxide tape-casting blank sheet subjected to hole processing; s6, carrying out silk-screen printing on the aluminum oxide tape-casting blank sheet; s7, performing integral hot-pressing lamination on the lower hot-pressing lamination and the aluminum oxide tape-casting blank sheet subjected to silk-screen printing to obtain an aluminum oxide blank sheet; and S8, the aluminum oxide blank piece is subjected to glue discharging and sintering, and the high-purity aluminum oxide ceramic piece for the electrostatic chuck is obtained.

The present application relates to the field of ceramics, and particularly to a high-temperature-resistant black colorant suitable for advanced ceramics, a preparation method and applications thereof, wherein the components of the high-temperature-resistant black colorant include, by mass ratio, 15-25% of Co3O4, 8-15% of Cr2O3, 2-5% of MnO2, 3-8% of SiO2, and 40-60% of Al2O3. The present application realizes the thermal expansion coefficient coordination of the colorant and the alumina matrix by introducing a combination of transition metal oxides matching the alumina lattice, thereby inhibiting cracking or peeling caused by interface stress. A composite doping strategy is adopted to make coloring ions (such as Co 2+ , Cr 3+ ) enter the interstitial space of the alumina lattice to form a stable solid solution structure, thereby significantly improving the color stability at high temperatures. Wet ball milling combined with surface modification is used to ensure uniform dispersion of the colorant particles in the alumina slurry and avoid color spot defects caused by agglomeration.

The utility model discloses an aluminum oxide slurry distributing device, which relates to the field of aluminum oxide preparation and comprises a filter frame body, the filter frame body is of a frame body structure with an upper opening and a lower opening, a filter plate is fixed on the inner periphery of the filter frame body in a horizontal unfolding manner, and a distributing and discharging assembly capable of discharging aluminum oxide slurry downwards is arranged above the filter plate. A cloth driving assembly for dispersing cloth above the filter plate in a manner of driving the cloth discharging assembly to transversely move in a reciprocating manner is arranged between the two sides of the filter frame body. The device has the beneficial effects that the distribution driving component and the distribution discharging component are arranged above the filter plate, so that the distribution driving component drives the distribution discharging component to transversely move back and forth, and alumina slurry can be dispersed and discharged on the top surface of the filter plate by the distribution discharging component; the distribution mode of the aluminum oxide slurry is simple and easy to realize, the filter plate is fully utilized, and the labor intensity of workers is reduced.

The invention discloses a preparation method of a superfine aluminum oxide abrasive for sapphire CMP (chemical mechanical polishing). The preparation method comprises the following steps: step 1, putting an aluminum hydroxide precursor into a crucible; 2, putting the crucible into a muffle furnace for calcining; 3, putting the calcined aluminum oxide into a crusher for crushing, taking out the crushed aluminum oxide, mixing the crushed aluminum oxide with water to obtain aluminum oxide slurry, dropwise adding nitric acid to enable the aluminum oxide slurry to be in an acidic environment, and adding zirconium beads into the slurry by using a nylon wet grinding tank for grinding; and 4, adding water and potassium hydroxide into the ground slurry to obtain the polishing solution of the aluminum oxide abrasive. Compared with the prior art, the method has the advantages that when the prepared aluminum oxide abrasive is used for sapphire polishing, the removal rate is high, the polishing service life is long, and the polished surface quality is good.

The invention relates to the technical field of preparation of low-radioactivity aluminum oxide, in particular to a preparation method and application of aluminum oxide powder with low radioactive element content. The alumina powder contains uranium and thorium, and the preparation method comprises the following steps: carrying out slurry mixing and grinding on metallurgical-grade alumina to obtain an alumina slurry raw material with a preset median particle size; the method comprises the following steps: carrying out a neutralization reaction on an alumina slurry raw material by using a mixed gas containing carbon dioxide to obtain a mixed reaction slurry; the pressure of the mixed gas is greater than or equal to 0.5 MPa; carrying out solid-liquid separation on the mixed reaction slurry to obtain a first aluminum oxide solid phase containing uranyl ions and thorium ions; and carrying out solid-phase replacement reaction on the first aluminum oxide by using an extraction solvent containing a silane coupling agent to obtain the low-radioactivity aluminum oxide slurry. According to the preparation method, efficient separation of uranium and thorium ions and an aluminum oxide solid phase is achieved through a neutralization reaction and a replacement reaction, and the content of radioactive elements in a final aluminum oxide powder product is 5 ppb or below.

The invention discloses a high-purity aluminum oxide slurry treatment method and device. The method comprises the following steps: a, conveying high-purity aluminum oxide slurry to screening equipment through a pipeline; b, the screened slurry flows into a material receiving groove; c, the slurry flows into first iron removal equipment from a discharging opening in the lower end of the material receiving groove; d, conveying to filtering equipment through a diaphragm pump; e, enabling the filtered slurry to pass through second iron removal equipment; and f, defoaming the slurry, and conveying the slurry to a storage tank. Efficient screening, impurity removal and filtering of the high-purity aluminum oxide slurry are achieved. According to the technical means, high purity and high insulativity of the slurry in the production process are ensured, meanwhile, the production cost is reduced, the production stability is improved, and therefore high-quality products with competitiveness in the semiconductor material production field are obtained.

The invention discloses aluminum oxide slurry and a preparation method thereof, and a preparation method of aluminum oxide ceramic. The alumina slurry comprises a solvent, a dispersant, an auxiliary dispersant and alumina; the solvent comprises water, and the particle size of alumina is less than or equal to 150nm. Mixing a solvent, a dispersing agent, an auxiliary dispersing agent and aluminum oxide, and carrying out ball milling treatment to obtain aluminum oxide slurry; and carrying out curing treatment and sintering treatment on the aluminum oxide slurry to obtain the aluminum oxide ceramic disclosed by the invention. The preparation process of the alumina slurry and the alumina ceramic is simple, the cost is easy to control, the prepared alumina slurry has low viscosity and good dispersibility, and the alumina ceramic has excellent mechanical properties and thermal conductivity.

The invention belongs to the technical field of powder materials, and particularly relates to rare earth doped alpha-aluminum oxide powder and a preparation method thereof. The preparation method comprises the following steps: mixing aluminum hydroxide, water and rare earth nitrate, and adjusting the pH value of the obtained mixed solution to 10-12 to obtain slurry; and carrying out hydrothermal reaction on the slurry, cleaning the obtained rare earth doped alpha-alumina slurry until the pH value is 7-7.5, and carrying out spray drying to obtain the rare earth doped alpha-alumina powder. According to the invention, aluminum hydroxide is used as a raw material, rare earth nitrate is used as an additive, and the rare earth doped alpha-alumina powder is prepared by a hydrothermal method. In the hydrothermal reaction, the aluminum hydroxide is converted into boehmite, and then is converted into alpha-aluminum oxide; the doping of the rare earth ions promotes the growth of alpha-aluminum oxide crystal grains, so that powder with larger crystals is obtained. The rare earth doped alpha-alumina powder prepared by the invention is single crystal powder, the average particle size of the powder is 40-150 microns, and the sodium content is 0.01-0.02 wt%.

The invention belongs to the technical field of aluminum oxide production, and particularly provides a method for determining an aluminum oxide slurry filtering parameter combination in an aluminum oxide production process, and the method comprises the following steps: determining candidate filtering parameters for filtering aluminum oxide slurry in the aluminum oxide production process according to a single factor control method, the candidate filtering parameters comprise at least one filter cloth aperture, at least one filter cloth material, a slurry temperature interval and a filtering pressure interval; the candidate filtering parameters are combined through an orthogonal method, a plurality of candidate filtering parameter combinations are obtained, and each candidate filtering parameter combination comprises one filter cloth aperture, one filter cloth material, one slurry temperature and one filtering pressure; and determining a target filtering parameter group from the plurality of candidate filtering parameter combinations. According to the technical scheme provided by the invention, the filtering efficiency of the aluminum oxide slurry can be improved on the premise of ensuring the filtering effect of the aluminum oxide slurry.

The application provides a method for 3D printing of a multi-layer heterogeneous ceramic mold shell for titanium alloy casting, which comprises the following steps: dividing a three-dimensional model of the ceramic mold shell into a surface layer, an adjacent surface layer and a back layer, and connecting the surface layer and the back layer through the adjacent surface layer; according to the three-dimensional model, simultaneously extruding and forming the surface layer, the back layer and the adjacent surface layer by using multiple barrels respectively filled with yttrium oxide slurry, aluminum oxide slurry and mixed slurry of yttrium oxide and zirconium oxide, so as to obtain an integrated mold shell; and drying, degreasing, sintering and post-processing the mold shell, so as to obtain a ceramic mold shell for titanium alloy casting. In conclusion, the ceramic mold shell is divided into the surface layer, the adjacent surface layer and the back layer, multiple barrels are used for synchronous cooperation, and multiple modeling materials with different particle sizes are extruded layer by layer to print different areas of the ceramic mold shell, so that an integrated multi-layer composite ceramic mold shell with high surface precision, high surface inertness and high strength is obtained.

Provided is silica-alumina with a high Bronsted acid amount and a manufacturing method for obtaining the silica-alumina. The silica-alumina has a Bronsted acid amount of more than 10 μmol / g and an isoelectric point in the range of 4.5 to 7.0. The method for producing silica-alumina includes an alumina slurry preparation step for preparing an alumina slurry, a silica slurry preparation step for preparing a silica slurry, a silica-alumina slurry preparation step for mixing the alumina slurry and the silica slurry to prepare a silica-alumina slurry, and a reaction step for reacting the silica-alumina slurry with an aluminum compound.