847 results about "Spray Granulation" patented technology

The invention discloses a reaction-sintered silicon carbide setter plate and a preparation method thereof. The reaction-sintered silicon carbide setter plate product is obtained through powder granulation, compaction and reaction sintering. Wherein the silicon carbide powder of the four particle size sections is matched, the particle size sections are uniform, stacking is more reasonable, coarse particles form a frame, fine particles are filled among the coarse particles, the powder structure is compact in property, and the compactness of a green body obtained after blank pressing is guaranteed; and spray granulation is performed after ball milling, so that all the raw materials and auxiliary materials are uniformly mixed. The surface of the green body pressed by a set oil pressure mold is also provided with a concave-convex structure, so that the contact area between the load bearing plate and the bottom of the domestic porcelain is reduced, air circulation between the load bearing plate and the bottom of the domestic porcelain is increased, and adhesion is effectively avoided. The product has the advantages of long service life, high strength and fast heat conduction, solves the problems of low strength, low heat conductivity and short service life of mullite, and also solves the industrial pain point of adhesion of a reaction-sintered silicon carbide setter plate.

The invention belongs to the technical field of ceramics, and discloses a preparation method of fracture-resistant and wear-resistant ceramics. The preparation method comprises the following steps: weighing the raw materials in parts by weight; the preparation method comprises the following steps: mixing 40 parts of potassium feldspar, 10 to 25 parts of albite, 1 to 10 parts of kaolin, 1 to 10 parts of serpentine, 5 to 25 parts of dolomite, 2 to 9 parts of nano zirconium oxide, 0.1 to 1 part of nano cerium oxide, 0.1 to 1 part of nano molybdenum disulfide, 0.1 to 0.8 part of silicon carbide fiber, 0.5 to 2.5 parts of polyethylene glycol, 0.1 to 0.6 part of fullerene trifluoromethyl derivative, 0.1 to 3 parts of sodium dodecyl sulfate, 0.1 to 2 parts of sodium tripolyphosphate and 10 to 60 parts of solvent to obtain slurry; and carrying out spray granulation to obtain a blank, carrying out compression molding to obtain a green body, and sintering to obtain the fracture-resistant and wear-resistant ceramic. The breaking strength of the breaking-resistant and wear-resistant ceramic can exceed 70 MPa, and the length of a grinding pit does not exceed 8.5 mm.

The invention relates to a preparation method of high-strength and high-toughness composite silicon carbide ceramic, which comprises the following steps: mixing 70-82 parts of micron-sized alpha-silicon carbide powder, 5-15 parts of a mixed reinforced phase, 5-10 parts of a sintering aid, 1.9-2.1 parts of a dispersant and 0.9-1.1 parts of a binder to obtain a powder raw material, adding deionized water into the powder raw material, and carrying out ball milling to obtain water-based slurry; carrying out spray granulation on the water-based slurry to prepare spherical granulation powder; and adding the spherical granulation powder into a graphite mold, putting the graphite mold into a hot-pressing sintering furnace, heating to a sintering temperature, and carrying out hot-pressing sintering to obtain the high-strength and high-toughness composite silicon carbide ceramic. By adopting the method disclosed by the invention, the high-performance silicon carbide ceramic material with higher mechanical property and higher toughness can be obtained.

The invention relates to a preparation method of a nickel ion doped modified ferric sodium pyrophosphate positive electrode material, and belongs to the technical field of sodium ion battery positive electrode materials. The nickel ion doped modified ferric sodium pyrophosphate positive electrode material is prepared by adopting an integrated process system of liquid phase uniform mixing, spray granulation and precise segmented calcination. According to the process system, atomic-scale uniform doping of nickel ions and a specific microstructure of a precursor are realized through spray drying, and a plurality of inherent key technical problems of low electronic conductivity, low ion diffusion rate, impurity phase generation and the like of an NFPP material are solved together through a synergistic effect with a subsequent calcining process; furthermore, the discharge capacity of the ferric sodium phosphate pyrophosphate composite material at high rate is improved, so that the battery has relatively high cycling stability.

The invention discloses a preparation method of aluminum nitride by spray granulation, which belongs to the technical field of ceramic preparation. The method comprises: adding aluminum nitride powder and a dispersant into a ball mill for ball milling for 24 to 26 hours, adding an adhesive and a solvent thereto, wherein the adhesive is acrylic resin or PVB, and continuing ball milling for 15 to 18 hours after the adhesive and the solvent are added, the ball milling speed of the ball mill is set to 100 to 200 rpm, the diameter of the ball milling beads is 20 to 50 mm, the number of the ball milling beads is 200 to 300, and aluminum nitride slurry is formed after ball milling; the aluminum nitride slurry is sucked into a granulation tower, and the parameters of the granulation tower are set to: an air inlet temperature of 130 to 140 DEG C, an air outlet temperature of 80 to 90 DEG C, a rotation speed of an atomizing disk of 7000 to 8000 rpm, and a feed pump rotation speed of 50 to 60 rpm; collecting samples at a discharge port of the granulation tower, and then testing the samples and recording the test results.

The invention discloses a nanostructure thermal protection coating resistant to long-time high-temperature oxidation and a preparation method thereof.The nanostructure thermal protection coating takes a ceramic matrix composite material as a matrix, and a bonding layer and a composite component coating are sequentially sprayed to the surface of the matrix. Preparing a nano-structure self-healing additive / Re2Si2O7 spherical powder body; preparing a bonding layer on the surface of the ceramic-based composite material serving as a matrix; and 3, depositing the nano-structure self-healing additive / Re2Si2O7 spherical powder on the surface of the bonding layer to form the composite component coating. According to the preparation method, the self-healing additive / Re2Si2O7 is prepared into the nano-structure spherical powder suitable for thermal spraying for the first time, and a method is provided for implementation of the high-performance material on a thermal spraying nano-structure coating. The prepared coating is stable in phase structure at high temperature, phase change of powder is avoided in the spraying process, and the coating has good thermal expansion coefficient matching performance with a base body.

The invention discloses an energy-saving environment-friendly spray granulation tower for aluminum oxide ceramic material processing, which comprises a bottom plate, a mixing barrel is fixedly mounted at the upper end of the bottom plate, a heating pipe is spirally wound on the outer side of the mixing barrel, a stirring assembly is arranged in an inner cavity of the mixing barrel, a granulation tower box is arranged at the rear end of the mixing barrel, and the granulation tower box is arranged in the inner cavity of the mixing barrel. And the lower end of the granulation tower box is fixedly connected with a collection hopper. According to the energy-saving and environment-friendly spray granulation tower for aluminum oxide ceramic material processing, by starting a driving motor, the output end of the driving motor drives a first stirring shaft to rotate, the first stirring shaft rotates to drive a main cone pulley to rotate, the main cone pulley rotates to drive a transmission cone pulley to rotate, and then through cooperation of a driven cone pulley, the energy-saving and environment-friendly spray granulation tower is driven to rotate. The second stirring shaft can conveniently rotate reversely, so that the materials in the mixing barrel can be fully stirred by a plurality of groups of stirring rods, and the problem that the quality and the size of formed spherical particles do not reach the standard due to the fact that the materials are not uniformly mixed can be avoided.

The invention discloses a preparation method of ultra-fine grain high-entropy carbide-based metal ceramic, which comprises the following steps: step 1, dispersing multi-component carbide powder or micron-sized high-entropy carbide powder in an organic solvent, adding phenolic resin and ceramic grinding balls, and carrying out ball milling; step 2, pre-sintering the dried high-entropy ceramic powder; 3, the obtained high-entropy carbide ceramic powder and metal powder are subjected to conventional ball milling, 1-3 wt% of paraffin or a rubber forming agent is added, a ball milling medium is absolute ethyl alcohol, and then the mixture is subjected to spray granulation; step 4, pressing and forming the granulated powder; and fifthly, the pressed blank is degreased and sintered, and the ultra-fine grain high-entropy carbide-based metal ceramic is obtained. The ultra-fine grain high-entropy carbide-based metal ceramic material with the bending strength superior to 2300 MPa, the fracture toughness superior to 9.5 MPa.m < 0.5 > and the Rockwell hardness superior to 92.0 HRA can be obtained, and the ultra-fine grain high-entropy carbide-based metal ceramic material can be widely applied to the fields of bearing materials, cutting tools, mold materials and the like.

The invention belongs to the technical field of ceramic materials, and discloses a wave-transparent bulletproof ceramic material and a preparation method thereof. The ceramic material comprises the following components in parts by weight: 60-80 parts of alumina micro powder, 20-40 parts of silicon nitride powder, magnesium carbonate powder, lanthanum oxide powder, a polyethylene glycol dispersant, a temporary binder emulsified paraffin and glycerol. The preparation method comprises the following steps: mixing and stirring the raw materials, and fully pulping; grinding and dispersing the slurry through a high-speed grinder; carrying out spray granulation on the slurry by adopting a centrifugal spray granulation tower, and preparing the slurry into composite granulation powder; pressing the granulation powder into a required shape to obtain a green body; and a high-temperature nitrogen gas pressure sintering furnace is adopted for product sintering. The bulletproof ceramic disclosed by the invention has the advantages of low dielectric constant, high toughness and high hardness, and normal communication signal transmission is not influenced while the bulletproof ceramic has excellent protection performance.

The invention relates to the technical field of spray drying equipment, and discloses centrifugal spray drying equipment and a ceramic spray granulation drying method.The centrifugal spray drying equipment comprises a device body, an electric cabinet, an air heater and a spray drying bin, the spray drying bin is installed in the device body, and the electric cabinet and the air heater are fixedly installed at the top of the device body; a heating mechanism and an upwind mechanism are installed in the spray drying bin, and a discharging pipe is fixedly connected to the bottom of the spray drying bin. In the slurry particle heating and drying process, the interior of the spray drying bin can be heated at different temperatures in a sectional mode through the multiple air opening connecting rings, and in the slurry particle descending process, the ascending mechanism can adjust the descending speed and position of slurry particles; by means of sectional type heating, the heating time and heating uniformity of slurry particles are guaranteed, the problem that ceramic particles are broken due to the fact that the heating temperature is too high and heating is not uniform can be effectively solved, and therefore the production quality of the ceramic particles is remarkably improved.

The invention discloses a low-loss manganese-zinc soft magnetic ferrite material suitable for wide frequency and wide temperature and a preparation method thereof, the material comprises the following main components in percentage by mass: 71.25%-71.5% of Fe2O3, 6.0%-7.5% of ZnO and the balance of MnO; the additive is prepared from the following components in percentage by mass: 0.4 percent to 0.5 percent of Co3O4 and 0.07 percent to 0.11 percent of SnO2; the raw materials comprise, by weight, 0.004%-0.008% of SiO2, 0.03%-0.04% of CaCO3 and 0.01%-0.02% of ZrO2; and 0.02% to 0.03% of Nb2O5. According to the present invention, the main component raw materials are subjected to pre-sintering, coarse crushing, sand grinding and fine crushing after the additive is added, spray granulation, and sintering in the nitrogen and oxygen mixed atmosphere, such that the wide frequency, wide temperature and low loss of the manganese zinc ferrite material are achieved, and the application prospect is good when the manganese zinc ferrite material is used for the low-loss electronic transformer.

The invention belongs to the technical field of rare earth thermal spraying, and particularly relates to spherical yttrium oxide powder for thermal spraying and a preparation method of the spherical yttrium oxide powder. The preparation method comprises the following steps: dissolving a yttrium oxide raw material with nitric acid to obtain a yttrium nitrate solution; sequentially carrying out parallel flow reaction, aging, washing and filtering on part of the yttrium nitrate solution and ammonia water to obtain yttrium hydroxide; sequentially carrying out parallel flow reaction, aging, washing and filtering on the residual yttrium nitrate solution and the mixed precipitant to obtain alkaline mixed yttrium; the preparation method comprises the following steps: mixing yttrium hydroxide and alkaline mixed yttrium with water, then adding a dispersing agent and an adhesive step by step, stirring, and carrying out spray granulation to obtain granulated powder; roasting the granulated powder, adding water, carrying out ball milling, then adding the dispersing agent and the adhesive step by step again, and carrying out secondary spray granulation to obtain secondary granulated powder; and sintering the secondary granulation powder at high temperature, and screening. The spherical yttrium oxide powder obtained through the method is high in absolute purity, high in balling rate, good in fluidity, high in apparent density and low in porosity.

A preparation and use method for an Nb5Si3 composite spheroidized powder. The preparation method comprises: A) mixing an Nb powder, an Si powder, PVA and water, and ball milling the resulting mixture to obtain a slurry; and subjecting the slurry to spray granulation and sieving, so as to obtain an Nb5Si3 composite agglomerated powder; and B) subjecting the Nb5Si3 composite agglomerated powder to plasma spheroidization to obtain the product. The use method comprises mixing the Nb5Si3 composite spheroidized powder with NbTiX, wherein X is three or more of Zr, Hf, V, Mo and Ta; Nb and Si in the raw materials are subjected to an in-situ reaction during a laser additive melting process; and in combination with a rapid solidification process, a submicron Nb5Si3 particle-reinforced Nb5Si3 / Nbss dual-phase alloy can be obtained. Compared with a cast alloy having the same components, the Nb5Si3 particle-reinforced phase can be greatly reduced from a size level of dozens of microns to a submicron level, which greatly reduces the brittleness of the particle-reinforced refractory alloy, and significantly improves the strength of the particle-reinforced refractory alloy.

The invention discloses a double-component reinforced 5Y-PSZ dental ceramic material and a preparation method thereof, and relates to the technical field of ceramic material preparation. The method comprises the following steps: mixing ZrCl4 and deionized water, and dropwise adding an ammonia water solution to prepare m-ZrO2 nano ceramic powder; zrOCl2. 8H2O, Y (NO3) 3.6 H2O and deionized water are mixed, the m-ZrO2 nano ceramic powder and polyethylene glycol 2000 are added, and the material is prepared through calcination, spray granulation, hot-pressing presintering and high-temperature sintering. According to the 5Y-PSZ dental ceramic material disclosed by the invention, the nano-scale m-phase ZrO2 is adopted as a reinforcing material and is dispersed and distributed inside the 5Y-PSZ, and through volume expansion generated by t-m phase change of the m-phase ZrO2, the anti-aging performance is guaranteed, and meanwhile, the reinforcement of the 5Y-PSZ dental ceramic material is realized. The invention solves the problem of insufficient strength of the 5Y-PSZ dental ceramic material in the prior art.

The invention relates to the technical field of molten salt, in particular to nitro binary molten salt and a preparation method thereof. The preparation method comprises the following steps: mixing sodium carbonate and a potassium hydroxide solution, and then adding a starch-based grafted crystal inhibitor to inhibit crystallization; adding a nitric acid aqueous solution in two stages, and introducing eutectic seed crystals to guide nucleation at the end of the first stage; crystal distribution is optimized through falling film evaporation and concentration and setting of partial reflux; and after spraying granulation, carrying out short-time melting reforming and controlled cooling in an inert atmosphere. According to the method, the composition uniformity and the structural stability of the molten salt are remarkably improved, so that the product has a melting point close to a theoretical eutectic point, low supercooling degree, high melting latent heat and excellent thermal cycling stability and corrosion resistance, and is suitable for an industrial heat storage system running for a long time.

The invention discloses a silicon-carbon composite material, a preparation method thereof, a pole piece, application and an electrochemical device. The preparation method of the silicon-carbon composite material comprises the following steps: S1, carrying out spray granulation on silicon-carbon precursor slurry to obtain a first precursor; wherein the silicon-carbon precursor slurry is obtained by mixing a silicon source, a carbon source, a pore forming agent and a solvent; s2, carrying out carbonization treatment on the first precursor to obtain a second precursor; and S3, carrying out carbon coating on the second precursor to obtain the silicon-carbon composite material. The battery assembled by the silicon-carbon composite material can effectively inhibit volume expansion of silicon in the silicon-carbon composite material, and the cycle performance of the battery is improved. The preparation method of the silicon-carbon composite material is high in adaptability, lower in production cost, safer and capable of achieving large-scale production.

According to the high-thermal-conductivity flame-retardant copper-clad laminate and the preparation method thereof, the thermal conductivity and the limit oxygen index of a copper-clad plate can be effectively improved, so that the high-thermal-conductivity flame-retardant property of the copper-clad plate is effectively improved; modified aluminum nitride and phosphoric acid modified aluminum nitride powder in the heat-conducting filler can keep good hydrolysis resistance in the ball milling process; polyvinyl butyral and polyethylene glycol are compounded as a binder, so that the modified aluminum nitride has good sphericity and surface smoothness, and the spherical aluminum nitride prepared by water-based spray granulation is suitable for being used as a heat-conducting filler of a thermal interface material; modified silicon dioxide in the heat-conducting filler adopts cerium-doped hollow mesoporous silicon dioxide nanospheres coated with polydopamine, and a corrosion inhibitor MBT (2-mercaptobenzothiazole) is loaded by the cerium-doped hollow mesoporous silicon dioxide nanospheres; controllable release of the corrosion inhibitor MBT and rare earth cerium ions is achieved, the process of corroding the cathode and the anode can be inhibited at the same time, and the corrosion resistance and the corrosion self-repairing performance of the copper-clad plate can be effectively improved.

The invention belongs to the technical field of ceramic material preparation, and particularly relates to a process for preparing a high-compactness silicon carbide ceramic material based on a reaction sintering method, and the process comprises the steps of raw material preparation, material mixing, spray granulation, cold press molding, drying and glue discharging, mold filling, reaction sintering, demolding and grinding. The nano silicon carbide ceramic comprises the following raw materials in parts by weight: 88-92 parts of nano silicon carbide, 8-12 parts of a sintering aid, 2-4 parts of organic polyvinylpyrrolidone, 0.3-0.5 part of polycarboxylic acid and 0.2-0.3 part of a release agent. The sintering aid is a mixture of carbon black and graphite powder in a mass ratio of 3: 2. By optimizing the raw material ratio and the reaction sintering process and organically combining the raw material ratio and the reaction sintering process, the obtained silicon carbide ceramic material is good in compactness, high in toughness and bending resistance and excellent in overall performance, the reaction sintering process is low in energy consumption, the preparation cost is effectively reduced, and remarkable economic benefits and social benefits are achieved.

The invention relates to the technical field of lignite humic acid fertilizer preparation, in particular to a technology and equipment for producing lignite humic acid fertilizer through spraying granulation, the equipment comprises a bottom plate, a temperature rise detection mechanism is arranged above the bottom plate, the temperature rise detection mechanism comprises a cylinder, the cylinder is fixedly installed at the top of the bottom plate, and a temperature rise detection mechanism is arranged above the cylinder. A round rod is rotatably connected to the inner wall of the top of the cylinder, a plurality of stirring blades are rotatably connected to the outer side of the round rod at equal intervals, the section of each stirring blade is a parallelogram, and a plurality of first limiting blocks and second limiting blocks are fixedly connected to the outer side of the round rod at equal intervals; and the outer sides of the first limiting blocks can abut against the outer sides of the corresponding stirring blades. In the heating process, the heating mixing mechanism and the viscosity detection mechanism are integrated together, so that on one hand, the mixing effect is improved, on the other hand, the viscosity of slurry at the temperature can reach a set range after the slurry reaches the set temperature, and the production efficiency and quality are further ensured.

The embodiment of the invention provides a preparation method of a tungsten-copper alloy and the tungsten-copper alloy, and relates to the technical field of alloy preparation.The method comprises the steps that superfine tungsten oxide powder, tungsten salt, copper salt and a polymer additive are added into deionized water to be evenly mixed, and a precursor mixed solution is obtained; carrying out spray granulation on the precursor mixed solution by adopting a spray dryer to obtain spherical tungsten-copper precursor composite powder; roasting the spherical tungsten-copper precursor composite powder to obtain tungsten-copper oxide composite powder, and carrying out segmented reduction on the tungsten-copper oxide composite powder to obtain tungsten-copper composite powder with tungsten grains having a nanocrystalline / ultra-fine grain bimodal distribution characteristic; and the tungsten-copper composite powder is pressed to obtain an alloy blank, the alloy blank is sintered, and the tungsten-copper alloy is prepared. According to the double-peak distribution tungsten-copper composite powder, full densification of the alloy can be promoted through coupling rearrangement of large and small tungsten particles in the sintering process, and the compactness, the heat conductivity and the electric conductivity of the tungsten-copper alloy can be improved.

The invention relates to a thermal / environmental barrier coating and a preparation method thereof. The coating is of a three-layer structure and sequentially comprises a silicon bonding layer, an ytterbium silicate environment barrier layer and a (RE1xRE21-x) 3TaO7 thermal barrier surface layer from inside to outside. The ytterbium silicate environmental barrier layer is formed by mixing Yb2SiO5 and Yb2Si2O7; a (RE1xRE21-x) 3TaO7 thermal barrier surface layer, wherein x is more than or equal to 0.5 and less than 1; in the preparation method, the high-performance thermal / environmental barrier coating is efficiently prepared by adopting the scheme of synthesizing target powder through a solid-phase reaction, preparing a spraying feed through spray granulation and depositing the coating layer by layer through plasma spraying and utilizing the mechanisms of synergistic improvement of functions of the multi-layer coating, doping modification of rare earth elements and the like. The thermal / environmental barrier coating disclosed by the invention has the advantages of excellent CMAS corrosion resistance, good thermal insulation effect and high layer-to-layer thermal matching, and the service life of the SiCf / SiC composite material can be prolonged under the temperature condition of 1500 DEG C by the thermal / environmental barrier coating.

The invention discloses carbon-coated lithium iron manganese phosphate, a preparation method thereof, a positive pole piece containing the carbon-coated lithium iron manganese phosphate, a battery containing the carbon-coated lithium iron manganese phosphate, and an electric device containing the carbon-coated lithium iron manganese phosphate. Lithium iron manganese phosphate slurry with the volume distribution particle size Dv50 of 100-150 nm and lithium iron manganese phosphate slurry with the volume distribution particle size Dv50 of 400-800 nm are mixed, and then spray granulation treatment, sintering treatment and crushing treatment are performed to obtain the carbon-coated lithium iron manganese phosphate. And the carbon-coated lithium manganese iron phosphate is obtained. The carbon-coated lithium manganese iron phosphate prepared by the preparation method provided by the invention can have high gram volume, high powder compaction density, low specific surface area and high cycle stability, and when the carbon-coated lithium manganese iron phosphate is applied to a positive pole piece and a battery, the battery can have high energy density and good cycle performance.

The invention belongs to the field of ceramics, and particularly relates to a high-purity silicon carbide ceramic and a preparation method thereof. Comprising the following steps: adding powder into a ball mill, adding deionized water, stirring, and carrying out ball milling to form water-based slurry; the powder is prepared from micron-scale alpha-silicon carbide powder, nano-scale alpha-silicon carbide powder, polyethylene glycol and polyvinyl alcohol which are different in particle size; carrying out spray granulation on the obtained water-based slurry; and adding the obtained granulated powder into a graphite mold in an oscillating hot-pressing sintering furnace, pre-pressing, heating and boosting to a set sintering temperature and a set sintering pressure, and performing oscillating hot-pressing sintering to obtain the high-purity silicon carbide ceramic. By adopting the method, the mechanical property of the high-purity silicon carbide ceramic can be remarkably improved.

The invention relates to the technical field of thermal protection coatings, and discloses a high-reflection thermal protection coating and a preparation method thereof.LSTN0.125 powder is subjected to spray granulation and then pre-sintered and sieved, and spherical LSTN0.125 ceramic powder is obtained; the alloy substrate is subjected to roughening treatment, and a bonding layer is prepared on the surface of the alloy substrate through the atmosphere plasma spraying technology; the spherical LSTN0.125 ceramic powder obtained in the step S1 is sprayed on the bonding layer through the atmosphere plasma spraying technology, and an LSTN0.125 ceramic layer is obtained; and the LSTN0.125 ceramic layer is subjected to heat treatment, and the LSTN0.125 thermal protection coating is obtained. According to the invention, the LSTN0.125 with high reflectivity is used as a powder raw material of the coating, so that the high reflection performance of the coating in a near-infrared band can be remarkably enhanced, and the effect of isolating high temperature is achieved.

The invention discloses a high-temperature-resistant lightweight aggregate rare earth oxide modified aluminum oxide hollow microsphere as well as a preparation method and application thereof, and belongs to the field of refractory materials. The rare earth oxide modified aluminum oxide hollow microspheres are prepared by adopting a spray granulation method, and aluminum oxide and rare earth oxide mixed powder is subjected to sanding, spray granulation and high-temperature firing to prepare the rare earth oxide modified aluminum oxide hollow microspheres. The rare earth oxide is used as a modifier, and the properties of polarization characteristic, large volume, inhibition of crystal transformation of gamma-phase aluminum oxide at high temperature and the like of the rare earth oxide are utilized, so that the sintering temperature of the aluminum oxide hollow microspheres is reduced, sintering is promoted, crystal boundaries are purified, aluminum oxide crystal grains are refined, and cracks are passivated; the problems that aluminum oxide hollow microspheres are brittle, poor in toughness, high in sintering temperature, prone to damage and the like are solved, and the strength, toughness, hardness, density, wear resistance, corrosion resistance and other performance of the hollow microsphere shell are improved.

The invention relates to the field of battery materials, in particular to a preparation method and application of a high-tap-density spheroidized silicon-carbon negative electrode material. The preparation method of the high-tap-density spheroidized silicon-carbon negative electrode material comprises the following steps: S1, graphite is subjected to shaping treatment; s2, preparing silicon-carbon mixed slurry; s3, carrying out spray granulation on the silicon-carbon mixed slurry; and S4, mixing, coating and carbonizing the silicon-carbon mixed particles and a coating agent. The invention provides the preparation method of the high-tap-density spheroidized silicon-carbon negative electrode material, and the finally prepared silicon-carbon negative electrode material improves the volume expansion of a silicon-based negative electrode and improves the tap density; according to the present invention, the sand milling mixing technology improves the non-uniform mixing of the materials in the precursor slurry of the spray granulation technology, the secondary coating of the particles can be achieved after the carbonization of the binder and the coating agent, and the coated silicon-carbon negative electrode battery has advantages of stable capacity, good cycle performance and wide application potential.

The invention relates to the technical field of nano powder material preparation, in particular to a method for preparing molybdenum powder based on a spray granulation precursor and the molybdenum powder. The method for preparing the molybdenum powder comprises the steps that ammonium molybdate and a pore forming agent are dissolved in ultrapure water at the room temperature, and mixed slurry is obtained; carrying out spray granulation treatment on the mixed slurry to obtain composite powder particles containing the pore-forming agent and ammonium molybdate; the composite powder particles are placed in an oxygen-containing atmosphere to be roasted, and superfine nano molybdenum trioxide is obtained; placing the superfine nano molybdenum trioxide in a hydrogen atmosphere for primary reduction treatment to obtain superfine molybdenum dioxide powder; and the superfine molybdenum dioxide powder is subjected to second-stage reduction treatment, the superfine molybdenum powder is obtained, and the reduction conditions of the first-stage reduction treatment and the second-stage reduction treatment are different. According to the preparation method, the superfine molybdenum powder with good uniformity and dispersity can be prepared.

The invention discloses a preparation method of stable spray granulation silicon nitride slurry and granulation powder, and belongs to the technical field of ceramic materials. According to the invention, absolute ethyl alcohol is adopted as a solvent, so that the problem that silicon nitride slurry is easy to hydrolyze is solved, and the temperature during spray granulation is reduced. On the basis that a dispersing agent is added into slurry, tetramethylammonium hydroxide is added into the slurry, the Zeta potential value of the slurry is increased, the slurry is made to be in an alkaline environment, dissociation of Si-OH groups is promoted, more negative charges are carried on the surface of silicon nitride, meanwhile, zwitterions released by the tetramethylammonium hydroxide form a double-electron layer around silicon nitride particles, and therefore the conductivity of the silicon nitride particles is improved. The dispersity of the particles in the slurry is improved. The silicon nitride powder is more uniformly distributed in a medium such as a binder due to the improvement of the dispersibility, and the silicon nitride slurry with low viscosity, good dispersibility, good stability and good fluidity can be prepared. The slurry can be more symmetrically gathered and formed in the spray granulation process, and the sphericity degree and apparent density of granulation powder are improved.

The utility model relates to the field of organic fertilizer production, in particular to an organic fertilizer spraying granulation device. The existing fertilizer granulation device has the problems that a sieve plate is easy to block and the discharging is not uniform, the granulation effect is influenced, and the granulation efficiency is reduced. The utility model discloses an organic fertilizer spraying granulation device which comprises a bottom frame, a granulation barrel, a breather pipe and the like, the bottom frame is fixedly connected with a granulation barrel, the upper part of the granulation barrel is fixedly connected with a ventilation pipe, the ventilation pipe is communicated with the granulation barrel, the bottom frame is fixedly connected with a motor, and one side, far away from the motor, of the granulation barrel is provided with a discharge port. The pressing rod rotates to drive the two cams to rotate, the cams rotate to intermittently push the push rod to move, the push rod reciprocates to drive the sieve plate to reciprocate, the sieve plate reciprocates to enable falling powder to form a material curtain, and the powder is shaken off into the granulation barrel, so that the uniformity of the powder entering the granulation barrel is improved, and the contact area of the powder and slurry is increased; therefore, the granulation quality is improved.

The invention relates to a lithium manganese iron phosphate composite material, a preparation method and a related device. The preparation method comprises the steps that phosphoric acid, an inorganic manganese source and a reducing agent are added into a solvent, manganese ions in the inorganic manganese source are reduced into divalent manganese ions in the reducing atmosphere, so that the divalent manganese ions and phosphoric acid react to generate a manganese hydrogen phosphate precursor, and the valence state of the manganese ions in the inorganic manganese source is higher than that of the divalent manganese ions; mixing an M source, the manganese hydrogen phosphate precursor and a carbon source, grinding, and performing spray granulation to form a lithium iron manganese phosphate precursor, the M source including an iron source and a lithium source; and calcining the lithium manganese iron phosphate precursor in an inert atmosphere to generate the lithium manganese iron phosphate composite material, the lithium manganese iron phosphate composite material comprises lithium manganese iron phosphate particles and a carbon coating layer, and the carbon coating layer coats at least part of the outer surface of the lithium manganese iron phosphate particles.