75 results about "Sintering shrinkage" patented technology

The invention discloses an injection molding aluminum alloy feed and a preparation process thereof, the feed is composed of aluminum alloy powder and a compound binder, and the aluminum alloy powder is composed of Si, Fe, Cu, Mn, Mg, Zn, Cr, Ti, Co and Al; according to the technical scheme, aiming at the technical problems that a brittle phase is easy to form due to high magnesium and silicon content of the 6013 aluminum alloy, the interface bonding force is poor, the sintering shrinkage is difficult to control and the like due to a stable surface oxide film, and through collaborative optimization of a formula and a process, the high-magnesium-silicon-content high-magnesium-silicon-content high-brittleness aluminum alloy is obtained; the feeding and finished product performance is obviously improved; and the prepared aluminum alloy part has the advantages of high sintering density, high hardness, high tensile strength, high elongation and the like, and can meet the manufacturing requirements of high-end fields such as aerospace and traffic transportation on complex precision parts.

The invention discloses a low-cost high-polishing titanium alloy plug housing injection molding method, and belongs to the technical field of metal injection molding. The method comprises the following steps: powder preparation, raw material weighing, internal mixing, granulation, injection molding, acid degreasing, thermal degreasing and vacuum sintering, and polishing. Titanium alloy powder used in the method is composite powder formed by adding 0-50 [mu] m non-spherical powder into 0-60 [mu] m spherical powder prepared through a plasma atomization method (PDPA). The cost of the non-spherical titanium powder is far lower than that of spherical titanium powder, and the production cost is relatively reduced by more than 80%; the 0-60 [mu] m spherical powder prepared by the plasma atomization method is high in powder permeability, and sintering densification is facilitated; the sintering shrinkage coefficient of the porous titanium alloy part with the complex shape prepared through vacuum sintering is accurately controlled to be 1.20-1.350, and extra shaping matched equipment is not needed; according to the high-polishing titanium alloy product part manufactured through the method, the density is larger than or equal to 4.45 g / cm < 3 >, the tensile strength is larger than or equal to 950 MPa, the elongation after fracture is larger than or equal to 12%, and the hardness is larger than or equal to 350 (HV).

The invention discloses an LTCC (Low Temperature Co-Fired Ceramic) material with a controllable shrinkage rate and a preparation method thereof. The material comprises microcrystalline glass A and a glass devitrification material B, wherein the glass devitrification material B is obtained by devitrifying microcrystalline glass C according to a specific temperature system. The glass ceramic A and the glass ceramic C have different softening temperatures. And accurately regulating and controlling the crystallization state of the glass crystallization material B by regulating and controlling the crystallization treatment temperature and / or crystallization treatment time of the microcrystalline glass C. The LTCC substrate prepared from the LTCC material can be co-fired with a silver conductor while ensuring sintering compactness and excellent high-frequency performance, and the sintering shrinkage rate is controllable in the range of 14%-18% on the X / Y axis.

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 provides silver powder and a preparation method thereof, and belongs to the technical field of metal powder preparation. According to the method, the silver powder microstructure control agent and the small-particle silver powder oriented growth inducer are used in a combined mode, the pH value, the temperature and the adding mode of the reaction solution are cooperatively controlled, and the large-flake silver powder with the small-particle thick-flake silver powder growing in an oriented arrangement mode is obtained. An oxidizing agent solution and a reducing agent solution are added into a base solution at the same time, sodium citrate in the base solution controls generation of small-particle thick-sheet-shaped silver powder, an alkaline inducer can promote oriented growth of silver powder particles while adjusting the pH of the solution, then target silver powder is prepared, and on the other hand, in an alkaline reaction system, the prepared silver powder is high in sedimentation rate and high in stability. The solid-liquid separation effect is good, and the waste liquid treatment cost is low. Compared with dendritic or traditional single flaky silver powder, the flaky silver powder prepared through the method has the advantages that the sintering shrinkage rate of powder slurry is low, the contact effect between silver powder particles is better, the sintering activity and conductivity are good, and the market application prospect is good.

The invention provides a production size control method for a hard alloy roll collar blank and an intelligent production system, and belongs to the technical field of powder metallurgy. The method aims to solve the problems of low finished product qualification rate and high cost caused by uncontrollable sintering shrinkage of the hard alloy roll collar in the prior art. According to the technical scheme, the method comprises the steps that a set of linear shrinkage coefficients of a hard alloy roll collar pressed blank are designed in advance based on the target finished product size, and the target size of the pressed blank is calculated according to the set of linear shrinkage coefficients and the target finished product size; then, according to the calculated target size, wax-doped powder serving as a raw material is subjected to compression molding, and a compressed blank is obtained; and finally, the pressed blank is transferred into a low-pressure sintering furnace for dewaxing and sintering treatment. According to the method, the quantifiable linear shrinkage coefficient is introduced, empirical estimation is converted into accurate calculation, operation is simplified, the accuracy and consistency of the size of a finished product are remarkably improved, and the rejection rate and the production cost are reduced.

The invention discloses a low-shrinkage lithium silicate heat accumulator and a preparation method thereof, the low-shrinkage lithium silicate heat accumulator comprises the following raw materials by weight: 6-14 parts of lithium carbonate with D50 particle size of 3-10 [mu] m; 50-70 parts of silicon oxide, wherein the D50 particle size is 5-30 [mu] m; 8-25 parts of kaolin and calcined kaolin, wherein the D50 particle size is 2-9 [mu] m; 9-17 parts of aluminum oxide, wherein the D50 particle size is 3-10 [mu] m; 4 to 7 parts of a binder; 0.5 to 2 parts of a surfactant; lithium carbonate, kaolin, calcined kaolin, technological silicon oxide and technological aluminum oxide are adopted, heat preservation is conducted for 3-8 h at the temperature of 1320-1400 DEG C, the lithium-containing silicate heat accumulator with the sintering shrinkage smaller than 2% is obtained, the thermal expansion coefficient of the product at the temperature of 30-1000 DEG C is smaller than 1.3 * 10 <-6 > / DEG C, cracking is avoided after thermal shock at the temperature of 700 DEG C, the heat accumulator has the large specific heat capacity, the specific heat at the temperature of 1000 DEG C is 2.28 J / g / K, and the heat accumulator has the good heat preservation performance. And the heat accumulator can be used for the RTO device with higher requirement on heat performance.

The invention belongs to the technical field of refractory materials, and particularly relates to a composite castable for a cement kiln coal injection duct and a preparation method and application of the composite castable for the cement kiln coal injection duct. 15-20% of silicon carbide particles; 8-12% of dispersed alumina micro powder; 4-6% of calcium aluminate cement; the content of SiO2 in the rare earth modified silica fume is greater than or equal to 94%, and the rare earth modified silica fume is doped with 0.5-1.5 wt% of Y2O3; 3% to 5% of ZrO2-TiO2-Al2O3 precursor powder, 2% to 5% of ZrO2-TiO2-Al2O3 0.1%-0.3% of a water reducing agent; 0.05 to 0.1 percent of a retarder; and the balance of water. According to the castable, ZrO2-TiO2-Al2O3 precursor powder is added, in-situ reaction is carried out at the temperature of 1100-1300 DEG C, micro-expansion and sintering shrinkage are dynamically matched, cracking is avoided, thermal stability is remarkably improved through doping of Zr < 4 + >, and once the ZrO2-TiO2-Al2O3 precursor powder is formed, a Zr-doped aluminum titanate crystal phase cannot be decomposed or reversed in a high-temperature environment in follow-up service, and the structural stability can be kept.

The application relates to a preparation method of a low-density zirconium diboride-silicon carbide foam ceramic material and belongs to the technical field of foam ceramic preparation. The application aims at solving the problems of forming difficulty and sintering shrinkage of the zirconium diboride-silicon carbide foam ceramic. The preparation method is simple. The silicon carbide template prepared by impregnating a ceramic impregnation solution under vacuum conditions is dried and sintered in subsequent steps, and finally, the low-density zirconium diboride-silicon carbide foam ceramic is obtained. The low-density zirconium diboride-silicon carbide foam ceramic material prepared by the application has the characteristics of uniform structure, nanometer-level grains and excellent mechanical properties, and has a good application prospect in the high-temperature heat insulation field.

The invention provides a ceramic pump part and a preparation method thereof. The ceramic pump part is prepared from the following raw materials: silicon carbide particles, carbon black, epoxy resin emulsion, a curing agent, cellulose ether, an inorganic silicon solution and silicon particles. The silicon carbide particles with four-stage particle sizes (500-841 [mu] m, 212-500 [mu] m, 180-250 [mu] m and 109-154 [mu] m) and a specific mass ratio are adopted, so that the solid-phase bulk density is remarkably improved, low-viscosity mold filling is maintained while high solid content is ensured, drying and sintering shrinkage and stress concentration are reduced from the source, and cracking and deformation of large-size or non-uniform-wall-thickness parts are remarkably reduced.

This invention discloses a method for simulating and testing ceramic sintering stress and a method for reducing ceramic sintering stress. The simulation and testing method includes: 1. Measuring the grain size, relative density, and geometric dimensions before and after sintering; 2. Using Abaqus to establish the ceramic geometry and construct a transient heat conduction model; 3. Establishing the viscoelastic constitutive equation for the sintering shrinkage deformation of zirconia ceramics and constructing a sintering shrinkage model; 4. Sequentially coupling the transient heat conduction model and the sintering shrinkage model to perform joint simulation of solid-state sintering, obtaining the simulation results of ceramic sintering stress. The method for reducing ceramic sintering stress includes: 5. Establishing a finite element model of ceramic sintering shrinkage with proportionally distributed grain sizes and calculating the average sintering stress distribution of the grain size proportional distribution model; 6. Comparing the average sintering stress of sintering shrinkage models with different grain size proportions to determine the method for reducing sintering stress. This invention improves ceramic sintering quality and production efficiency.

The present invention discloses a photocurable additive manufacturing aluminum-based ceramic core material with zero sintering shrinkage. Its slurry is composed of a photosensitive resin, a dispersant, and ceramic powder. Among them, the photosensitive resin accounts for 35-45 vol% by volume, the ceramic powder accounts for 55-60 vol% by volume, and the dispersant is added according to 1-5% of the mass of the ceramic powder. Moreover, the photosensitive resin contains 0.4-1% of a photoinitiator. The components of the ceramic powder include alumina, cyanite, and silica. The present invention relates to the technical field of additive manufacturing of ceramic materials. For this photocurable additive manufacturing aluminum-based ceramic core material with zero sintering shrinkage, by adding cyanite to the photocurable ceramic slurry, the expansion generated by the decomposition of cyanite at high temperature compensates for the shrinkage of the ceramic core during the sintering stage. Under the combined action of the decomposition expansion of cyanite and the sintering shrinkage of alumina, zero sintering shrinkage of the ceramic core at a sintering temperature of 1600 degrees is achieved. The present invention can prepare complex ceramic cores with a zero sintering shrinkage rate and excellent comprehensive properties.

The invention relates to the technical field of nano materials, and discloses a nano-silver paste material and a preparation method thereof, and the nano-silver paste material comprises composite silver powder, an organic solvent system and a polyvinylpyrrolidone surface modifier. Wherein the composite silver powder is composed of nano silver wires, polygonal nano silver particles and micron-sized flaky silver powder according to a specific mass ratio, the organic solvent system is a gradient volatile solvent, and the polyvinylpyrrolidone surface modifier forms a thin coating layer. By the adoption of the technical scheme, low sintering shrinkage, high sintering compactness, low void ratio, excellent electric and heat conduction performance and high shear strength can be achieved.

The present invention relates to a method for testing the shrinkage rate of secondary sintering of a ceramic core at high temperature, and belongs to the technical field of shrinkage rate testing. The method for testing the shrinkage rate of secondary sintering of a ceramic core at high temperature comprises the following steps: (1) preparing a standard sample of a core; (2) preparing a wax mold sample; (3) preparing a measuring module; (4) preparing a measuring module; (5) measuring the inner cavity size of a casting; (6) calculating the shrinkage rate A of the secondary sintering of a core at high temperature: bringing the above four length dimensions into the following calculation formula: A=T3 / T2-T4 / T1-C. For each of the multiple wax mold samples in the measuring module, the secondary sintering shrinkage rate A is calculated and the average value is obtained as the secondary sintering shrinkage rate of the core under the corresponding casting conditions. Beneficial effects: The principle is simple, the operation is easy, and it does not rely on professional high-precision measuring equipment. It can effectively convert high-temperature measurement into low-temperature measurement, and solves the problem that the high-temperature secondary sintering shrinkage of the core cannot be accurately reflected by simply relying on the thermal expansion coefficient.

The application discloses a kind of based on numerical simulation's silicon nitride sintering process parameter optimization method, including the following steps: to photo-curing 3D printing silicon nitride ceramic is successively implemented and sintered experiment is debound, micro characterization is carried out to the ceramic after sintering, and second characterization result is obtained;Establish the viscoelastic constitutive equation of silicon nitride ceramic sintering shrinkage deformation, based on the viscoelastic constitutive equation in Abaqus Sintering finite element model is constructed, to obtain the simulation result of transient temperature field and the simulation result of sintering shrinkage deformation;Second characterization result is corrected to finite element model, and verified finite element model is obtained;According to verified finite element model, the original sintering process curve is optimized, and the sintering process curve with the lowest cost and the greatest influence on sintering stress reduction is selected as the optimal sintering process, to realize the optimization of sintering process.The sintering process parameter optimization method not only reduces the cost, but also shortens the experimental period, and the production efficiency is high.

The present invention relates to the field of semiconductor technology. To solve the problems of nano-copper oxidation and sintering shrinkage in the prior art, a composite copper powder, a preparation method thereof, a semiconductor package, and a preparation method thereof are provided. The preparation method of the composite copper powder comprises the following steps: weighing soluble copper salt and a pore-forming agent, dissolving them in a first alkaline solution, and mixing uniformly to obtain a first solution; weighing a reducing agent and a dispersant, dissolving them in a second alkaline solution to obtain a second solution; quickly mixing the first solution and the second solution under stirring and reacting, cooling to room temperature after the reaction ends, performing solid-liquid separation to obtain copper particles; adding the copper particles into a solvent, mixing uniformly, adding a coating agent, and stirring, performing solid-liquid separation and vacuum drying to obtain micron copper; weighing micron copper and nano copper, the mass ratio of micron copper to nano copper being (1 to 81):9, mixing the micron copper and the nano copper, and embedding the nano copper into the concave points of the micron copper to obtain the composite copper powder.

The invention relates to the field of jet bonding forming, and provides high-loading-capacity nickel-based nano ink for jet bonding forming, a preparation method of the high-loading-capacity nickel-based nano ink and part preparation.The preparation method of the ink comprises the steps that a nickel precursor and nickel nano particles are dissolved in a rapid-volatilization solvent, then a dispersing agent is added to regulate and control the rheological property of the ink, and the high-loading-capacity nickel-based nano ink is obtained; finally, uniform and stable ink is formed through stirring and / or ultrasonic treatment. According to the ink, the precursor is added, the stability of the nano particles in a solution is adjusted, the loading capacity of the nano particles of the ink can reach 40-70 wt.%, meanwhile, the formula of the quick-drying solvent and the stable dispersing agent is optimized, and quick curing and stability maintaining after ink jetting are achieved. In the subsequent sintering process, the nickel precursor is heated and self-decomposed into nickel nanoparticles, the nickel nanoparticles are matched with the previously added nickel nanoparticles, so that gradient density distribution is formed between the nanoparticles with different sizes and the base powder to promote sintering, and meanwhile, the nanoparticles with different sizes are filled in gaps of the base powder to improve the sintering performance. And the sintering shrinkage rate is remarkably reduced while material densification is promoted, and finally, high-density and low-shrinkage-rate parts are manufactured.

The application provides silver powder and a preparation method thereof, and belongs to the technical field of metal powder preparation. The application obtains large flaky silver powder by using silver powder micro-morphology control agent and small particle silver powder directional growth inducer in combination, and by synergistically controlling solution pH, temperature and adding mode of the reaction, so that the small particle thick flaky silver powder is directionally arranged and grown. The oxidizing agent and reducing agent solution are simultaneously added into the base solution, the sodium citrate in the base solution controls the generation of the small particle thick flaky silver powder, and the alkaline inducer adjusts the solution pH while promoting the directional growth of the silver powder particles, thereby obtaining the target silver powder. On the other hand, in the alkaline reaction system, the prepared silver powder has a fast settling rate, a good solid-liquid separation effect and a low waste liquid treatment cost. Compared with the dendritic or traditional single flaky silver powder, the flaky silver powder prepared by the application has a low sintering shrinkage rate of the powder slurry, a better contact effect between the silver powder particles, a good sintering activity and conductivity, and a good market application prospect.

The invention provides a diamond grinding tool based on silicon carbide wafer processing and a preparation method and application, the diamond grinding tool comprises a grinding pellet piece and a grinding disc, the grinding pellet piece is provided with Ni powder, a metal binding agent, a ceramic binding agent, a pore forming agent and a wetting agent, diamond abrasive particles and the metal-ceramic binding agent are adopted as raw materials and are mixed with Ni, a certain amount of pore forming agent is added, and the mixture is stirred to be uniform; the preparation method comprises the following steps: sintering for 20 minutes at high temperature and high pressure in a high-temperature mold, removing pressure after sintering, cooling to 810 DEG C, preserving heat for 10 minutes, then cooling to 550 DEG C, and preserving heat for 10 minutes, so that sintering shrinkage can be effectively prevented; compared with a conventional metal-ceramic bond diamond grinding tool, the multi-nickel metal-ceramic bond diamond grinding tool has the advantages that the material removal rate is increased by 18.3%, the overall level of the grinding process and technology can be improved, the quality of a processed product is improved, the preparation period is short, the product cost can be greatly reduced, and the economic benefit is high.

This invention relates to the field of electronic materials technology, specifically disclosing a titanium nitride ceramic electronic paste, its preparation method, and a ceramic electrode. The titanium nitride ceramic electronic paste is prepared from the following components by mass percentage: 50%–80% titanium nitride powder, 10%–50% organic components, 0.5%–5% solid binder phase, and 0–5% additives. This invention uses titanium nitride powder as the functional phase. The physicochemical properties of titanium nitride are similar to those of the ceramic substrate. It is bonded to the ceramic substrate via high-temperature sintering, resulting in sintering shrinkage behavior that is more closely similar to that of the ceramic substrate. This reduces the difficulty of sintering and matching with the ceramic substrate, effectively reducing stress and defects during co-firing, and improving bonding strength and process stability. The paste provided by this invention also has comprehensive advantages such as low cost, excellent dispersibility, good stability, high temperature resistance, and corrosion resistance, and has broad application prospects in the high-end electronics field.

This invention relates to a powder metallurgy forming method for a high-strength guardrail bolt with an anti-loosening structure, comprising: filling a mold with metal-based powder, the mold including a bolt head forming cavity, a lower contact surface forming cavity, a square neck forming cavity, and a screw forming cavity; forming a first annular powder region and a second annular powder region radially within the lower contact surface forming cavity; pressing the metal-based powder to give the first annular powder region a first compaction density and the second annular powder region a lower second compaction density, forming a green blank; pre-sintering and high-temperature sintering the green blank to give the axial sintering shrinkage of the second annular powder region a higher amount than that of the first annular powder region, thereby forming an inclined wedge-shaped anti-loosening surface on the lower contact surface; shaping the sintered blank while retaining the wedge-shaped anti-loosening surface to obtain the guardrail bolt. This invention eliminates the need for external anti-loosening components, improves the anti-slip and anti-vibration loosening capabilities of the connection pair, and balances forming accuracy and large-scale manufacturing requirements.

The application provides a high-thermal-conductivity heating element and a preparation method thereof. The high-thermal-conductivity heating element is prepared from first black silicon carbide powder, second black silicon carbide powder, flaky graphite, polyvinyl alcohol aqueous solution and a small amount of high-thermal-conductivity MgO sintering aid. The particle sizes of the first black silicon carbide powder and the second black silicon carbide powder are different, and the particle size ratio of the first black silicon carbide powder and the second black silicon carbide powder satisfies the Horsfield filling relationship. The application uses two silicon carbide powder raw materials with different particle size distributions, so that the D50 index satisfies the Horsfield filling relationship, the small-particle-size silicon carbide powder can be filled in the gaps formed by the particle accumulation of the large-particle-size silicon carbide powder, the forming density of the pressed silicon carbide heating sheet blank is improved, the requirement for realizing the densification of the heating sheet through the shrinkage of the later high-temperature sintering is reduced, the sintering temperature is reduced, and the loss of the flaky graphite in the sintering process is avoided.

The invention discloses a preparation method, a structure and a test method of a 3-1 type piezoelectric composite material. The preparation method comprises the following steps: cutting a pouring hole in a piezoelectric ceramic wafer; a polymer material is poured into the pouring hole; vacuumizing the polymer material in the pouring hole after the pouring is completed, and removing bubbles in the pouring hole; the piezoelectric composite material relates to the technical field of piezoelectric ceramic preparation, pouring holes are directly cut in a piezoelectric ceramic wafer, the original grain orientation and domain structure of the piezoelectric ceramic wafer can be reserved, the problems of grain random orientation, grain boundary defects or composition segregation caused by powder forming and sintering are solved, and the piezoelectric composite material is obtained. The uniformity of pore size distribution can be ensured, the mechanical strength is improved, and the problem that the uniformity of pore distribution and size is reduced due to pore and density gradient caused by non-uniform filling or sintering shrinkage when the ceramic slurry is poured into a mold to form honeycomb ceramics is avoided.

The invention provides a hollow turbine blade design method. Firstly, a ceramic simulation part is designed based on the size of a mold core of the hollow turbine blade, then the ceramic simulation part is pressed and sintered, the shrinkage rate of the ceramic simulation part during sintering is obtained, and finally a ceramic mold core mold and an appearance mold of the hollow turbine blade are designed based on the shrinkage rate. According to the hollow turbine blade design method disclosed by the invention, the shrinkage rate of the ceramic simulation piece with the similar size during sintering is firstly obtained, and then the ceramic core mold and the appearance mold of the hollow turbine blade are designed according to the shrinkage rate of the ceramic simulation piece during sintering, so that the core sintering shrinkage size of the hollow turbine blade can be effectively controlled; and the size and the flow of the inner cavity of the turbine blade can be ensured, so that the design and the manufacturing of the high-precision hollow turbine blade are realized.

The application discloses a preparation method of spherical nano-barium titanate coated nickel powder and belongs to the technical field of MLCC internal electrode materials. The method comprises the following steps: dispersing nano-nickel powder in water and performing ultrasonic treatment; adding titanium tetrachloride into the water, and then adding a nickel powder dispersion liquid; then adding a barium source, adjusting the pH to alkaline by using lye, stirring and reacting at 60-80 DEG C under normal pressure and in an air atmosphere, and separating and drying to obtain the product. The barium source is barium hydroxide, barium chloride or barium acetate. The application uses cheap titanium tetrachloride as a titanium source to synthesize the barium titanate coated nickel powder with a core-shell structure in an aqueous solution in one step, and the reaction condition is mild, and no organic solvent and inert atmosphere protection are needed, so that the process is simple and the cost is low. The obtained product has a continuous and dense coating layer, the oxidation starting temperature is above 385 DEG C, the volume shrinkage rate at 1200 DEG C is less than or equal to 9.1%, the oxidation resistance and sintering shrinkage matching property of the nickel powder are significantly improved, and the product is suitable for MLCC internal electrode materials.

The invention relates to an ink-jet 3D printing magnesium oxide ceramic powder material and a magnesium oxide ceramic material.The powder material comprises 50-90 parts of dead burned MgO, 10-30 parts of phosphate, 2-7 parts of a precision improving component, 1-10 parts of a sintering aid and 1-10 parts of a sintering shrinkage-reducing flexibilizer. Firstly, an ink-jet 3D printing technology is adopted for preparing a magnesium oxide ceramic green body of a complex structure; and sintering in a high-temperature muffle furnace to obtain the compact high-strength magnesium oxide ceramic. The powder material disclosed by the invention can realize ink-jet 3D printing, has the characteristics of high precision and high degree of freedom, can be used for preparing any ceramic green body in a complex shape, and provides a new way for preparing complex ceramics.

This invention relates to the field of electronic materials technology, specifically disclosing a titanium diboride ceramic electrode slurry, its preparation method, and a ceramic electrode. The titanium diboride ceramic electrode slurry is characterized by being prepared from the following components by mass percentage: 40%–89% titanium diboride powder, 10%–50% organic system, 1%–5% solid binder phase, and 0–5% additives. This invention uses titanium diboride powder as the functional phase. The physicochemical properties of titanium diboride are similar to those of the ceramic substrate. By bonding it to the ceramic substrate through high-temperature sintering, the sintering shrinkage behavior is more compatible, effectively reducing stress and defects during co-firing, and improving bonding strength and process stability.

The invention discloses an AI-based closed-loop glue discharging sintering control system and production equipment, and relates to the technical field of multilayer ceramic capacitor manufacturing processes, the control system comprises an AI decision module, and a data acquisition module, a feature extraction module and an execution mechanism module which are electrically connected with the AI decision module, the control system uses online crystal phase analysis data for sintering control, establishes a process parameter-product performance end-to-end mapping model, realizes automatic monitoring and prediction of the shrinkage rate of the ceramic material by adopting a sintering shrinkage rate compensation model, and automatically adopts a strategy for compensation when the deviation between the real-time shrinkage rate and the predicted shrinkage rate is too large, so that the quality of the product is ensured. The sintering quality can be improved, so that the product quality is improved.

This invention provides a method for preparing gradient HA / ZrO2 bioceramics and the bioceramics themselves, relating to the field of ceramic material preparation technology. The method includes: conducting sintering experiments with different solid contents and different combinations of HA and ZrO2 component ratios to obtain sintering shrinkage data and establishing a sintering shrinkage control model; determining the component ratio of each layer of the ceramic gradient structure according to biomechanical requirements; performing reverse design of the gradient structure based on the component ratio of each layer of the ceramic gradient structure using the sintering shrinkage control model to obtain the required solid content for each layer of the ceramic gradient structure; and preparing HA / ZrO2 composite ceramic slurries with different solid contents according to the required solid content for each layer of the ceramic gradient structure to prepare gradient HA / ZrO2 bioceramics. This invention enables the ZrO2-rich layer and the HA-rich layer to achieve equal shrinkage during co-sintering, fundamentally eliminating interlayer stress and preventing cracking and warping.

The invention discloses a method for reducing anisotropy of a neodymium-iron-boron permanent magnet in the sintering shrinkage process, and belongs to the technical field of rare earth permanent magnet material preparation. The method comprises the following steps: smelting a main phase alloy which hardly contains a rare earth-rich phase; carrying out rapid hardening, hydrogen decrepitation and air jet pulverization to obtain main phase powder with D50 of 3.5-5.0 [mu] m; a rare earth-rich phase thin film layer with the thickness of 100-150 nm is formed on the surface of the powder through magnetron sputtering or steam deposition, and the thin film layer comprises at least one of the R element, Al, Cu, Ga, Zr and Nb; carrying out compression molding under a magnetic field of 1.5-2.0 T; and then carrying out multi-section vacuum sintering and tempering treatment. According to the method, rare earth-rich phases on the surfaces of main phase particles are uniformly distributed, neodymium-rich phase accumulation in the orientation direction is avoided, the shrinkage anisotropy is smaller than or equal to 5%, the yield of the radiation ring is larger than or equal to 96%, and the problem of cracking caused by uneven distribution of the rare earth-rich phases in a traditional process is effectively solved.