39results about How to "Small grain" patented technology

The invention relates to the technical field of circuit board manufacturing, and provides a circuit board manufacturing method and a circuit board, and the method comprises the steps: electroplating a golden finger on a production board through an electroplating lead; covering selective printing ink on the part of the electroplated lead and the golden finger; forming at least one finished board on the production board along the routing forming line; carrying out bevel edge processing on the finished board; covering an OSP film on the finished board; and removing the selective ink. According to the circuit board manufacturing method, after the golden finger is electroplated, the part of the electroplated lead and the golden finger are covered with the selective ink, and the selective ink is removed after the OSP process, so that the ratio of the area of the exposed gold layer to the area of the nickel layer and the copper layer at the bevel edge in the OSP process is small, that is, the galvanic effect is not obvious, and the nickel layer and the copper layer are slightly corroded; and the risk that the nickel-gold layer tilts and falls off is reduced, so that the risk of short circuit is reduced.

The invention discloses a low-frequency and differential-phase pulse combined electromagnetic continuous casting method, which belongs to the field of metal material preparation and processing, in the processes of semi-continuous casting, horizontal continuous casting and vertical continuous casting, A + 2B excitation coils are placed in a crystallizer jacket in the direction parallel to the central axis of a cast ingot, and A and B are integers greater than or equal to 1; the 2B excitation coils are divided into a group B1 and a group B2; a coils form a group; a power supply control system with a plurality of sets of built-in control circuits is utilized to respectively output two different currents and voltages which are applied to three groups of magnet exciting coils; one set of circuit system outputs low-frequency alternating-current voltage and sinusoidal current and generates a low-frequency alternating-current electromagnetic signal; the other set of circuit system outputs two groups of square-wave pulse voltage and zigzag pulse current; and a low-frequency electromagnetic field and a differential-phase pulsed magnetic field are applied to melt combinations with different heights in the crystallization sleeve, so that the electromagnetic utilization rate is increased, grains are refined, and the ingot casting quality is improved.

The invention provides a black aluminum oxide ceramic material as well as a preparation method and application thereof. The preparation method comprises the following steps: (1) mixing aluminum oxide, magnesium oxide, silicon dioxide, iron oxide, manganese oxide, chromium oxide and a solvent to obtain an aluminum oxide ceramic mixed solution; (2) mixing the alumina ceramic mixed solution with a binder, and grinding to obtain alumina ceramic powder; and (3) carrying out cold pressing treatment on the aluminum oxide ceramic powder, and carrying out vacuum pressureless sintering treatment to obtain the black aluminum oxide ceramic material. The black aluminum oxide ceramic material prepared by the method disclosed by the invention is relatively small in crystal grain, relatively small in pore and relatively high in density, and has relatively high compactness and thermal conductivity.

The invention provides a magnesium alloy electric arc additive component and a manufacturing method and application thereof, and belongs to the technical field of electric arc additive manufacturing. The manufacturing method of the magnesium alloy electric arc additive component comprises the following steps that a magnesium alloy base plate is fixed to a printing table, a magnesium alloy wire is conveyed to the position below a welding gun, single-channel layer-by-layer reciprocating welding is carried out, after welding of each layer is completed, an oxidation film on the surface of a printed piece is cleaned, and after the interlayer temperature reaches 80-100 DEG C, welding of the next layer is carried out; and the steps are repeated to the target height, and the magnesium alloy electric arc additive component is obtained. According to the manufacturing method of the magnesium alloy electric arc additive component, control over internal defects of the magnesium alloy and good interlayer combination can be achieved, the obtained magnesium alloy electric arc additive component is small in mechanical property anisotropy, and the strength and plasticity are remarkably improved.

The invention discloses a method for manufacturing nickel-based superalloy by regulating and controlling laser additive materials through portable ultrasonic impact equipment, a nickel-based superalloy structure is obtained on a substrate according to the following steps on the substrate for at least one time, and the step comprises the steps that nickel-based superalloy powder is subjected to N times of laser melting deposition on the substrate to form N deposition layers, wherein N is equal to 1-10; and performing primary ultrasonic peening on the deposition layer on the substrate. The microhardness of the nickel-based superalloy prepared through the method is remarkably improved, the improvement rate ranges from 15% to 40%, and the method has the advantages of being convenient to use, low in cost, rapid in forming, easy to operate, capable of conducting machining treatment according to requirements, wide in application range and the like.

The invention discloses a high-density perovskite thin film, a preparation method and application of the high-density perovskite thin film in X-ray detection. The preparation method of the high-density perovskite thin film comprises the following steps: coating an electron transport layer with a precursor stock solution containing a perovskite material and an auxiliary crystallization additive, and then drying. The perovskite material is selected from one or more of FACs2AgBiBr6, FAMACsPbBr3, CsPbBr3, MAPbBr3, Cs2AgBiBr6 and MAPbI3, and the perovskite material is selected from one or more of FACs2AgBiBr6, FAMACsPbBr3, CsPbBr3 and MAPbI3; the auxiliary crystallization additive is selected from thiourea, biuret, ammonium chloride and the like; the precursor solvent is selected from dimethyl sulfoxide, dimethyl formamide and the like. By adding the auxiliary crystallization additive, homogeneous crystallization of perovskite is promoted, and the prepared film has high compactness, low defect rate, flat surface and controllable thickness, and is suitable for large-area devices.

The invention discloses a high-work-function metal oxide target material and a preparation method thereof. The preparation method comprises the following steps: mixing high-work-function metal oxide powder, indium oxide powder and zinc oxide powder into mixed powder according to a set mass ratio; putting the mixed powder into deionized water, adding a dispersing agent, and blending to obtain slurry; the slurry is subjected to high-energy sanding, and a binder is added before sanding is finished; performing spray granulation on the slurry to obtain spherical granulation powder; carrying out compression molding on the spherical granulation powder, and carrying out cold isostatic pressing to obtain a target material biscuit; and the target biscuit is subjected to degreasing and sintering integrated treatment, and the high-work-function metal oxide target is obtained. The high-work-function metal oxide target material disclosed by the embodiment of the invention is small in grain size, uniform in distribution, high in target material density and excellent in electrical property, and can be used for preparing a flexible OLED anode layer thin film material, the device structure is simplified, and the cost is reduced and the efficiency is improved.

The invention discloses a sintering method for effectively reducing the ferromagnetic resonance line width of Bi-substituted garnet ferrite with a high dielectric constant, and belongs to the technical field of ferrite materials, the sintering method is a sintering route of heating-multi-stage high and low temperature alternation-cooling. According to the preparation method, the ferromagnetic resonance line width delta H of the garnet type high-dielectric-constant ferrite is improved, the grain size is increased, abnormal growth of grains after long-time sintering is avoided, the sintering difficulty of the Bi-substituted high-dielectric-constant microwave ferrite is reduced, the sintering quality of the ferrite is improved, and the sintering cost is reduced. The improvement of the batch production reliability and stability of the garnet high-dielectric-constant ferrite is facilitated, the development of a batch production process of high-dielectric-constant products is promoted, and the miniaturization development of microwave ferrite devices in China is assisted.

The invention discloses barium titanate-based high-entropy dielectric ceramic as well as a preparation method and application thereof, and belongs to the technical field of dielectric energy storage ceramic materials. According to the barium titanate-based high-entropy dielectric ceramic disclosed by the invention, element volatilization in the sintering process is compensated by optimizing the numerical value of x, and meanwhile, the doping content of the elements is regulated and controlled, so that the barium titanate-based high-entropy dielectric ceramic is favorable for simultaneously obtaining excellent energy storage performance and dielectric property, and has excellent dielectric property; the barium titanate-based high-entropy dielectric ceramic is favorable for obtaining ceramics with lower loss and smaller dielectric fluctuation, has good temperature stability, low remanent polarization, large effective energy storage density and excellent dielectric properties, and solves the technical problem of large dielectric loss of the existing material.

The invention provides a needle-like aggregate ZSM-5 molecular sieve as well as a preparation method and application thereof. According to the preparation method, metakaolin is used as an aluminum source and is mixed and melted with an alkaline substance, so that metakaolin is softened, and subsequent mixing with substances such as a silicon source is facilitated. According to the preparation method, metakaolin is taken as an aluminum source, an obtained molten product is mixed with a silicon source, a template agent and a solvent, and then hydrothermal crystallization treatment is carried out, so that the molecular sieve grows into a special morphology of needle-like aggregates, single crystal grains of the needle-like aggregates are small, intergranular mesopores exist among the aggregates, and the molecular sieve has a high molecular weight. The total specific surface area, the micropore specific surface area, the mesopore specific surface area, the mesopore volume and the micropore volume of the synthesized ZSM-5 molecular sieve are favorably improved. The needle-like aggregate ZSM-5 molecular sieve is used as an active component of a light hydrocarbon cracking catalyst and is used for light hydrocarbon cracking, and the diene selectivity can be improved.

The invention discloses a ceramic bearing device for thin glass processing and a ceramic supporting strip preparation method, the ceramic bearing device for thin glass processing comprises a plurality of ceramic supporting strips and a supporting frame, the ceramic supporting strips are vertically arranged, and the plurality of ceramic supporting strips are arranged in parallel; the ceramic supporting strip comprises a continuous ceramic line, and the diameter of the ceramic line is 1-2 mm. The ceramic line is provided with a plurality of first arc-shaped ceramic line segments, every two adjacent first arc-shaped ceramic line segments are connected through a connecting part, and each connecting part comprises a horizontal ceramic line segment or a second arc-shaped ceramic line segment. The first arc-shaped ceramic line segment is of an arc-shaped structure; the arc-shaped ceramic line segment is of an arc-shaped structure; the ceramic support strip is prepared by integral forming; the prepared ultra-thin glass bearing device is resistant to acid and alkali corrosion and stable at high temperature, and the supporting strips used for bearing ultra-thin glass are integrally formed and long in service life.

The invention relates to a tin plating solution, in particular to a neutral tin plating solution for electroplating a terminal electrode of a micro component and a preparation method of the neutral tin plating solution. Methanesulfonic acid as a conductive salt; hydroquinone as an antioxidant; a divalent tin ion; and salts or chelates of hydroxycarboxylic acids and cyclic ester compounds thereof as complexing agents. Compared with the prior art, the method has the main advantages that the method is green and environment-friendly, the wastewater treatment process is simple, the tin plating solution has good dispersing capacity, a plating layer with the uniform thickness can be obtained on the surface of a workpiece, and the obtained plating layer is compact, uniform, small in grain size and free of pores.

The invention discloses a zinc tellurium alloy target material and a preparation method thereof, relates to the field of semiconductor target material preparation, and aims to solve the problem of how to prepare a zinc telluride target material with uniform particle size, and the technical scheme is as follows: 1) selecting a Zn ingot with the purity of 99.99% and a Te ingot with the purity of 99.99% as raw materials for proportioning; (2) weighing and proportioning the Zn ingot and the Te ingot, and then adding the Zn ingot and the Te ingot into a vacuum smelting furnace for mixed smelting to obtain a blank; (3) the pretreated blank is added into gas atomization granulation equipment for granulation; (4) powder particles obtained through gas atomization granulation are put into a ball milling tank to be subjected to ball milling, and powder is obtained; the invention discloses a zinc tellurium alloy target material and a preparation method thereof.The zinc tellurium alloy target material and the preparation method thereof have the advantages that the zinc tellurium alloy target material is low in gas content, uniform in microstructure and fine in grain size.

The utility model belongs to the technical field and discloses an electrolyte-resistant composite aluminum foil, a current collector and a battery. The electrolyte-resistant composite aluminum foil comprises a flexible base material, a plurality of conductive layers are symmetrically arranged on the upper side and the lower side of the flexible base material, and a barrier layer is arranged between every two adjacent conductive layers. A plurality of conducting layers are symmetrically arranged on the upper side and the lower side of a flexible base material, and a blocking layer is arranged between every two adjacent conducting layers; the barrier layer can break grain growth, reduce stress concentration and defects, increase the compactness of the film layer, improve the overall weather resistance of the film layer, prolong the service life of the composite aluminum foil, and indirectly prolong the cycle life of the battery.

The invention provides a preparation method of an iron-based coating, which comprises the following steps: S1) respectively arranging a laser head and an induction coil on two sides of a sample to be processed, spraying iron-based alloy powder from the laser head, and starting laser cladding from one side of the sample to be processed by the laser head; s2) after the laser head advances 4-6 cm on the surface of the to-be-processed sample, starting the induction coil until the end; and S3) tempering the sample obtained in the step S2). The invention further provides a preparation device of the iron-based coating. According to the preparation method of the iron-based coating, preparation of the iron-based coating is achieved through combination of laser cladding and induction cladding, the problems that the coating is prone to cracking and poor in compactness due to independent laser cladding are solved, generation of defects such as pores and cracks of the coating can be greatly reduced, and the wear resistance and corrosion resistance of the iron-based coating are improved.

The invention relates to a water mist cooling process for aluminum alloy spoke machining, and relates to the field of wheel machining. The water mist cooling process for aluminum alloy spoke machining comprises the steps that smelting is conducted, specifically, aluminum alloy ingredients with a preset proportion are added into a smelting furnace and heated to be molten, and molten aluminum is formed; refining: nitrogen is introduced into the molten aluminum for rotary degassing refining treatment, and first casting liquid is formed; refining, specifically, a refiner and a modifier are added into the first casting liquid, and second casting liquid is formed through deslagging treatment; casting is conducted, specifically, the second casting liquid is pumped into a low-pressure casting mold to form a casting blank; and cooling is conducted, specifically, the low-pressure casting mold is subjected to water mist cooling, and a casting finished product is formed. According to the method, rapid solidification of the spoke casting can be achieved, the casting period is shortened, the production efficiency is improved, and meanwhile the casting is small in grain, more compact in microstructure and higher in performance strength.

The application provides a preparation method of a steel-aluminum alloy with a prefabricated framework, and belongs to the technical field of non-ferrous metal preparation. According to the characteristics of stainless steel and aluminum alloy materials, a stainless steel framework structure with added boron (B) elements is prepared by using a selective laser additive manufacturing technology. The stainless steel framework adopts a designed 'arch bridge' structure, has excellent compressive strength, and the 'arch bridge' structure design is flexible. The weight is reduced without reducing the strength, and the addition of boron elements can improve the strength of the stainless steel framework. An aluminum alloy melt is filled into the stainless steel 'arch bridge' shaped framework by a casting method. In the casting process, an ultrasonic wave is applied to reduce defects in the casting process, refine aluminum alloy grains, improve the heterogeneous interface bonding strength of steel and aluminum, reduce internal residual stress, and prepare a composite material of an aluminum alloy filled stainless steel framework with excellent performance and an 'arch bridge' microstructure.

The invention discloses a low-frequency and pulse combined electromagnetic continuous casting method, which belongs to the technical field of metal material preparation and processing, in the processes of semi-continuous casting, horizontal continuous casting and vertical continuous casting, n magnet exciting coils are placed in a crystallizer jacket in the direction parallel to the central axis of a cast ingot, n is greater than or equal to 2, and the n magnet exciting coils are divided into two groups; two groups of different current and voltage are respectively output by using power supply control systems of two sets of control circuits and are applied to two groups of excitation coils; one set of circuit system outputs low-frequency alternating-current voltage and periodic change current to generate a low-frequency alternating-current electromagnetic signal, and the other set of circuit system outputs a group of square-wave pulse voltage and zigzag pulse current to generate a pulse oscillation magnetic field; different magnetic field combinations generated by the two sets of magnet exciting coils act on a pasty area of metal melt and metal. For different kinds of metal or alloy, in the casting process, the electromagnetic utilization rate is increased, grains are refined, and the ingot casting quality is improved.

The application provides a battery aluminum foil and a preparation method thereof, and relates to the technical field of battery aluminum foils.The preparation method is as follows: S1, hot rolling of an aluminum foil blank to obtain an aluminum foil intermediate body with a thickness of 3.5-4.1 mm; S2, multi-pass cold rolling of the aluminum foil intermediate body under ultrasonic vibration system using lubricating oil to obtain a foil rolling blank with a thickness of 0.35-0.45 mm, wherein, when the cold rolling is rolled to an intermediate pass thickness of 0.6-0.9 mm, complete recrystallization annealing is carried out under nitrogen protection, and the annealing temperature is 400-450 DEG C; S3, foil rolling of the foil rolling blank to obtain an aluminum foil with a thickness of 0.01-0.015 mm; and S4, corona treatment of the aluminum foil, coating of modified paint on the surface of the aluminum foil, drying, and obtaining of the battery aluminum foil.The battery aluminum foil has excellent electrochemical performance, high strength, and high surface roughness.

The invention discloses a high-performance copper-chromium-zirconium alloy cast rod and wire and a preparation method thereof, and relates to the field of metal material processing. The alloy casting rod comprises Cr, Zr, R and the balance copper and inevitable impurities, the R is Mg and / or Zn and other elements, cathode copper, a copper-chromium intermediate alloy, a copper-zirconium intermediate alloy, a copper-magnesium intermediate alloy and / or a copper-zinc intermediate alloy are completely melted and then subjected to heat preservation treatment, then vacuum down-drawing continuous casting is conducted, traction is conducted in the mode of'traction, stopping and withdrawing ', and the casting rod is obtained. The casting rod is produced through vacuum down-drawing continuous casting, high-quality and industrial production can be achieved, the viscosity of molten copper is effectively improved by adding elements such as Mg or Zn, the resistance of copper alloy down-drawing continuous casting is reduced, meanwhile, the situation that the casting rod is broken or hot cracks are generated in the down-drawing process is avoided in cooperation with the traction mode of'traction + stop + retreat ', and the production efficiency is improved. The finally prepared casting rod is uniform in structure and small in grain, good mechanical performance and machinability are obtained, and the application performance requirement is met.

This invention provides a method for producing lubricating oil base oil from heavy feedstock and the resulting lubricating oil base oil. The method includes: cutting the heavy feedstock to obtain a light component, a middle fraction, and a bottom wax; wherein the boiling point ranges of the light component, the middle fraction, and the bottom wax are 170-300℃, 300-500℃, and >500℃, respectively; subjecting the bottom wax to a first isomerization reaction under the catalysis of a first isomerization catalyst to obtain a first isomerization product; subjecting the first isomerization product and the middle fraction to a second isomerization reaction under the catalysis of a second isomerization catalyst to obtain a second isomerization product; subjecting the second isomerization product to hydrorefining; and then fractionating the obtained refined product to obtain the lubricating oil base oil. The lubricating oil base oil produced by this method has high yield, low pour point, low cloud point, and high viscosity index, making it a high-quality lubricating oil base oil.

The invention provides a nano ZSM-5 molecular sieve and a preparation method thereof. The preparation method comprises the following steps: mixing a first silicon source, a first aluminum source, inorganic alkali, water and amorphous molecular sieve pre-crystallization liquid, and aging to obtain a first raw material mixture; adding a second silicon source into the first raw material mixture to obtain a second raw material mixture, crystallizing, filtering, washing, drying and roasting to obtain the nano ZSM-5 molecular sieve, the second silicon source comprises white carbon black. The invention also provides the nano ZSM-5 molecular sieve obtained by the preparation method. The nano ZSM-5 molecular sieve provided by the invention has the characteristics of small crystal grain, large specific surface area and abundant mesopores and macropores.

The invention discloses a high-strength aluminum alloy material for automobile calipers and a production process of the high-strength aluminum alloy material. The high-strength aluminum alloy material comprises 10.36%-11.58% of Si, 1.23%-2.14% of Fe, 1.05%-1.17% of Cu, 0.32%-0.35% of RE, 0.18%-0.21% of Sr, 3.55%-3.85% of composite strengthening powder and the balance pure aluminum. The prepared high-strength aluminum alloy material for the automobile calipers is good in mechanical performance and high in strength and has excellent high-temperature resistance and good heat conduction capacity, the composite strengthening powder is added into the formula of the aluminum alloy material, crystal grains of the aluminum alloy material are refined through titanium boride in the composite strengthening powder, and the high-strength aluminum alloy material is obtained. Silicon phase grains in the aluminum alloy material are refined through the graphene nanosheets, the influence of the high silicon content on the aluminum alloy material is reduced, and the mechanical strength and the high temperature resistance of the aluminum alloy material are improved.

The invention relates to the technical field of water-based zinc ion batteries, in particular to a water-based composite electrolyte containing a charge separation inner salt additive and a preparation method and application of the water-based composite electrolyte. An inner salt additive containing charge separation is added into a zinc ion electrolyte to prepare a water-based composite electrolyte, and the water-based composite electrolyte is applied to a zinc battery. The inner salt additive for charge separation changes the solvation structure of zinc ions through the chelation with the zinc ions, and attracts the zinc negative electrode through the charge effect to enrich on the surface of the zinc negative electrode to generate a solid electrolyte interface in situ, so that the diffusion mode of the zinc ions at the interface of the zinc negative electrode is changed from two-dimensional diffusion to three-dimensional diffusion; the formation and growth of zinc dendrites are inhibited, and the coulombic efficiency of the battery and the cycle performance of the battery under high current are greatly improved.

The invention discloses a continuous casting process for reducing surface rolling cracks generated by hot charging of a 20CrMo steel continuous casting billet, which comprises the following steps of: passing 20CrMo molten steel meeting requirements through a crystallizer to obtain the continuous casting billet, and cooling the obtained continuous casting billet by stages to convert a metallographic structure on the surface layer of the continuous casting billet from austenite into bainite and martensite, and a grain boundary AlN phase is controlled to be separated out, then the treated continuous casting billet is fed into a heating furnace to be subjected to follow-up treatment, and the 20CrMo steel continuous casting billet is obtained. The continuous casting process has the beneficial effects that the separation amount of AlN on the surface layer of the continuous casting billet can be effectively reduced through the partition surface rapid cooling process after the continuous casting billet is discharged out of the crystallizer, the appearance of grain boundary film ferrite is avoided, and the purpose of reducing hot charging surface rolling cracks is achieved. The process is easy to implement, and the rapid production rhythm can be guaranteed.

The invention discloses a method for preparing composite ferric sodium pyrophosphate by sulfur cycle, which comprises the following steps: S1, preparation of composite ferric sodium pyrophosphate: mixing ferrous sulfate, a sodium source, a phosphorus source and a dispersing agent by a wet process, spray-drying to obtain a precursor, and calcining at high temperature under a protective atmosphere to obtain the composite ferric sodium pyrophosphate; s2, tail gas recovery and conversion: sulfur-containing tail gas generated in the high-temperature calcination process of the precursor and air pass through a multi-layer vanadium pentoxide catalyst, and temperature control reaction is performed to convert SO2 into SO3, so that SO3 tail gas is obtained; s3, SO3 tail gas collection and conversion: SO3 tail gas is transferred into a sulfuric acid collector through temperature control of a heat exchanger, so that SO3 and H2O are cooled and converted into a sulfuric acid solution; and S4, preparation of ferrous sulfate: adding an iron source into a sulfuric acid solution, carrying out heating reaction, carrying out solid-liquid separation, cooling, and adding a reducing agent for reaction to obtain the ferrous sulfate used in the step S1. The preparation method has the characteristics of low cost, high reversible specific capacity and environment friendliness.

This invention relates to high-temperature, high-strength zirconium-hafnium yttrium solid solution oxide continuous fibers, their preparation methods, and applications. In these continuous fibers, hafnium oxide replaces some zirconium oxide sites in a yttrium-stabilized zirconium oxide lattice, forming a single solid solution phase containing zirconium, hafnium, yttrium, and oxygen. The three metal elements are randomly distributed in the lattice, and the phase is either tetragonal or cubic. Using poly(zirconium acetylacetonate) and poly(hafnium acetylacetonate) as the zirconium and hafnium sources respectively, a spinneret is prepared with the addition of a stabilizer. Spinning is then performed to obtain precursor continuous fibers. After vapor pressure desorption and medium-temperature steam treatment, primary crystallized continuous fibers are obtained, followed by high-temperature ultrafast heat treatment to obtain the final product. The zirconium-hafnium yttrium solid solution oxide continuous fibers of this invention exhibit good high-temperature stability. After being held at 1500 °C for 120 min, they still possess high mechanical strength and excellent flexibility, with an average tensile strength of over 1.0 GPa for each filament. They can be used as high-temperature structural reinforcement materials and high-temperature flexible thermal insulation materials.

The invention provides a high-hardness corrosion-resistant zirconium-titanium alloy and a preparation method thereof, and relates to the technical field of alloy materials, the alloy is Zr, Ti, Al and V alloy, and the mass ratio of Zr to Ti to Al to V is 47: 45: 5: 3. The preparation method comprises the following steps: S1, preparing a raw material electrode by using an alloy raw material; s2, smelting a raw material electrode; s3, performing hot forging to obtain a forged rod-shaped alloy; and S4, performing high-pressure solidification on the alloy at a certain temperature and pressure. The general hardness of the high-hardness zirconium-titanium alloy prepared through the preparation method ranges from 462.4 HV to 859.08 HV, the hardness of the alloy obtained through the optimal preparation condition is 800 HV or above, the corrosion resistance is greatly improved, and the excellent performance of high hardness and high corrosion resistance is achieved.

The invention relates to a low-dielectric-loss giant dielectric ceramic and a preparation method thereof. The preparation method comprises the following steps: ball milling: putting perovskite giant dielectric ceramic powder, a dispersion medium and a ball milling medium into a ball milling tank for ball milling; granulation: adding a polyvinyl alcohol aqueous solution into the slurry for granulation; aging: adding deionized water, uniformly mixing, and aging to obtain mixed powder; dry pressing molding: pressing the mixed powder into flaky ceramic with a certain thickness by adopting a grinding tool and a pressing machine; cold isostatic pressing molding: carrying out cold isostatic pressing post-treatment on the flaky ceramic, placing a wafer in air for standing, and then drying; and sintering: transferring the flaky ceramic into an oscillation sintering furnace, applying oscillation pressure and large current in different sintering stages by using a large-current oscillation pressure sintering process, and cooling to obtain the perovskite giant dielectric ceramic. The perovskite giant dielectric ceramic obtained by the preparation method has the advantages of high dielectric constant and low dielectric loss.

The application belongs to the technical field of aluminum alloy processing, and particularly relates to a high-strength and high-toughness 7-series aluminum alloy plate with equiaxed crystal structure and a short-process preparation method thereof. The application improves the comprehensive performance of the aluminum alloy by combining extrusion, cold rolling and heat treatment, and can effectively solve the problems of grain deformation, anisotropy of the structure and mechanical properties of the 7-series aluminum alloy plate in the production process. The 7-series aluminum alloy plate is prepared from an aluminum alloy ingot, and the aluminum alloy ingot is composed of the following components in percentage by mass: Zn: 4.5-6.8%, Mg: 1.8-3.0%, Cu: 0.30-0.70%, Mn: 0.30-0.70%, Zr: 0.10-0.20%, Yb: 0.10-0.40%, and the rest is Al, wherein the mass fraction ratio of Zn and Mg is Zn / Mg: (2.7-3.1):1. The application adopts a short-process high-efficiency preparation method, eliminates the original fibrous structure, improves the anisotropy of the mechanical properties of the material, and obtains the 7-series aluminum alloy plate with equiaxed crystal structure, a tensile strength greater than 550 MPa, an elongation after fracture greater than 12% and other excellent comprehensive properties.