230 results about "Grain growth" patented technology

The invention belongs to the technical field of lithium ion battery materials, and discloses a preparation method of a high-first-effect small-particle single-crystal ultrahigh-nickel ternary positive electrode material. The method comprises the following steps: firstly, uniformly mixing an ultrahigh nickel ternary precursor with a lithium source and a tungsten source, performing mechanical densification and pressing to obtain a blocky solid, and then performing four-section program temperature control calcination to obtain a target material. The interface fusion resistance of single crystal growth can be reduced through mechanical densification; a part of the tungsten element forms a Li2WO4 coating layer, and a part of the dopant phase replaces Ni < 2 + >, so that grain growth can be inhibited, a crystal structure can be stabilized, and the first effect is improved; and the microstructure of the material can be accurately regulated and controlled through four-section temperature-controlled calcination. Through a coating-doping-single crystallization synergistic strategy, the electrochemical performance of the material in liquid and sulfide-based all-solid-state batteries is remarkably improved, the process is controllable, and the application prospect is wide.

The invention belongs to the field of hard alloy materials, and provides a modified high-performance non-magnetic hard alloy and a preparation process thereof. The surface of a WC particle is chemically plated with a Ni-P-B-Cr-Cu amorphous shell layer, and a binding phase is converted into Ni3P and Ni3B nanophase through two-stage sintering. The WC alloy comprises the following components in parts by weight: 85-95 parts of WC, 12-25 parts of a binding phase and 0.5-1.4 parts of a grain growth inhibitor, the nanophase accounts for 35-50% of the volume of the binding phase and 35-50% of the total volume of the binding phase, and the grain size is 80-125 nm; the average grain size of WC is 0.6-1.0 [mu] m; and the thickness of an interface P enrichment layer is 8-15 nm (the coverage rate is 85-95%). Through interface engineering and controlled crystallization from amorphous to nanocrystalline, the relative magnetic conductivity is 1.001-1.015, the hardness HRA is 90.5-93.0, the strength TRS is 2.2-3.0 GPa, the toughness KWP is 300-450 N / mm, and the magnetic saturation strength is 0.02-0.15 T. The problem of decoupling of the magnetic property and the mechanical property of a traditional non-magnetic hard alloy is solved, and the non-magnetic hard alloy is suitable for magnetic sensitive environments such as semiconductor equipment, precise measurement, MRI tools and oil service logging.

The invention discloses a pyrochlore structure high-entropy ceramic solidified body material as well as a preparation method and application thereof, and belongs to the technical field of nuclear waste solidification. The preparation method of the high-entropy ceramic solidified body material with the pyrochlore structure comprises the following steps: weighing raw material powder of La2O3, Nd2O3, Sm2O3, Gd2O3, Eu2O3 and ZrO2 according to the proportion in (La0. 2Nd0. 2Sm0. 2Gd0. 2Eu0. 2) 2Zr2O7; the weighed raw material powder is subjected to ball milling treatment, and ball-milled powder is obtained; under the inert gas atmosphere, the ball-milled powder is subjected to heat treatment, and heat-treated powder is obtained; and carrying out spark plasma sintering on the heat treatment powder to obtain the pyrochlore structure high-entropy ceramic solidified body material. The powder is treated by using a heat treatment technology, so that the powder is homogenized, a pyrochlore phase is formed, grain growth is more favorably inhibited, a fine grain structure is obtained, and the irradiation stability and the mechanical property of the pyrochlore material are improved.

The invention discloses a method for improving the thermal stability of a gradient nanocrystalline structure, and belongs to the technical field of metal material processing. According to the method, Mg-RE series alloy is used as a matrix, a matrix alloy ingot is heated for solution treatment, surface strengthening is carried out after water quenching and cooling, a gradient nanocrystalline layer is formed on the surface layer of an alloy sample, finally, the alloy sample is transferred into an aging oven for low-temperature aging, and cooling is carried out, so that the magnesium alloy is obtained. According to the method, the thermal stability of the magnesium alloy gradient nanocrystalline is improved through a synergistic strategy of component design and low-temperature aging, so that the grain growth rate of Mg-RE alloy gradient nanocrystalline structures treated by various different surface strengthening methods in a high-temperature environment can be remarkably reduced; the core bottleneck that a traditional magnesium alloy gradient nanocrystalline material is poor in thermal stability and single in applicable surface treatment method is solved; and the process does not need special equipment, can be seamlessly connected with various existing magnesium alloy surface strengthening production lines, and is low in process cost, simple and convenient to operate and easy to industrially popularize.

The invention belongs to the technical field of refractory materials, and particularly relates to a mullite refractory material with high mechanical property and a preparation method thereof. The mullite refractory material is prepared by taking coal gangue, bauxite and fly ash as raw materials, and the three industrial solid wastes are converted into the refractory material with high additional value, so that the concept of circular economy is met. According to the invention, coal gangue, bauxite and fly ash are used as raw materials, CaF2, V2O5 and lanthanide rare earth oxide are used as sintering aids, the problems of insufficient mechanical properties and overhigh sintering temperature of the mullite refractory material prepared by purely using coal gangue, bauxite and fly ash as raw materials are solved, and the performance of the mullite refractory material can be greatly improved. CaF2 and V2O5 promote substance transport and grain growth, and rare earth oxide inhibits excessive growth of grains. The balance of'promotion 'and'inhibition' is favorable for forming a compact, fine, uniform and interlaced mullite crystal network, and meanwhile, the mullite crystal network has high strength and good toughness.

The invention discloses a high-temperature high-strength zirconium alloy and a manufacturing method thereof and belongs to the field of nuclear engineering materials. The high-temperature and high-strength zirconium alloy comprises the following components in percentage by weight: 1%-10% of Sn, 0.1%-1% of O, 0.01%-3.5% of Al, 0.01%-0.5% of Si and / or 0.01%-0.5% of Ge, and the balance of Zr and inevitable impurities. In the high-temperature and high-strength zirconium alloy, Si and / or Ge can form a precipitated phase which is thermodynamically stable at a high temperature, an alpha-Zr grain boundary is pinned at the high temperature while grain refinement is promoted, solid-state phase change and grain growth in a zirconium alloy matrix at the high temperature are inhibited, and the alloy keeps good mechanical property and structure stability at the high temperature.

The invention discloses a preparation method of a MgO-MgA12O4-ZrO2 nano ceramic eutectic composite material. The preparation method comprises the following steps: S1, preparing powder; s2, flash firing preparation; and S3, high-temperature melting preparation. According to the invention, two technologies of flash sintering and high-temperature melting are combined, the problems of high sintering temperature, easy growth of crystal grains, difficult densification and the like of the traditional eutectic ceramic are solved, and an excellent composite material with a nanoscale eutectic structure is finally obtained; a nanocrystalline blank obtained through flash sintering is crushed and then subjected to high-temperature melting, microdefects and air holes possibly existing in the flash sintering blank are eliminated, the chemical components and the microstructure of a final product are more uniform, and compared with traditional selective laser melting, the method is more convenient and faster to implement and lower in cost.

The invention relates to the technical field of magnesium alloys, in particular to a low-density, high-modulus and ultrahigh-strength magnesium-based composite material and a preparation method thereof.The preparation method comprises the steps that SiC reinforcement particles are pretreated; the raw materials are proportioned according to the mass percent of the components of the magnesium alloy; melting pure magnesium, sequentially adding alloy elements, uniformly stirring, cooling to a semi-solid temperature interval, adding the pretreated SiC reinforcement particles, and casting in a preheating mold to solidify, so as to obtain a magnesium-based composite material cast ingot; the cast ingot is sequentially subjected to solution treatment and extrusion forming; carrying out secondary solution treatment on the magnesium-based composite material bar subjected to extrusion forming; and performing rotary swaging deformation and intermediate annealing treatment on the magnesium-based composite material bar subjected to secondary solution treatment to obtain the ultrahigh-strength magnesium-based composite material. Therefore, the problems that in the prior art, magnesium alloy is insufficient in strength and modulus, a magnesium-based composite material easily generates casting defects and is difficult to deform at room temperature, and the performance of the material is weakened due to grain growth during high-temperature deformation are solved.

The invention relates to the technical field of soft magnetic ferrite materials, in particular to a preparation method of a high-permeability soft magnetic ferrite core material, which comprises the following steps: firstly, preparing FeSiCrBCu soft magnetic alloy powder with uniform components and controllable particle size through a single-roller quenching and hydrogen decrepitation process, and laying a structural foundation for excellent magnetic performance; and then a mechanical stirring-ultrasonic synergistic coating technology is utilized, so that the ferrite precursor uniformly coats the alloy powder, an effective core-shell structure is formed, and solid-phase reaction and crystal grain uniform growth during sintering are promoted. Besides, a multi-task deep learning model (MTL-DL) based on transfer learning is adopted to carry out multi-objective collaborative optimization on the sintering process, accurately match and dynamically adjust key parameters, and accurately regulate and control the material densification process, the grain size and the phase distribution on the microcosmic level, so that the problem that the microstructure and component uniformity are difficult to accurately control in the prior art is solved; therefore, the problems of poor material performance and high power loss are solved.

The invention provides a cold machining manufacturing method of an ultra-fine grain seamless steel pipe. The method comprises the following steps: firstly, selecting a low-alloy structural steel billet with specific components, which comprises C, Si, Mn and microalloy elements of Nb, V and Ti, and heating, perforating and hot-rolling to prepare a pierced billet; and then multi-pass cold deformation treatment is carried out, 5-8 times of cold drawing or cold rolling is carried out on the pierced billet, the deformation of each pass is not lower than 30%, the cold drawing or cold rolling is carried out at the room temperature at the specific speed, and natural cooling is carried out between the passes. Recrystallization annealing is carried out after each pass of cold deformation, heat preservation is carried out for 1-2 hours at the temperature of 650-750 DEG C, and then controlled cooling is carried out. And finally, a finished product is obtained through straightening, head and tail cutting and nondestructive testing. According to the method, through cyclic cooperation of multi-pass cold deformation and recrystallization annealing and the effect of synergistically inhibiting grain growth of microalloy elements, the internal structure of the steel pipe is fully refined and homogenized, and then the comprehensive mechanical properties of the strength and toughness of the finished seamless steel pipe are remarkably improved; and meanwhile, the technological process is stable and controllable, and the product surface quality is excellent.

The invention discloses a processing method for solving grain growth in a solution treatment process of a high-temperature alloy, which comprises the following steps of: 1, obtaining a basic bar by adopting a hot working mode, specifically, carrying out forging cogging on a steel ingot, then carrying out hot working on the steel ingot through a fast forging machine or a rolling mill to obtain the required basic bar, and reserving a certain deformation amount; 2, stress relief annealing is conducted on the basic bar obtained in the step 1, and water cooling is conducted immediately after heat preservation is completed; 3, the bar obtained in the step 2 is subjected to cold drawing; and 4, the finished bar obtained after cold drawing is subjected to solution treatment. According to the method, firstly, residual cold deformation of the bar in the hot working process is eliminated through high-temperature stress relief annealing, then the bar reaches the specified size through cold drawing machining, the cold deformation of the bar is larger than critical deformation, finally, after standard solution treatment, grain structures of all parts of the bar are uniform, and abnormal growth of grains does not exist. The process has the advantages of environmental protection, convenience, flexibility and low cost.

The present application relates to a kind of high-entropy carbonitride ceramics with controllable carbon-nitrogen ratio, high hardness and high elastic modulus and a preparation method thereof, and belongs to the technical field of high-entropy ceramics.To solve the problem that existing preparation methods cannot simultaneously control carbon-nitrogen ratio and mechanical properties of high-entropy carbonitride ceramics, the present application obtains a mixed powder by ball milling and drying Ti powder, ZrH2 powder, Hf powder, Ta powder, Cr powder and carbon black;obtains ceramic powder by heat treatment of the mixed powder in a nitrogen atmosphere;and obtains high-entropy carbonitride ceramics by spark plasma sintering of the ceramic powder.By adjusting the molar ratio of metal powder to carbon black, the present application controls the carbon vacancy concentration of high-entropy system, and then realizes the introduction of nitrogen atoms, which makes it easier to control the carbon-nitrogen ratio of ceramic powder.Spark plasma sintering can effectively avoid grain growth, and obtain dense fine-grained high-entropy carbonitride ceramics in a relatively short time, which is conducive to the improvement of mechanical properties of high-entropy carbonitride ceramics.

The application discloses a preparation method of a high-strength cast magnesium alloy, the alloy containing two non-rare-earth strengthening alloy elements of Sr and Ti, wherein the Ti element is preferentially combined with Al to form AlTi or Al3Ti intermetallic compounds and is gathered along the grain boundary, hindering the growth of alpha-Mg grains, the remaining Al element is combined with Mg to form a beta phase, the grain size is reduced, the morphology of the beta phase is improved, and thus the mechanical properties are improved; the Sr element can strengthen the beta phase on one hand, and can consume the Al element at the solidification front by forming a new Al4Sr phase, so that the volume fraction of the beta phase is reduced; in addition, the Sr element can form an adsorption film of strontium on the grain growth interface as a surface active element, so that the grain growth speed is reduced, the alloy has more time to generate more crystal nuclei when solidifying, and the grains are refined; under the synergistic effect of the two elements, the strength of the magnesium alloy is significantly improved.

The invention discloses a method and device for preparing a mixed crystal structure material through friction stir solid-phase deposition, and belongs to the technical field of heterostructure material preparation. According to the method, firstly, a deposition head is used for carrying out single-layer friction stir solid-phase deposition on a needed material, then a special corrugated roller is used for carrying out cold rolling to enable different positions of the surface of the deposition material to be subjected to different degrees of cold deformation, and therefore uneven high dislocation density is introduced into a deposition layer, and then next-layer friction stir solid-phase deposition is carried out on the surface of the deposition layer. In the friction-stir solid-phase deposition process, static recrystallization and static recovery rapidly occur in a local high-dislocation-density area to maintain fine grains, and grain growth rapidly occurs in a low-dislocation-density area due to heating, so that the whole deposition layer shows the mixed crystal structure characteristic that fine grains and coarse grains coexist; the block mixed crystal structure material can be prepared through stirring friction solid phase deposition and cold rolling circulation.

The application relates to a preparation method of high-intermediate low-loss garnet ferrite with high bismuth substitution, and belongs to the field of microwave ferrite materials. 3+ The application reduces the volatilization of Bi by adding a small amount of H3BO3 and Bi2O3 as additives in the two-milling process, accelerates the growth of the crystal under the driving of the low-melting-point Bi2O3 additive in the sintering process, and accelerates the growth of the crystal under the driving of the low-melting-point Bi2O3 additive in the sintering process. 3+ The volatilization of Bi in the pre-sintering process is reduced by using a lower pre-sintering temperature, the optimal sintering temperature is wider, and the microstructure of the material is effectively improved. 3+ The volatilization of Bi in the sintering process is compensated by using a three-stage progressive holding sintering method in the high-temperature section of the final sintering, the sintering temperature and the holding time are controlled, the crystal grain growth is reduced after the continuous growth of the crystal grain, and the uniformity of the solid-phase reaction is improved.

This application belongs to the field of powder metallurgy technology, specifically a bicrystalline cemented carbide and its preparation method. The preparation method includes the following steps: mixing fine WC powder (2~4μm), Co powder, VC, and Cr3C2, followed by ball milling and spray granulation to obtain fine WC-Co composite powder; mixing coarse WC powder (8~12μm), Co powder, and ultrafine WC powder (0.15~0.25μm), followed by ball milling and spray granulation to obtain coarse WC-Co composite powder; and dry mixing, pressing, and sintering the fine WC-Co composite powder and the coarse WC-Co composite powder to obtain a bicrystalline cemented carbide with a Rockwell hardness of 87~90 HRA and a fracture toughness of 14~17 MPa·m. 1 / 2 The bending strength is 2500~3000MPa. This application prepares coarse and fine WC-Co composite powders separately, so that the inhibitor can effectively suppress the growth of fine WC grains during the sintering stage, while the ultrafine WC can promote the growth of coarse WC grains. This results in the prepared cemented carbide exhibiting a clear dual-scale WC grain distribution, while possessing both high hardness and high toughness. After dry mixing and pressing sintering, the prepared bicrystalline cemented carbide has high density.

The application relates to a preparation method of a high-dielectric high-Curie-temperature garnet ferrite without rare earth, which comprises the following steps: pre-treating raw materials to make the raw materials with different particle sizes basically reach the same particle size state, and then obtaining mixed materials with uniform components through mechanical stirring and one-time granulation, so that ideal pre-sintering effect can be realized. Meanwhile, three kinds of second grinding materials with different pre-sintering temperatures and particle sizes are uniformly mixed to control the sintering activity of the powder, and the sintering process is matched, so that the microstructure of the sintered body can be finally improved, the porosity of the ferrite material is reduced, and the ferromagnetic resonance line width is reduced. Through the combined substitution of bismuth, zirconium and calcium elements and the adjustment of the preparation process, the particle size of the powder is adjusted, the sintering stage is controlled to the end of continuous grain growth, the microstructure of the garnet ferrite material is improved, and finally the ferrite material with high dielectric constant, high saturation magnetization, low ferromagnetic resonance line width and high Curie temperature is prepared.

The invention belongs to the technical field of microstructure simulation in the solidification process, and particularly relates to a nickel-based superalloy laser welding solidification structure evolution law prediction method and system.The method comprises the steps that simulation parameters are determined, a macroscopic temperature field is simulated to obtain molten pool temperature field data, a cellular automaton model is constructed, and grids are divided; initializing state variables such as component concentration and solid-phase fraction; coupling temperature field data, solving an optimized solute diffusion and redistribution equation to obtain a concentration field, updating a solid phase fraction according to local supercooling drive, and marking grain growth; counting a solid-phase fraction, and updating a solid-phase position; and judging whether the temperature of the cladding layer is lower than the solidus temperature and the solid fraction reaches a complete solidification threshold value or not, and if yes, outputting weld microstructure and target element concentration data. According to the method, the evolution law of the welding macroscopic temperature field and the structure and solute concentration field can be effectively predicted, experiments are replaced with numerical simulation, the cost is reduced, the technical blank is filled up, and reliable support is provided for precise regulation and control of the nickel-based high-temperature alloy laser welding process.

Broadband high T c High-conductivity manganese-zinc ferrite and preparation method, belong to ferrite material preparation technical field. High specific surface area raw material is adopted, contact area of powder in ball milling process is increased, reaction activity is improved, and sintering temperature is reduced; MnZn ferrite main formula adopts iron-rich zinc-deficient system, superexchange interaction is enhanced, and material Curie temperature is realized; secondary ball milling introduces combined additives, sintering process grain growth mechanism is regulated by means of fluxing and crystal resistance dual effects, Co2O3 is used to compensate MnZn ferrite magnetic crystal anisotropy constant, and initial magnetic permeability is improved; CaSiO3 is introduced, and is enriched in grain boundary in the sintering process, grain boundary resistivity is improved, and magnetic permeability frequency characteristic is improved; in the sintering process, oxygen partial pressure is accurately controlled in the holding and cooling stages, Fe 2+ Ion generation amount is influenced, sample resistivity is improved, and suitable sintering temperature and holding time are beneficial to grain growth and material densification.

The application relates to a dual-phase high-entropy ceramic material for high-temperature thermal barrier coatings and a preparation method thereof, in particular to a dual-phase high-entropy ceramic (La 0.2 Nd 0.2 Gd 0.2 Y 0.2 Ho 0.2 )2Zr2O7 with low thermal conductivity and high thermal expansion coefficient, which is mainly used for thermal isolation, thermal barrier coatings and other applications in high-temperature environments. The application is prepared by adopting a solid-phase reaction sintering process through accurate design of the combination of rare earth elements, forms a stable dual-phase structure, effectively inhibits grain growth through grain boundary pinning, and thus maintains a nanoscale grain structure. Meanwhile, the material can efficiently block heat transfer at high temperatures through optimization of phase proportion, and the thermal expansion characteristics are matched with a metal base layer, effectively avoiding the falling risk caused by the difference in thermal expansion of the two, and thus greatly improving the service life and reliability of the material in a high-temperature environment. The high-entropy ceramic material of the application can be widely applied to fields with high demand for high-temperature thermal isolation in aerospace, aviation, automobile industry and the like, is especially suitable for thermal barrier coatings, high-temperature thermal insulation materials and other high-temperature thermal insulation applications, and has important engineering application value.

The present application relates to a kind of preparation of complete mosaic-like barium strontium titanate solid solution ceramic sheet, which comprises the following steps: (1) two initial powders are mixed uniformly. After the stoichiometric ratio of nano barium titanate powder and nano strontium titanate powder is mechanically mixed by planetary ball mill for 24h, it is dried and ground to obtain the powder to be sintered;(2) the powder to be sintered is placed in graphite mold twice, the two powders are separated by two carbon paper, and pre-pressed in hand rotating tablet press and discharge plasma sintering furnace;(3) discharge plasma sintering is carried out, and appropriate sintering parameters are set, and sintering program is started, and after sintering, it is first rapidly cooled to a safe temperature 900 DEG C where grain growth is not easy, and then slowly cooled to 600 DEG C at 5 DEG C / min;(4) the sintered sample is placed in muffle furnace, and annealed at 800 DEG C for 10h, to obtain two relatively complete mosaic-like barium strontium titanate solid solution sheets.

Disclosed is an element including a conductive feature at a contact surface of the element and a nonconductive region at the contact surface in which the conductive feature is at least partially embedded. The contact feature includes a conductive material and an amount of impurities at a grain boundary of the conductive material. The impurities have a non-alloying material that does not form an alloy with the conductive material at a bonding temperature.

The application discloses a lead-free heavy-load copper-tin-silicon sliding bearing material and a preparation method thereof, and belongs to the technical field of bearing alloy materials. The lead-free heavy-load copper-tin-silicon sliding bearing material comprises tin 10 wt.%, silicon 2 wt.%-6 wt.% and the balance of copper in terms of mass percentage. The sliding bearing material only contains three elements of copper, tin and silicon, has simple composition and does not contain lead element, and the obtained bearing material is non-toxic and friendly to the environment. The material is prepared by adopting a spark plasma sintering process, powder particles are directly heated by pulse current, the surface of the particles is activated by a spark plasma, rapid densification sintering can be realized at a lower temperature, grain growth, Sn element segregation and Si phase coarsening are effectively inhibited, and the density, mechanical properties and wear resistance of the bearing are significantly improved, and the process has the advantages of energy saving and high efficiency.

The application discloses an in-situ self-generating ceramic particle reinforced low-tungsten-content composite material, and a preparation method of the in-situ self-generating ceramic particle reinforced low-tungsten-content composite material.The low-tungsten-content composite material is composed of the following components in percentage by mass: W 59% to 69%, Ni 21% to 28%, Fe 9% to 12%, and ceramic reinforcing phase 1%.The tungsten content in the material system is greatly reduced, the toughness of the bonding phase is significantly increased, the plasticity and processing performance are improved, the W atoms in the bonding phase are difficult to diffuse to the surface of other W grains during the sintering process, the long-range migration is blocked, the W grain growth is effectively inhibited, the size of the in-situ generated ceramic particles is small, the distribution is uniform, the interface between the metal matrix and the ceramic particles is pure and firm, the strong dispersion strengthening and fine-grain strengthening effects can be produced, and the application of the low-tungsten-content composite material is suitable for the fields of aerospace, radiation shielding and precision instruments.

The application discloses a high-strength ceramic metallization method, and innovatively obtains a ceramic grain growth agent, which comprises 75wt%-85wt% metal oxide powder A, 5wt%-10wt% binder A and 5wt%-20wt% solvent A. The ceramic grain growth agent is coated on the position of an alumina ceramic substrate which needs to be metallized, and after sintering, a fine grain and coarse grain double-layer structure is formed on the ceramic substrate. The fine grains in the inner layer can improve the strength of the ceramic substrate, and the coarse grains in the surface layer can improve the penetration pressure of the glass phase in the ceramic substrate during subsequent metallization sintering, promote the penetration of the glass phase in the ceramic substrate into the metallization ink layer, improve the bonding strength of the metallization ink layer and the ceramic substrate, and thus ensure the sealing strength of the ceramic substrate and the metal piece.

This invention provides a method for producing 270MPa grade hot-dip galvanized deep-drawing steel strip. The method controls the chemical composition, the hot rolling process (including soaking temperature, final rolling temperature, and coiling temperature), and the hot-dip galvanizing process (including annealing temperature, galvanizing temperature, finishing, and tension leveling). This results in hot-dip galvanized steel strip with excellent mechanical properties (Rp0.2 = 185–255 MPa, Rm ≥ 270 MPa, A50mm ≥ 42%, n90 ≥ 0.17). It effectively overcomes the problems of mixed crystals and performance deterioration in the pickling-hot-dip galvanizing technology during annealing due to lack of deformation recovery, recrystallization, and grain growth. The product's microstructure is 100% ferrite with a ferrite grain size of 8.0–10.5. Furthermore, the pickling-direct hot-dip galvanizing process used in this invention omits the conventional cold rolling step, reducing process costs.

This application discloses a perovskite-structured high-entropy ceramic material with excellent dielectric temperature stability. The chemical formula of the high-entropy ceramic material is (Ca... 0.2 Sr 0.2 Ba 0.2 Mg 0.2 Bi 0.1 Na 0.1 (Ti1) x Zr x O3, x=0.05~0.2. This application employs an A-site high-entropy material composition design that enables elements to break through the solid solution limit, achieving greater solid solubility in the material system. By using Zr 2+ Ti at the B site in ion-substituted ceramics 2+ The composition design approach successfully achieved B-site ion doping, resulting in well-grown, dense grains within the ceramic. The sample microstructure exhibited few pores, with elements uniformly distributed throughout the ceramic without agglomeration. By optimizing and controlling the ceramic's microstructure, the dielectric ceramic obtained in this application possesses a high dielectric constant and excellent temperature stability, with capacitance-temperature variations meeting both X7R and X6R capacitor standards.

The invention relates to the technical field of non-oriented silicon steel, in particular to low-cost high-performance non-oriented silicon steel and a preparation method. The steel comprises the following chemical components in percentage by weight: less than or equal to 0.0027% of C, less than or equal to 1.3% of Si, less than or equal to 1.4% of Als, less than or equal to 0.5% of Mn, 0.05%-0.30% of P, 0.003%-0.0045% of S, less than or equal to 0.002% of N, 0.0004%-0.0025% of B, less than or equal to 0.0040% of Nb + V + Ti and the balance of Fe and inevitable impurities. The heating and tapping temperature is controlled to be 1000-1150 DEG C, hot rolling is conducted, the finish rolling temperature is controlled to be 850-1000 DEG C, the coiling temperature is controlled to be 700-800 DEG C, and improvement of the structure of a hot-rolled plate is promoted; cold rolling is carried out to control the specification of a corresponding finished product, and crystallization and grain growth are completed at the temperature of 780-950 DEG C in a soaking section of a continuous annealing unit. And compared with the main body alloy element silicon, the electromagnetic performance of the product is greatly improved under the same-grade original process condition.

The application provides a kind of grain texture synergic control's ceramic copper-clad plate oxygen-free copper strip, by mass percentage, chemical composition is: Cu is greater than or equal to 99.97%, O is less than or equal to 0.0005%, P: 0.0015%~0.0025%, Mg: 0.005%~0.01%, Sn: 0.005%~0.01%, the remainder is inevitable impurity.The application also provides the preparation method of the above copper strip, based on multiple rolling+intermediate annealing composite process.The application has the advantages that: through the microalloying treatment of oxygen-free copper, simultaneously using multiple rolling+intermediate annealing composite process, by adjusting the reduction distribution, the ratio of deformation texture and recrystallization texture is optimized, effectively inhibits high temperature grain growth;The prepared copper strip has high conductivity, high thermal conductivity, excellent surface quality, low plane anisotropy, and the grain is small and uniform after high temperature annealing, which significantly improves the high temperature resistance.

The invention relates to the technical field of hard alloy for synthesis of superhard materials, and particularly discloses a hard alloy holding-up hammer for synthesis of high-purity large single crystal diamond and a preparation method of the hard alloy holding-up hammer. The holding-up hammer material is composed of the following components in percentage by weight: 80%-88% of WC, 4%-8% of Co, 2%-5% of TaC, 3%-7% of TiC and 0.5%-2% of Cr3C. Wherein WC serves as a hard phase, Co serves as a binding phase, TaC inhibits grain growth, TiC nanoparticles are dispersed and distributed to form a pinning effect, and Cr3C2 improves the wettability of the binding phase and improves the oxidation resistance. The preparation method comprises the steps of raw material selection and ball-milling mixing, vacuum drying and sieving, cold pressing and cold isostatic pressing forming, gradient sintering and grinding and subzero treatment.