2156 results about "Crystallite" patented technology

The invention provides a preparation method of laser cladding heterostructure stainless steel. According to the method, dried stainless steel pre-alloyed powder is subjected to laser melting deposition to form heterostructure stainless steel alloy with cross deposition of coarse grains and fine grains; the grain size of the fine crystal is 3-6 [mu] m, and the structure of the fine crystal layer is an equiaxed structure; the grain size of the coarse crystal is 20-50 [mu] m, and the structure of the coarse crystal layer is a columnar crystal formed along the Z axis. According to the method, the specific coarse grain / fine grain cross deposition heterostructure is presented in the stainless steel by changing the deposition layer process parameters and the scanning path, the material strength is improved while the material ductility is guaranteed, and the alloy has the excellent mechanical property.

The invention discloses a high-oxygen-storage zirconium solid solution material and a preparation method, and belongs to the technical field of rare earth catalytic materials, and the method comprises the following steps: precursor preparation, ultrasonic dispersion, double-gradient precipitation, ultrasonic aging, solid-liquid separation, three-section roasting and furnace cooling. Through the synergistic effect of double-gradient precipitation and ultrasonic aging, coarse grains and non-uniform particle size distribution are avoided, and the material is not prone to abnormal growth of the grains and structural collapse in long-term high-temperature service. Meanwhile, according to the gradient roasting process, through step-by-step regulation and control of crystal densification and crystal lattice reconstruction, separation of a fluorite phase and a pyrochlore phase easily occurring in traditional low-temperature single-section roasting is reduced, a stable crystal phase structure is maintained, it is ensured that the material can still keep sufficient active surface and pore channel structures under the working conditions of high temperature and thermal shock alternation, and the performance of the material is improved. The oxygen storage capacity and the long-term durability of the catalyst carrier are obviously improved.

The invention relates to the technical field of additive manufacturing, and discloses an additive manufacturing hot-crack-free precipitation strengthening high-temperature alloy and a preparation method thereof.The method comprises the steps that a laying layer is divided into a plurality of parallel scanning strips according to the preset translation direction and the scanning strip interval, strip type scanning is conducted in a laser autorotation and translation motion coupling mode, and the high-temperature alloy is obtained; molten pool disturbance is remarkably enhanced, periodic shear fracture of the tip of dendritic crystal is achieved, epitaxial growth of columnar crystal is broken, grain equiaxalization is achieved, and anisotropy is weakened; in addition, laser scanning is a high-speed scanning strategy with the translation speed larger than or equal to 1500 mm / s, a shallow molten pool is formed through regulation and control of the high scanning speed, surface tension in the shallow molten pool is utilized, convection in the molten pool is enhanced, dendritic crystals are refined, columnar crystals in the high-temperature alloy are further reduced, and anisotropy of mechanical properties is remarkably eliminated; and the transverse strength and creep resistance at high temperature are improved. The isometric crystals can effectively prevent cracks from expanding in the orientation direction of the columnar crystals, and the fatigue life and the damage tolerance are remarkably prolonged.

An additive manufacturing method based on micro-selective laser melting technology. By using a spot size of 30 μm or less, a metal powder layer thickness of 10 μm or less and ultrafine metal powders having a D90 particle size of 30 μm or less, and in combination with the control of a scanning laser power, a scanning rate, a linear energy density and a volumetric energy density within specific ranges, the method can print complex-structured metal parts having extremely high resolutions and surface smoothness, and can obtain a high-density internal structure of a component even under a relatively low energy density or power condition, thereby effectively protecting an optical system. Moreover, a printed component exhibits a defect-free microstructure, and has excellent electrical properties, thermal properties and mechanical properties. Particularly, ultrafine grains and a high dislocation density provide superior mechanical properties compared to conventional manufacturing materials. An infrared laser device can be used, thereby achieving low costs.

The invention discloses a heat treatment method of an iron-nickel-based high-temperature alloy, which solves the contradiction between stress relief annealing and performance maintenance through four-step temperature coordinated regulation and control: in the first step, MC type carbide is dissolved through solid solution, segregation is eliminated, and excessive growth of crystal grains is avoided; in the second step, roughening of M23C6 type carbides is inhibited through solid solution, and formation of fine and uniform carbides on grain boundaries is promoted so as to strengthen the grain boundaries; in the third step, the residual stress is reduced through stress relief annealing, and meanwhile grain boundary carbide growth and abnormal grain growth are avoided; and in the fourth step, uniform and stable precipitation of a gamma'phase is promoted through aging, the nanometer size and the high volume fraction are maintained, and coarsening is avoided. Through precise temperature connection, the residual stress is effectively reduced, grain growth, structure nonuniformity or performance degradation caused by traditional annealing are avoided, and finally the application requirement of the superhigh-temperature steam environment at the temperature of 650 DEG C or above is met on the premise that the mechanical property and the corrosion resistance are guaranteed.

The invention relates to the technical field of softened water treatment devices, in particular to an induced crystallization granulation fluidized bed softened water treatment device. Comprising a cylinder, a stainless steel cathode layer is arranged on the inner side of the cylinder, the stainless steel cathode layer is electrically connected with a negative electrode of a power supply, an excitation system is mounted on the cylinder, a vertical vibration frame capable of vertically reciprocating is connected to the excitation system, a translation frame is slidably connected to the vertical vibration frame, and a synchronizing system for driving the vertical vibration frame and the translation frame to synchronously displace is arranged on the vertical vibration frame. The synchronous system is in transmission connection with a transmission shaft capable of alternately rotating forwards and backwards, a micro-filtration cylinder is rotationally mounted on the translation frame, an insulating shaft is rotationally mounted in the micro-filtration cylinder, the micro-filtration cylinder and the insulating shaft are driven by the transmission shaft, a plurality of guide rings are mounted on the micro-filtration cylinder, and an anode bar slides on the insulating shaft. According to the device, grain fluidization is strengthened through synchronous multi-dimensional excitation, the problem of local reaction dead angles is solved, the problems that a traditional device is low in crystallization efficiency and uneven in particle size are effectively solved, and the stability of grain settling separation is guaranteed.

The invention discloses a heat-resistant aluminum alloy material and a preparation method and application thereof, and belongs to the technical field of additive manufacturing aluminum alloy materials. The heat-resistant aluminum alloy material comprises the following components in percentage by mass: 0.5-6% of Fe, 0.5-6% of Cr, 0.5-3% of Ti, less than or equal to 2% but not equal to 0 of Mn, less than or equal to 2% but not equal to 0 of Sc, less than or equal to 2% but not equal to 0 of Zr and the balance of Al and inevitable impurities. By optimizing the component proportion, the preparation method and the like, in the microstructure of the heat-resistant aluminum alloy material, the interior of the heat-resistant aluminum alloy material is of a bimodal grain structure, the boundary of a molten pool is mainly isometric crystals, the center of the molten pool is columnar crystals, and an icosahedron nanometer quasi-crystal phase and an intermetallic compound strengthening phase are further distributed on the boundary of the molten pool and the center of the molten pool in a dispersed mode; the problems that when a traditional aluminum alloy material is used for additive manufacturing forming, hot cracks or macroscopic cracks occur, and the mechanical property of a formed product is poor are fundamentally solved.

The invention relates to a preparation method of an etching-resistant and wear-resistant Y2O3-AlxOy composite coating. The preparation method comprises the following steps: carrying out ultrasonic cleaning on a corrosion-resistant matrix; performing plasma bombardment cleaning activation on the surface of the corrosion-resistant matrix; a Y2O3 coating and an AlxOy coating are alternately deposited on a corrosion-resistant base body in a double-target magnetron sputtering mode to form the Y2O3-AlxOy composite coating, the sputtering power of a Y target is larger than that of an Al target, and the ratio of x to y in the AlxOy coating is larger than 1. According to the method, the amorphous AlxOy coating dominated by the metal state is introduced into the Y2O3 coating, growth of Y2O3 columnar crystals is continuously broken, crystal grains are refined, formation of intergranular easy-to-etch point locations is inhibited, and an yttrium aluminum oxide composite strengthening phase is formed at an interface, so that plasma etching resistance is improved; the thickness of a single-layer coating in the composite coating is very thin; under the action of growth stress, the structure of the coating presents a wave-shaped microstructure and a soft and hard alternate mechanical structure, and the soft and hard alternate mechanical structure is beneficial to inhibiting generation of transverse cracks, guiding friction crack level expansion, prolonging the friction life of the coating and reducing the wear rate.

The invention discloses a welding thermal stress simulation method, device, equipment and medium based on a crystal plasticity finite element, and relates to the technical field of welding thermal stress finite element simulation. The method comprises the steps that a sample is prepared according to a specific multi-phase metal material, and phase distribution and crystal orientation information of a two-dimensional plane of the material are obtained through a metallographic experiment; and a three-dimensional multi-grain model is constructed based on the two-dimensional information. According to the method, a crystal plastic constitutive model is adopted to describe the flowing behavior of the material at high temperature, crystal slippage and polycrystal interaction are considered, the influence on the material performance is reflected from the microstructure evolution level, and the problem that the influence on the macroscopic mechanical performance of a microstructure is difficult to capture in welding multiphase metal material simulation is solved; two-dimensional representation is obtained through a metallographic experiment, the Young modulus and rigidity matrix parameters are accurately calculated by combining forward stretching and shear simulation, the rigidity matrix precision is improved, a temperature field area is divided, stress evolution and residual stress are calculated by combining a thermal-elastic-plastic model, and the welding thermal stress calculation precision is improved.

The invention discloses a heat treatment method for optimizing a gear steel structure and refining grains, and belongs to the technical field of heat treatment process control. The method is particularly suitable for a production scene of cold forging gear parts such as three pin shafts; according to the method, a pre-normalizing or annealing heat treatment process with specific parameters is added after cold forging forming and before carburizing, so that an AlN precipitated phase in the steel forms segregation again at a grain boundary, the grain boundary is effectively pinned, and austenite grain growth is inhibited, and therefore the phenomenon of mixed crystals is avoided, the structure is refined, and the fatigue performance is improved. Experiments prove that after normalizing pretreatment at the temperature of 900 DEG C or above or annealing pretreatment at the temperature of 720 DEG C is adopted, the original cold forging mixed crystal area with the grain size of 0-4 grade can be increased to 7 grade or above, grains are uniform and compact, and the structure property is remarkably improved. The process parameters are clear, the flow is controllable, and the method is suitable for optimization and application of the batch gear steel heat treatment process.

The invention discloses a multi-scale simulation method for a thermal compression deformation behavior of TC4 titanium alloy, and belongs to the field of metal material processing simulation. Comprising the following steps: 1, carrying out thermal compression experiments at different temperatures to obtain a deformed sample; 2, analyzing the grain orientation, orientation difference angle and texture evolution of the sample by using an electron back scattering diffraction technology; 3, constructing a crystal plasticity finite element model, and simulating a polycrystalline deformation process; 4, constructing a molecular dynamics model, and simulating phase change and dislocation evolution in thermal compression and cooling processes; and 5, based on a multi-scale simulation result, hot working parameters are optimized, dynamic recrystallization and a beta-to-alpha phase change path are regulated and controlled, and grain refinement and performance homogenization are achieved. The invention discloses a correlation mechanism of the microstructure and the mechanical property in TC4 titanium alloy thermal compression deformation, and provides a theoretical basis for optimization of a thermal processing technology of a high-performance titanium alloy component in the aerospace field.

The invention discloses an electroplating process method for preparing a deep-etching thick metal mask, and belongs to the technical field of micro electro mechanical system electroplating processes. Comprising the following steps: firstly, carrying out photoetching and patterning on the surface of a wafer by using positive photoresist; then, carrying out seed layer sputtering on the wafer subjected to pattern photoetching, and forming a to-be-electroplated region with a preset pattern through a stripping process; then, photoetching is carried out on the to-be-electroplated area through negative photoresist, and a thick photoresist layer with the thickness larger than that of a preset metal coating is formed; and finally, the electroplating area is electroplated, and the metal coating with the preset thickness is obtained. According to the method, the negative photoresist process is adopted, so that the transverse growth of the metal coating is effectively inhibited, the perpendicularity of the side wall of the metal coating is improved, and meanwhile, the damage to the surface of the wafer when the seed layer in the non-electroplating area is removed is avoided. The problems that mushroom-shaped protrusions are easily formed on the edge of a plating layer, crystal grains are coarsened and the like in the electroplating process of an existing electroplating method are solved.

A vacuum insulating panel includes first and second substrates (e.g., glass substrates), a hermetic edge seal, a pump-out port, and spacers sandwiched between at least the two substrates. The gap between the substrates may be at a pressure less than atmospheric pressure to provide insulating properties. The panel may include a getter. The getter may be laser activated in a manner which causes the getter to transform and realize a Ti—Al—V phase (e.g., Al3V0.333Ti0.667) of crystallite material. The getter may be a thin film getter and / or may be elongated in shape.

The invention relates to a preparation method and application of a composite piezoelectric catalytic material NaNbO3-coated BiFeO3 for rapidly degrading antibiotics, NaNbO3 is flaky crystal grains with [001] crystallographic orientation prepared by a two-step molten salt method, and BiFeO3 is micro-nano particles prepared by a coprecipitation method. Composite micro-nano BiFeO3 powder and [001] oriented NaNbO3 flaky grains form a heterojunction, conversion of mechanical energy and electric energy of the material is achieved under the ultrasonic vibration condition, inductive charges are generated on the surface of the material, and photon-generated carriers move reversely under driving of a built-in electric field. According to the invention, the piezoelectric catalytic degradation capability of the BiFeO3 and NaNbO3 composite piezoelectric catalytic materials with different proportions on four antibiotics, namely oxytetracycline, levofloxacin, carbamazepine and paracetamol in different time periods is researched. When the mass ratio of the BiFeO3 to the NaNbO3 composite material is 1: 3, the oxytetracycline degradation rate within 30 min can reach 78.2%, the oxytetracycline degradation rate within 120 min can reach 91.8%, and the piezoelectric electro-catalysis characteristic is rapid and efficient. The method disclosed by the invention has important significance in developing a high-efficiency piezoelectric catalyst for degrading antibiotics.

The invention provides a nickel-based rare earth composite powder material for high-speed laser cladding and a preparation method of a nickel-based rare earth composite coating, and relates to the technical field of laser cladding and metal surface modification. The nickel-based rare earth composite coating takes Inconel 625 nickel-based alloy as a matrix phase material; a trace amount of rare earth oxide Y2O3 is introduced into a powder system to serve as a second phase enhancing component, and the material is prepared and formed at a time under the condition of a high-speed laser cladding process; in the high-speed laser cladding process, due to high scanning speed, low heat input per unit length and high cooling rate, metal liquid in a molten pool has the characteristic of rapid solidification; the rare earth oxide Y2O3 can stably exist in a molten pool, the particle surface of the rare earth oxide Y2O3 provides a large number of heterogeneous nucleation cores for the alloy solidification process, meanwhile, grain growth is restrained through the grain boundary pinning effect, and therefore the solidification structure form of the nickel-based cladding coating is remarkably improved.

A method for generating a training dataset for determining grain boundaries and minerals in a thin section of a rock sample, includes receiving the thin section of the rock sample, generating optical images of the thin section with an optical tool, generating mineral phase images of the thin section with an electron microscopy tool, computing first and second pseudo-images based on different features extracted from the optical images, generating the training dataset based on (1) the optical images, (2) the mineral phase images, and (3) the pseudo-images, and training a single deep neural network, DNN, based on the training dataset to simultaneously determine a mineral type and grain boundaries in the thin section of the rock sample.

The invention belongs to the technical field of zirconite porous ceramics, and discloses a method for preparing high-strength zirconite porous ceramics by a foaming injection-coagulation method, which is characterized in that zirconite powder, yttrium oxide powder and manganese oxide powder are used as raw materials, and the foaming injection-coagulation method is adopted to prepare the zirconite porous ceramics. The zirconite porous ceramic is obtained through the steps of syrup solution preparation, ceramic powder premixing, ceramic slurry preparation, injection molding gelling, sintering treatment and the like. The foaming gel casting method is adopted, so that the porosity of the zirconite porous ceramic can be effectively increased, and the heat radiation transmission efficiency is reduced; saccharide is used as a solution medium instead of water, so that the sintering surface is increased and the strength of the porous ceramic is improved; the manganese oxide and the yttrium oxide are added, so that the merging and growing process among zirconite crystal grains is accelerated, the crystal form of zirconium oxide is stabilized at high temperature, cracks caused by crystal form transformation are avoided, the strength of the zirconite porous ceramic is further improved, and the prepared zirconite porous ceramic is stable in high-temperature performance, high in strength and low in heat conductivity coefficient.

A steel sheet having a tensile strength (TS) of 780 MPa or more and less than 1180 MPa, high LME resistance, and good weld fatigue properties. The steel sheet has a specific chemical composition and a specific steel microstructure. Crystal grains containing an oxide of Si and / or Mn in a region within 4.9 μm in a thickness direction from a surface of the steel sheet have an average grain size in the range of 3 to 10 μm, the lowest Si concentration LSi and the lowest Mn concentration LMn in the region within 4.9 μm in the thickness direction from the surface of the steel sheet and a Si concentration TSi and a Mn concentration TMn at a quarter thickness position of the steel sheet satisfy a specified formula.

To provide an Fe-Ni-Cr alloy that can suppress intergranular cracking (nitriding resistance) and also inhibit the formation of red scale (oxidation resistance) even in a gas atmosphere containing nitrogen and water vapor, such as ammonia combustion gas, at a medium-high temperature range of 500 to 700°C.SOLUTION: The present invention relates to an Fe-Ni-Cr alloy that has a predetermined component composition, a nitriding resistance index of 81 or higher, and 3.0 or more of fine crystalline grains with a grain size of 0.5 μm or less present in the plate thickness direction in the alloy surface layer. The Fe-Ni-Cr alloy is obtained by introducing strain (transformation) on the surface of the alloy material by polishing or the like, then performing heat treatment, and generating fine crystalline grains using the introduced strain (transformation) as a driving force. Nitriding resistance index: Cr+3Ni-10Mo≥81.SELECTED DRAWING: None

The invention discloses a low-glass-phase fused zirconia corundum brick with a special structure and a preparation method thereof. The fused zirconia corundum brick comprises the following chemical components in percentage by mass: greater than or equal to 32.5% of ZrO2, less than or equal to 15% of SiO2, less than or equal to 1.4% of K2O + Na2O + CaO + MgO, and the balance of Al2O3 and inevitable impurities. In addition, the content of a glass phase of the fused zirconia corundum brick is smaller than or equal to 20%, and the glass phase is divided into discontinuous blocky areas by a corundum phase in a microstructure. By optimizing the raw material ratio and the casting process, a unique microstructure is formed in the fused zirconia corundum brick, the glass phase of the fused zirconia corundum brick is uniformly divided into discontinuous areas by a dendritic corundum phase, coarse baddeleyite grains are accompanied around the discontinuous areas, the viscosity of the glass phase is remarkably improved by the structure, the flow connectivity of the fused zirconia corundum brick is effectively limited, and the fused zirconia corundum brick has good heat resistance. The product has excellent characteristics of high glass phase exudation temperature and low exudation amount, the product is particularly suitable for flame space parts of the glass melting furnace, pollution to molten glass can be avoided due to the low glass phase exudation characteristic of the product, the quality of the glass product can be improved, and the service life of the furnace can be prolonged.

The invention relates to the technical field of dielectric ceramic powder preparation processes, in particular to a multilayer ceramic capacitor, high-activity nano barium titanate powder for the multilayer ceramic capacitor and a preparation method of the high-activity nano barium titanate powder, and the method comprises the following steps: (1) reacting soluble barium salt with a precipitator to obtain barium carbonate precursor particles with high specific surface area; (2) uniformly coating the surfaces of the barium carbonate precursor particles with nano titanium dioxide particles by using a supercritical fluid flash evaporation technology to form a composite precursor; and (3) carrying out solid-phase synthesis reaction on the composite precursor, and sintering to obtain the nano barium titanate powder. Through the synergistic effect of two means of high-activity precursor preparation and nanoscale uniform coating, the composite precursor with extremely high specific surface area, surface energy and microcosmic uniformity is prepared, the thermal sintering temperature is effectively reduced, abnormal growth of crystal grains and lattice distortion are restrained, and the preparation method has the advantages that the preparation process is simple, and the preparation cost is low. The tetragonality of the nano barium titanate powder is obviously improved.

The invention provides a continuous annealing process method for cooperatively regulating and controlling the shape of an ultrathin and wide precise foil, and relates to the technical field of advanced material processing frontier. According to the continuous annealing process method for synergistically regulating and controlling the shape of the ultrathin and wide precise foil, micron-sized precise foils with different marks, the specification of 0.02-0.2 mm and the width of more than 600mm are selected for continuous annealing, and the preparation process comprises the following steps: putting a cold-rolled and cleaned ultrathin and wide foil coiled material into a continuous annealing furnace for annealing treatment, and the method can be suitable for regulating and controlling the structure properties and the plate shapes of various ultrathin precise foils. The method can effectively control the abnormal growth of crystal grains, realizes the fine grain structure of the foil, improves the surface quality and the mechanical property of the ultrathin precise foil, fills the technical defects of the plate shape consistency and the structure property of the ultrathin and wide precise foil after annealing, and has positive significance in promoting the development of the key technical industry in China.

The invention discloses a method for improving the oxidation resistance of nickel-based superalloy, and belongs to the technical field of metal material surface modification. Based on the high-energy transient effect of laser shock waves, the method mainly comprises the key steps of alloy surface pretreatment, laser shock peening process implementation, post-treatment and the like. Specifically, firstly, the surface of the nickel-based single crystal alloy is subjected to pretreatment such as polishing and cleaning, surface defects and pollutants are removed, and the treatment quality is guaranteed; then, according to the material characteristics and performance requirements of the nickel-based single crystal alloy, laser parameters such as laser energy, pulse width and light spot diameter are accurately set, and proper restraint layer and absorption layer materials are selected; then, high-energy pulse laser is utilized to irradiate the absorption layer, high-temperature and high-pressure plasma is induced to be generated, the plasma expands and explodes to generate strong shock waves, the shock waves act on the alloy surface, the surface material is subjected to severe plastic deformation, a residual compressive stress layer with the depth capable of reaching hundreds of micrometers is formed, meanwhile, surface grains are refined, and the microstructure is optimized; and after the strengthening treatment is completed, simple cleaning and performance detection post-treatment are carried out. Through laser shock strengthening, a special organization structure with high density and low defect density is formed on the surface of the nickel-based single crystal alloy, diffusion and invasion of oxygen atoms are effectively hindered, and the oxidation resistance of the alloy is remarkably improved. According to the method, the controllability of technological parameters is high, the strengthening effect can be accurately regulated and controlled, the treatment process is free of pollution and high in efficiency, the obtained strengthened nickel-based single crystal alloy can be widely applied to the fields such as aerospace engine hot end parts and nuclear energy equipment which have strict requirements for high-temperature oxidation resistance, the reliability of related parts is greatly improved, and the service life of the related parts is greatly prolonged.

The invention discloses a solidification melting zone thermal compensation repairing device and method for adjusting a heat source mode, and belongs to the technical field of metal part repairing. In the traditional Gaussian laser single crystal repairing process, columnar crystal orientation isometric crystal transformation can be induced due to the violent heat dissipation effect on the top of a molten pool and the component supercooling effect of the solidification front edge, new crystal grains preferentially nucleate and grow on the top of the molten pool, and the mixed crystal defect on the top of a repairing layer is caused. The scheme that annular laser is adopted as main laser, a thermal compensation auxiliary laser beam and a zoom laser beam expander are added for cooperative regulation and control is provided, the temperature gradient and the cooling speed of a molten pool are controlled by accurately adjusting a heat source energy distribution mode, the tendency of columnar crystal orientation isometric crystal transformation is restrained, and the quality of the molten pool is improved. And mixed crystal defects at the top of the repair layer are eliminated. Compared with an existing method, the method is large in process window and good in parameter adaptability; the material application range is wide, and the repairing requirements of different alloy systems can be met; equipment adjustment is simple, and industrial application is easy to achieve.

The invention relates to the technical field of ceramic manufacturing processes, and particularly discloses a preparation method of a 96 aluminum oxide ceramic substrate, which comprises the following steps: slurry preparation: carrying out ball milling treatment on high-purity aluminum oxide powder, a sintering aid, a binder, a plasticizer, an organic solvent and a dispersing agent, and fully mixing to obtain tape casting slurry; forming a green body, coating a carrier film with the tape casting slurry through a tape casting machine with a wet film which is uniform in thickness and flat in surface, and drying the carrier film through a drying box in a partitioned manner to obtain a cured green body; and sintering densification treatment: carrying out glue removal treatment on the green body, and carrying out stepped heating sintering to obtain the 96 aluminum oxide ceramic substrate. According to the 96 aluminum oxide ceramic substrate prepared by the scheme, a large number of uniform crystal cores can be formed, small crystal grains can be dissolved, large crystal grains grow at a constant speed, and the uniformity of the crystal grain size is ensured, so that scattering of phonons on a crystal boundary can be reduced, and a structural foundation is laid for improvement of heat conductivity.

The invention relates to the technical field of magnetron sputtering, and provides a preparation method of a ruthenium sputtering target material. The method comprises the following steps: sequentially carrying out hydrogen introduction reduction treatment, crushing and sieving on ruthenium powder to obtain reduced ruthenium powder; and the reduced ruthenium powder is sequentially subjected to compression molding, cold isostatic pressing treatment and sintering treatment, and the ruthenium sputtering target material is obtained. According to the method, the technical problems that the ruthenium sputtering target material is high in oxygen content and random in grain orientation in a traditional powder metallurgy process are effectively solved by combining a dual deoxidization mechanism of'hydrogen feeding reduction-hydrogen sintering 'and cooperative regulation and control of cold isostatic pressing treatment and sintering process parameters. Results of the embodiment show that the ruthenium sputtering target material prepared by the method can realize the following performance indexes: the purity is greater than or equal to 99.95%, the oxygen content is less than or equal to 20 ppm, the average grain size is less than or equal to 2 microns, the density is greater than or equal to 99%, the required specific crystallographic orientation can be stably formed, and a foundation is laid for subsequent magnetron sputtering preparation of a high-performance film.

The invention provides a perovskite solar cell, a preparation method thereof and a photovoltaic module, and the perovskite solar cell comprises a substrate, a first carrier transmission layer, a perovskite absorption layer, a second carrier transmission layer and an electrode layer which are sequentially stacked. And a nano-silver particle layer is arranged between the first carrier transport layer and the perovskite absorption layer. According to the invention, the nano-silver particle layer is used as a crystal nucleus, so that the crystallization of the perovskite absorption layer is promoted, and the high-quality perovskite thin film with large grain size and low defect density is formed; in addition, the particle surface of the nano-silver particle layer can reflect sunlight, a light trapping structure is formed, and the utilization rate of light can be remarkably improved. In conclusion, the photoelectric property of the perovskite solar cell can be effectively improved, and the perovskite solar cell has a wide application prospect.

The invention belongs to the technical field of perovskite solar cells, and particularly relates to a preparation method for improving the quality of a perovskite thin film by using a local high-temperature field, and the method comprises the steps: 1, forming a perovskite precursor thin film on an electron transmission layer; step 2, when the precursor film is in an intermediate phase or an incompletely crystallized state, placing the precursor film below a heating plate with a microstructure array, keeping a gap between a convex part of the microstructure array and the surface of the precursor film, and forming a periodically distributed local high-temperature field on the surface of the precursor film; step 3, maintaining the local high-temperature field to act for a period of time, so that the local area of the precursor film is preferentially crystallized; and 4, removing the heating plate, and uniformly annealing the precursor film. According to the method, a local high-temperature field is applied to induce a hot spot region to preferentially nucleate, abnormal growth and Ostwald ripening of crystal grains are inhibited, and the large-area uniform perovskite thin film with narrow crystal grain size distribution, low defect density and a flat film surface is obtained, so that the efficiency and consistency of a device are improved.

The invention relates to the technical field of photovoltaic solar cells, and discloses a perovskite thin film, a preparation method and application, the perovskite thin film is prepared from a perovskite precursor solution by adopting a one-step spin-coating method or a two-step deposition method, and the perovskite precursor solution comprises 2, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5-trimethyl-1, 3, 5- The perovskite material is prepared from 2, 4-oxazolidinedione, a raw material for synthesizing the perovskite material with the ABX3 crystal structure, and a solvent. According to the invention, 2, 4-oxazolidinedione (OD) molecules are simply introduced into a perovskite precursor solution, especially into an inorganic precursor solution (such as a lead iodide precursor solution), and the porous PbI2 can be obtained by utilizing the interaction between electron-donating groups in the OD molecules and lead iodide, so that when the organic ammonium salt is spin-coated in the second step, the porous PbI2 can be obtained. The organic ammonium salt solution can rapidly diffuse and fully react, so that the perovskite thin film with larger and more uniform crystal grains is obtained, and the residual amount of harmful PbI2 is remarkably reduced.

The invention discloses a preparation method of a high-quality self-supporting polycrystalline diamond substrate. The preparation method comprises the following steps: obtaining a larger first substrate and a smaller second substrate; the molybdenum substrate is a polished molybdenum metal substrate; sowing diamond seed crystals on the first substrate by using an ultrasonic sowing method, and growing a nanocrystalline diamond epitaxial layer by using a CVD (Chemical Vapor Deposition) process; cutting the first substrate by using precise laser to obtain an annular polycrystalline diamond solid seed crystal of which the inner diameter is greater than that of the second substrate; placing a second substrate in the inner diameter of the second substrate, guiding generated tiny diamond grains to the second substrate through a boundary induction mechanism and applying direct current bias voltage, and uniformly wrapping the tiny diamond grains to form a self-supporting polycrystalline diamond substrate; according to the preparation method of the self-supporting polycrystalline diamond substrate, the orientation consistency and the crystallization quality of a diamond film are remarkably improved, and the prepared self-supporting polycrystalline diamond substrate has the advantages of being low in surface roughness, compact in structure, simplified in follow-up process and the like.