202results about How to "High sphericity" patented technology

The invention discloses a carbon-silicon negative electrode material and a preparation method and application thereof, and the preparation method comprises the following steps: S1, carrying out mixed reaction on a lithium source compound, a lanthanum source compound and a titanium source compound to obtain a mixed reactant; mixing the mixed reactant with a carbon source compound, and dispersing and emulsifying to obtain element-doped microspheres; s2, carbonizing the element-doped microspheres in the step S1 to obtain carbides, and activating the carbides to obtain a porous carbon material; and S3, performing silicon deposition on the porous carbon material in the S2 to obtain silicon deposition porous carbon, and performing carbon deposition on the silicon deposition porous carbon to obtain the carbon-silicon negative electrode material. The carbon-silicon negative electrode material disclosed by the invention is high in lithium ion transmission rate, the problem of poor electronic conductivity of silicon is solved, and the electrical property of a battery can be effectively improved.

The invention discloses a silicon-carbon composite material as well as a preparation method and application thereof, and relates to the technical field of battery negative electrode materials. The silicon-carbon composite material comprises active substance particles, and the active substance particles comprise a spherical porous carbon skeleton and nanometer silicon particles. The silicon-carbon composite material disclosed by the invention is high in sphericity degree, the poor pressure resistance caused by more edges and corners in the rolling process is avoided, and the problems that a solid electrolyte interface (SEI) film is continuously generated, the capacity is weakened and the circulation becomes poor due to low strength can be improved.

The invention discloses a preparation method of high-rhenium and low-oxygen spherical tungsten-rhenium alloy powder, which comprises the following steps: proportioning tungsten powder and rhenium powder, adding into a ball mill for ball milling and mixing to obtain uniform composite powder slurry; the composite powder slurry is fed into a spray dryer to be subjected to spray granulation to form sphere-like alloy powder; and the spheroidized powder is subjected to plasma spheroidizing treatment to form the spherical tungsten-rhenium alloy powder. According to the preparation method disclosed by the invention, the tungsten-rhenium suspension slurry with uniformly dispersed components is prepared, and then granulation and spheroidization are carried out, so that the uniform state of the suspension is successfully solidified, oxygen can be reduced, impurities can be removed, and the spherical alloy powder with relatively large granularity and unlimited rhenium adding amount is prepared. The technical route flow is short, the process controllability is high, pilot scale production can be achieved, and the prepared tungsten-rhenium alloy spherical powder is high in density, sphericity degree and uniformity and low in oxygen content.

The invention relates to an additive manufacturing high-temperature-bearing nickel-based superalloy and a preparation method thereof, and relates to the technical field of superalloy materials and additive manufacturing. According to the main technical scheme, the preparation method of the high-temperature-bearing nickel-based superalloy for additive manufacturing comprises the following steps: preparing alloy powder: preparing the alloy powder; wherein the alloy powder comprises the following chemical components in percentage by weight: 17.0 to 21.0 weight percent of Cr, 50 to 55 weight percent of Ni, 5.0 to 5.5 weight percent of Nb, 2.8 to 3.3 weight percent of Mo, 0.75 to 1.15 weight percent of Ti, 0.3 to 0.7 weight percent of Al, 0.2 to 0.5 weight percent of C, 0.1 to 0.3 weight percent of Mn, 0.1 to 0.3 weight percent of Si, less than or equal to 0.015 weight percent of S, less than or equal to 0.02 weight percent of O, 0.01 to 1.0 weight percent of Y and the balance of Fe; and the additive manufacturing step is conducted, specifically, the alloy powder with the set particle size range is screened out from the alloy powder to be subjected to additive manufacturing treatment, and the additive manufacturing high-temperature-bearing nickel-based high-temperature alloy is obtained. The method is mainly used for preparing the in-situ oxide dispersion strengthened additive manufacturing high-temperature-bearing nickel-based high-temperature alloy with excellent high-temperature performance.

The invention belongs to the technical field of additive manufacturing, and relates to a low-density high-entropy alloy high-energy beam additive forming method. The method comprises the following steps: smelting an alloy; alloy crushing; ball-milling the powder; spheroidizing the powder; preparing a sample; heat treatment; and sample structure performance detection. The low-density high-entropy alloy sample prepared through high-temperature vacuum suspension smelting and plasma spheroidizing is high in room-temperature compression strength which exceeds 2300 MPa, the ductility exceeds 20%, the compression strength at the temperature of 1000 DEG C exceeds 780 MPa, meanwhile, the low-density high-entropy alloy powder manufacturing problem is solved, and the low-density high-entropy alloy powder manufacturing method is suitable for industrial production. The method has the advantages of good sphericity, good fluidity, uniform components, no hollow powder or satellite powder, low oxygen content and the like, and provides a powerful basis for promoting the application of high-temperature alloy structure new materials in the aerospace field.

The invention provides a preparation method of a high-rate and high-sphericity lithium iron phosphate positive electrode material, which comprises the following steps: weighing iron phosphate and a lithium source according to a certain proportion, dispersing in pure water, and mixing and sanding to obtain slurry A; under a stirring condition, adding a small amount of fluorine source into the slurry A to obtain lithium fluoride doped slurry B; and under the stirring condition, adding an organic carbon source into the slurry B to prepare an electrostatic spinning solution C, and drying and calcining at high temperature to obtain the high-rate and high-sphericity lithium iron phosphate composite positive electrode material. The preparation method comprises the following steps: synthesizing a lithium fluoride doped stock solution through an in-situ reaction of a fluorine source and a lithium source, and preparing a uniformly doped precursor through electrostatic spinning; the generated lithium fluoride is used as a fluxing agent to promote the formation of high-sphericity lithium iron phosphate in the sintering process; and meanwhile, the doping of fluorine ions weakens the interaction between Li and O, so that the lithium ions can be separated / embedded in a bulk phase during charging and discharging, and the conductive carbon layer is rich in lithium fluoride, so that the migration efficiency of the lithium ions at a positive electrode / electrolyte interface is improved.

The invention relates to the field of metal soft magnetic materials, in particular to a high-frequency high-permeability metal soft magnetic powder core and a preparation method thereof. The preparation method comprises the following steps: S1, screening magnetically soft alloy powder with a preset particle size; s2, preparing passivation powder; s3, preparing granulation powder; s4, a blank is prepared through compression molding; s5, the blank piece is subjected to curing treatment; and S6, the cured part is subjected to high-temperature heat treatment in vacuum, and the high-frequency and high-permeability metal soft magnetic powder core is obtained. The preparation method disclosed by the invention is simple, mild in reaction condition, low in cost and capable of realizing automatic large-scale production. The high-frequency and high-permeability metal soft magnetic powder core prepared by the invention has high frequency, high magnetic induction intensity and high unit power density, particularly, the internal stress of a metal soft magnetic material is released to the greatest extent by adopting high-temperature heat treatment, the coercive force is reduced, the density and the permeability are remarkably improved, and the high-frequency and high-permeability metal soft magnetic powder core is widely applied to DC-DC and power supply circuits with ultrahigh switching frequency and high magnetic conductivity. And a MHz-level power supply circuit.

The invention belongs to the technical field of new energy materials, and discloses a method for preparing special high-purity manganous-manganic oxide for high-end lithium manganate from manganese sulfate, which is characterized in that manganese sulfate is used as a raw material, seed crystals are prepared firstly and then subjected to oxidative synthesis to enable the seed crystals to grow slowly, any additive is not needed, complex procedures such as roasting, crushing and the like are removed, and the method is suitable for industrial production. The manganous-manganic oxide particles with different particle sizes can be prepared, the prepared manganous-manganic oxide product is high in sphericity degree, controllable in particle size distribution, high in tap density and low in specific surface area, and the process has the advantages of being high in automation degree, improving the physical and chemical properties of manganous-manganic oxide, reducing the impurity content in the product and the like.

The invention discloses a ceramic / high-entropy alloy composite particle reinforced aluminum-based composite material and a laser additive manufacturing method thereof. Firstly, ceramic / high-entropy alloy composite powder and aluminum alloy powder are mixed through ball milling to obtain ceramic / high-entropy alloy composite particle reinforced aluminum alloy composite powder, then the composite powder of the three components is laid on a powder bed, laser power, scanning speed, scanning spacing and the like are adjusted, and laser scanning melting solidification is conducted to prepare the ceramic / high-entropy alloy composite particle reinforced aluminum alloy composite powder. And the ceramic / high-entropy alloy composite particle reinforced aluminum-based composite material is formed. The composite material disclosed by the invention is highly compact, so that the ceramic / high-entropy alloy composite particles can effectively improve the mechanical property of the aluminum-based composite material, and can be used for manufacturing high-performance complex parts for aerospace, automobile rail transit and the like.

The invention relates to the technical field of batteries, in particular to a sodion positive electrode precursor material and a preparation method and application thereof. The chemical formula of the sodium ion positive electrode precursor material is Ni F Mn < c > M < d > (O < H >) < 2 > (at) Ni < a-x > F Mn < c > M < d + x > (O < H >) < 2 >, and M is an element doped according to a preset gradient concentration and comprises one of Zn, Cu and Mg; 0.2 < = a < = 0.8, 0lt; b < = 0.5, 0lt; c < = 0.5, 0 < = d < = 0.1, and a + b + c + d = 1, 0lt; x is less than or equal to 0.2, and the morphology is a sphere-like morphology; the invention also provides a preparation method of the sodion positive electrode precursor material, and the prepared sodion positive electrode precursor material has the structural characteristics of uniform phase, high tap density and gradient concentration increase of doped elements from the inner core to the shell, so that the inner core has high specific capacitance, and the shell has high stability; and the preparation process is simple and easy for large-scale production.

The invention discloses a method for preparing titanium-aluminum alloy powder based on a plasma rotating electrode atomization method, and relates to a preparation method of titanium-aluminum alloy powder. The method aims at solving the technical problems that titanium-aluminum alloy powder prepared through an existing method is uneven in particle size, poor in sphericity degree and high in oxygen content, and comprises the steps that firstly, metal raw materials are weighed according to the target titanium-aluminum alloy chemical component proportion, and a uniform cast ingot is obtained through smelting of a vacuum arc smelting furnace; processing the cast ingot into an electrode bar with a smooth surface, mounting the electrode bar on plasma rotating electrode atomization equipment, enabling the electrode bar to rotate at a high speed, melting alloy at the end part of the electrode bar by utilizing a plasma beam generated by a plasma generator, atomizing the alloy into liquid drops under the action of centrifugal force, and cooling and solidifying the liquid drops in a high-purity argon protection atmosphere to form powder; and finally, the powder is collected and screened, finished powder is obtained, the sphericity degree of the powder reaches 95% or above, the oxygen content is lower than 500 ppm, particle size distribution is uniform, and the powder can be used in the fields of aerospace, the automobile industry, energy and the like.

The invention relates to a method for preparing a tungsten-silicon target material based on a plasma rotating electrode atomization method, which comprises the following steps of: (1) carrying out vacuum suspension smelting on a tungsten-silicon raw material to obtain alloy liquid; (2) the alloy liquid obtained in the step (1) is subjected to pouring and ingot pulling in sequence, and a cast ingot is obtained; (3) grinding the cast ingot obtained in the step (2), and granulating by adopting a plasma rotating electrode atomization method to obtain tungsten-silicon alloy powder; and (4) the tungsten-silicon alloy powder obtained in the step (3) is subjected to hot pressed sintering, and the tungsten-silicon target material is obtained. According to the method, the oxygen content of the tungsten-silicon target material can be reduced, introduction of metal and non-metal impurities is avoided, and the compactness of the target material is improved.

The invention discloses a barium titanate coated Ni particle material synthesized under the assistance of a spray drying technology and a method thereof, and belongs to the technical field of metal powder material preparation. The method comprises the following steps: firstly, taking metatitanic acid and barium hydroxide as raw materials, and mixing the metatitanic acid and the barium hydroxide with nano and submicron Ni powder to prepare a mixed solution; secondly, synthesizing a Ni-based composite material intermediate by adopting a spray drying method; and finally, sintering in a tubular furnace to form the barium titanate coated Ni powder. The barium titanate coated Ni inner electrode material is Ni coated BaTiO3 spherical particles with a core-shell structure, the particles are of a core / shell microstructure, a shell layer is a barium titanate coating layer with the thickness of 10-15 nm, and the particle size of the particles is 100-150 nm. According to the method, required equipment can be scaled, components and microstructures are easy to regulate and control, and the method has high sphericity and dispersity, high compactness and good repeatability; the particle size and distribution can be changed by adjusting process parameters; meanwhile, good interface bonding with a ceramic dielectric layer is realized, and the key problems of mismatching of interlayer interface volume shrinkage, easy cracking and the like in the sintering process are relieved.

The invention provides high-sphericity micro-nano silver powder and a preparation method thereof, and belongs to the technical field of metal powder preparation. The preparation method comprises the following steps: preparing a base solution by adopting polyvinylpyrrolidone, silver nitrate, a first reducing agent and a second reducing agent, respectively preparing a silver nitrate solution, a third reducing agent solution and a sodium hydroxide solution, quickly dripping the silver nitrate solution and the third reducing agent solution into the base solution at the same time, and after the reaction is complete, obtaining the silver-silver composite material. And adding a sodium hydroxide solution to adjust the pH value to 6.5-8, fully stirring, standing, separating out settled silver powder, washing, and drying to obtain the high-sphericity micro-nano silver powder. According to the preparation method, the technical scheme is reasonably designed, the characteristics of polyvinylpyrrolidone, sodium borohydride, ascorbic acid and sodium hydroxide are fully utilized, reagents are matched with one another, and preparation and particle size regulation and control of the spherical silver powder are achieved. The adopted raw materials are non-toxic and pollution-free, the technological process is short, the base solution can be used after being prepared, the batch stability is high, and kilogram-level amplified production is achieved.

The present application provides a method for preparing a nano silver powder with high sintering activity, belonging to the technical field of nano silver powder preparation. The method separates the seed crystals from the mother liquor in the crystal nucleus solution, and then stores the seed crystals in a dispersant solution. When preparing the nano silver powder later, the dispersant solution containing the seed crystals is directly poured into a silver nitrate solution, and a reducing agent solution is added dropwise, and the water bath is heated at the same time. After the reaction is complete, a flocculant is added, and the solution is washed. After freeze drying and polishing, a nano silver powder with high sintering activity can be obtained. The present invention stores the seed crystals in a dispersant solution, and the seed crystals can be stored for a long time, and the volume of the seed crystals used in the subsequent reaction to prepare the nano silver powder can be greatly reduced, and the dispersant does not need to be added again when the nano silver powder is prepared later. The present invention prepares silver powder with a particle size between 50-200nm with a simple process, and the silver powder has good dispersibility, good sintering activity, and can be sintered at a low temperature of 180°C, which can be applied to the field of low-temperature sintering nano silver paste.

The invention provides a preparation method of micro low-oxygen spherical TiAl alloy powder, and relates to the technical field of spherical titanium-based alloy powder. The preparation method comprises the steps of raw material selection and treatment of a wire material, preparation of a TiAl composite wire, preparation of a TiAl alloy wire, treatment of the TiAl alloy wire, establishment of a gas system, high-frequency induction preheating, radio frequency plasma smelting and atomization powder preparation which are sequentially carried out. According to the method, through multiple wire twisting, multiple continuous hot drawing, diffusion homogenization annealing, high-frequency induction preheating, radio frequency plasma smelting and atomization powder preparation, the TiAl alloy wire with the evenly-distributed components can be directly prepared at the low temperature, then the TiAl alloy fine powder with the low oxygen content and the evenly-distributed components is prepared, the TiAl alloy fine powder is suitable for additive manufacturing, and the method is suitable for being used for additive manufacturing. The method is high in flexibility, simple to operate, wide in application, low in cost and very suitable for large-scale industrial production.

The invention relates to a preparation method of a modified waste concrete recycled aggregate, which comprises the following steps: crushing waste concrete, screening the crushed waste concrete with a proper particle size to serve as a raw material of the recycled aggregate, washing with a shaking sieve to remove part of edges and corners about to fall off, and carrying out gelation reaction by using modified solutions such as nano silicon dioxide and water-soluble silicate to obtain the modified waste concrete recycled aggregate. According to the invention, fine pores on the surfaces of concrete particles are blocked and repaired, so that the structure is complete and compact, the mechanical strength of the aggregate is enhanced, the porosity and the water absorption rate are reduced, and the water absorption and the mechanical strength are further reduced through phenolic resin coating. The modified waste concrete recycled aggregate is mixed with cement, zeolite powder and the like, the mixture is pressed into a blank, and the artificial stone with excellent mechanical properties and low water absorption is obtained after carbonization curing. The method provided by the invention has good application prospects and environmental protection significance.

The invention provides a negative electrode material and a battery, the negative electrode material comprises secondary particles, the secondary particles comprise primary particles and amorphous carbon connected with the primary particles, and the primary particles comprise graphite; the negative electrode material comprises at least one of an N element and a P element; in the negative electrode material, the corresponding particle sphericity degree is S10 when the cumulative volume distribution percentage reaches 10%, the corresponding particle sphericity degree is S50 when the cumulative volume distribution percentage reaches 50%, the corresponding particle sphericity degree is S90 when the cumulative volume distribution percentage reaches 90%, S10 is larger than or equal to 0.75 and smaller than or equal to 0.85, S50 is larger than or equal to 0.85 and smaller than or equal to 0.9, and S90 is larger than or equal to 0.9 and smaller than or equal to 1.0. The negative electrode material provided by the invention is relatively good in particle sphericity degree, the isotropy of the negative electrode material can be improved, and the specific capacity and the fast charge rate performance of the negative electrode material can be improved.

The invention provides a modified lithium manganese iron phosphate positive electrode material and a preparation method thereof, a positive electrode and a battery, the modified lithium manganese iron phosphate positive electrode material comprises an inner core and a coating layer located on the surface of the inner core, the chemical formula of the inner core comprises LixMnyFe1-yDzP1-zO4 (Ph), D is selected from Se and / or Te, 1 < = x < = 1.05, 0.2 < = y < = 0.8, 0.01 < = z < = 0.055, 1.001 lt; 1-z + h < = 1.055; the preparation method comprises the following steps: mixing a carbon source, a lithium source, an iron source, a manganese source, a D source and a phosphorus source according to a molar ratio of a molecular formula A, grinding and drying to obtain a precursor; performing first sintering on the precursor to obtain a first sample; and mixing and supplementing a phosphorus source, a carbon source and the first sample, and sequentially grinding and secondarily sintering to obtain the modified lithium iron manganese phosphate positive electrode material. According to the invention, the problem of electrochemical performance degradation caused by manganese dissolution is reduced, and the discharge capacity and the cycle stability of the lithium ion battery are improved.

The invention relates to the technical field of electrostatic spraying, and discloses airflow-assisted electrostatic spraying equipment, a preparation method and application, the airflow-assisted electrostatic spraying equipment comprises a material assembly used for conveying a liquid material, a coaxial needle and a triaxial displacement mechanism capable of moving in three axial directions, the material assembly is connected to an outer needle of the coaxial needle, and the airflow-assisted electrostatic spraying equipment further comprises an air source assembly, the gas source assembly is used for conveying pressure-adjustable high-pressure gas to the inner needle of the coaxial needle; a shell of the coaxial needle is connected to an electrostatic generator, and the coaxial needle is fixedly connected with a sliding block of the three-axis displacement mechanism through a needle head fixing support. Compared with electrostatic spraying without airflow assistance, the air source assembly is adopted for conveying high-pressure air, efficient and rapid spraying can be achieved, and the device is suitable for fine spraying of low-viscosity liquid and heterogeneous liquid; compared with static-free mechanical spraying, the sphericity degree of the obtained microspheres is obviously improved, the particle size is smaller and more uniform, and the fog pollution in the spraying process is reduced in a large area.

The invention discloses self-fluxing hard alloy spherical powder and a preparation method thereof, and belongs to the technical field of powder preparation. The preparation method comprises the following steps: mixing and ball-milling a hard phase material, a binding phase material and a fluxing agent material, and then sintering to obtain a self-fluxing hard alloy blank; and then the self-fluxing hard alloy blank is subjected to electric arc micro-explosion, reduction and screening treatment, and the self-fluxing hard alloy spherical powder is obtained. The obtained self-fluxing hard alloy spherical powder is uniform in component, can be designed in a customized mode according to needs, is small in particle size, high in sphericity degree and low in oxygen content, keeps the original performance of the alloy, can be applied to the field of cladding processing, is not prone to material segregation, and can be used for preparing cladding layer products with uniform components.

The invention provides a preparation method of fine low-oxygen spherical Ti-based high-entropy alloy powder, and relates to the technical field of spherical titanium-based alloy powder. The preparation method comprises the steps of raw material selection and treatment of the wire, preparation of the pre-alloyed wire, preparation of the titanium-based high-entropy alloy wire, treatment of the titanium-based high-entropy alloy wire, establishment of a gas system, high-frequency induction preheating, radio frequency plasma smelting and atomization pulverization which are carried out in sequence. Through multiple wire twisting, multiple continuous hot drawing, diffusion homogenization annealing, high-frequency induction preheating, radio frequency plasma smelting and atomization powder preparation, the Ti-based high-entropy alloy wire with uniform component distribution can be directly prepared at a low temperature, then the Ti-based high-entropy alloy fine powder with low oxygen content and uniform component distribution is prepared, and the Ti-based high-entropy alloy fine powder is suitable for additive manufacturing and has good application prospects. The method is high in flexibility, simple to operate, wide in application, low in cost and very suitable for large-scale industrial production.

The invention provides a spherical graphite material and a preparation method and application thereof, and the spherical graphite material meets the following conditions: the r value of the spherical graphite material is gt; 0.7, the sphericity degree of the spherical graphite material is larger than or equal to 0.75, 10 30 nm * 30 nm areas are randomly selected for any cross section of particles of the spherical graphite material, TEM images are obtained respectively, and graphite lattice layer-amorphous carbon layer-graphite lattice layer crystal form change areas exist in the TEM images of not larger than 3 areas. The prepared lithium-ion battery cathode material has the characteristics of high tap density and small orientation, so that the lithium-ion battery cathode material shows excellent processability, and shows the characteristic of low expansion when being applied to the lithium-ion battery cathode material. The graphite material is high in graphitization degree, and shows the characteristics of high capacity and high first efficiency when being applied to a lithium ion battery negative electrode material.

The present invention relates to the technical field of target materials and target material manufacturing, and specifically to a high-conductivity lithium phosphate sputtering target material for solid-state batteries and a preparation method thereof. The high-conductivity lithium phosphate sputtering target material for solid-state batteries of the present invention comprises the following preparation steps: raw material powder mixing, primary ball milling, calcination, secondary ball milling, and hot pressing sintering. The composite powder obtained in the preparation process has excellent sphericity, and the target material finally obtained has high density and low resistivity. When the target material is used as a sputtering target material to prepare a thin film, it can meet the requirements of solid-state batteries for the thin film in terms of conductivity.

The invention relates to a preparation method of TiZrVNbAl alloy powder with high fine powder yield, and belongs to the technical field of alloy powder materials. The diameter of the flow guide pipe in the gas atomization powder preparation process is designed. High-temperature fine fluid is obtained by properly reducing the diameter of the flow guide pipe and increasing the heating power of the bottom of the crucible; meanwhile, the geometrical shape and the position of the nozzle in the gas atomization powder making process are designed, and the annular nozzle is adopted to enhance the coupling effect between the annular nozzle and fluid flowing out of the flow guide pipe. The hole of the annular nozzle is adjusted to be matched with the diameter of the flow guide pipe, the fluid flowing resistance is reduced, and the interaction between the gas and the fluid is further enhanced. And the relative position and angle between the nozzle and the flow guide pipe are adjusted, so that atomized gas can be in better contact with fluid, the fluid can be more effectively atomized by the gas, finer liquid drops are formed, and the fine powder rate is improved.

The invention discloses a high-rate high-nickel cobalt-free positive electrode material and a preparation method and application thereof, the chemical formula of the positive electrode material is LiNi < x > Mn < 1-x-y-z > M < y > N < z > O < 2 >, M is one or more of Al, Zr, Y, W, Nb, Ce, Ti, Mg, Sr, B, P or Si, and N is an MBene material coating layer, 0.5 lt; xlt; 1.0, 0 lt; yt; Yt; 0.1, 0 lt; zlt, zlt; 0.1, 0 lt; x + y + zlt; the preparation method comprises the following steps: 1, selecting a porous precursor, carrying out lithium matching and sintering to obtain a positive electrode material matrix, polishing the positive electrode material matrix, separating out a polishing agent and fine powder generated by polishing, coating an MBene material, and annealing and sintering to obtain the high-nickel cobalt-free positive electrode material with a porous structure inside and a coating layer with stable chemical properties and high conductivity on the surface; when the composite material is used for a lithium ion battery, the pulping viscosity change is small, the rate capability is good, and the cycling stability is remarkably improved.

A method for preparing spherical aluminum hydroxide micropowder includes the following steps: A sodium aluminate solution A is prepared by mixing aluminum hydroxide and sodium hydroxide; after heating, a self-made polyvinylpyrrolidone-g-polysiloxane additive is added, and the mixture is continuously heated and stirred to form solution B; sodium bicarbonate is then added and the reaction is continued with stirring; after the reaction is complete, the mixture is filtered while hot to obtain the filtrate, which is solution C; solution C is heated under stirring conditions, and after the reaction is complete, the temperature is lowered at a certain rate to obtain a mixed product; the mixed product is filtered, washed, and dried to obtain spherical aluminum hydroxide. The spherical aluminum hydroxide prepared by this method has a regular morphology and concentrated particle size distribution, with a D50 of approximately 7-10 micrometers. Compared with irregularly shaped aluminum hydroxide of the same particle size, it has better filling performance, effectively improving the problems of poor dispersibility and high viscosity caused by high filling of aluminum hydroxide in polymer materials, and improving the subsequent processing performance of the material.

The present invention relates to the field of sodium ion batteries, and discloses a positive electrode material precursor, a positive electrode material for a sodium ion battery, a preparation method thereof, and a sodium ion battery. The positive electrode material precursor is spherical and / or quasi-spherical; the sphericity Q of the positive electrode material precursor satisfies: 90%<Q<100%; the D 10 , D 50 and D 90 Satisfy: 0.55<K 90 =(D 90 ‑D 10 ) / D 50 <0.85;wherein, Q=4π×S / (L 2 )×100%, S is the projected area of ​​the precursor secondary particles, and L is the perimeter of the projection of the precursor secondary particles. The positive electrode material precursor has high sphericity and narrow particle size distribution, and in particular, has uniform metal element distribution. When the positive electrode material prepared from the positive electrode material precursor is used in a sodium ion battery, the capacity performance and cycle performance of the sodium ion battery can be significantly improved.

This invention belongs to the field of electronic packaging and soldering materials technology, and relates to a lead-free solder powder for reflow soldering and its preparation method. This lead-free solder powder is based on a Sn-Ag-Cu alloy system, and achieves melt purification, β-Sn grain refinement, and interface IMC stabilization by adding trace amounts of Ce and Ni elements. Its composition, by mass percentage, is: Ag 2.9%–3.1%, Cu 0.45%–0.55%, Ce 0.01%–0.10%, Ni 0.01%–0.05%, with the balance being Sn and impurities. During preparation, a Ce-Ni master alloy is used to introduce microalloying elements, followed by vacuum melting, inert gas atomization, and surface treatment to obtain spherical solder powder. The resulting solder powder has low oxygen content, good wettability, slow interface IMC growth after reflow, high solder joint strength, and excellent thermal cycling reliability, making it suitable for high-reliability electronic packaging applications.

The application belongs to the technical field of polymer materials, and particularly relates to a nylon powder and a preparation method and application thereof. The nylon powder comprises high-viscosity nylon resin, low-viscosity nylon resin and an additive, wherein the relative viscosity of the high-viscosity nylon resin is 1.75-1.85, the relative viscosity of the low-viscosity nylon resin is 1.55-1.65, the mass ratio of the high-viscosity nylon resin to the low-viscosity nylon resin is 10:1-3, and the additive comprises an antioxidant. The high-viscosity nylon resin and the low-viscosity nylon resin with specific viscosities are compounded and used in proportion, the high-viscosity nylon resin serves as a skeleton of a hydrogen storage bottle inner container and provides mechanical property support, and the low-viscosity nylon resin provides fluidity and ensures few defects in bottle forming. The use of the nylon powder of the application improves the mechanical property of the hydrogen storage bottle inner container and the integrity of the inner container structure, and a stable and defect-free type IV nylon hydrogen storage bottle inner container is prepared.