742 results about "Copper substrate" patented technology

The invention relates to the technical field of circuit substrate manufacturing, and particularly discloses a preparation method of a composite solder sheet and an AMB ceramic copper-clad plate. The composite solder sheet is composed of an active metal foil and a copper-containing layer modified on the surface of the active metal foil, and the preparation method of the copper-clad plate comprises the following steps: after the surface of the active metal foil is pretreated, the copper-containing layer is deposited to prepare the composite solder sheet, and the composite solder sheet is placed between a copper substrate and a ceramic sheet to be pressed and assembled. And performing vacuum brazing on the assembly to complete the preparation of the ceramic copper-clad plate. A composite solder sheet containing active metal is adopted, high-temperature element diffusion during vacuum brazing is utilized at the diffusion temperature to achieve alloying of a composite solder layer, and then heat preservation is conducted at the brazing temperature to achieve uniform melting of solder and wetting metallurgical reaction between the solder and copper and between the solder and a ceramic substrate. By means of the preparation method, low-cost and high-reliability preparation of the AMB ceramic copper-clad plate can be achieved, and the prepared AMB ceramic copper-clad plate also has high peel strength and lower weld porosity.

The invention relates to a formation method of a lithium-free negative electrode battery, and belongs to the technical field of lithium batteries. The testing method comprises the following steps: standing at low temperature before first-circle charging to enable the interior of the battery to reach a steady state, carrying out short-time and low-electric-quantity charging by adopting large current, and charging and discharging for several circles by adopting small current after the interior of the battery reaches the steady state at room temperature. According to the formation process provided by the invention, a compact seed crystal layer formed by lithium cores can be formed on the surface of Cu in situ at low temperature and high current density, so that the physical binding force between a deposited lithium layer and a copper substrate is remarkably enhanced, and the contact resistance is reduced, thereby inhibiting the growth of moss or dendritic metal lithium and realizing low-porosity and high-compactness lithium deposition; and a more uniform and stable SEI film is formed through low-current deposition, so that the coulombic efficiency and the cycling stability of the battery are improved.

The invention discloses a self-supporting Co / CoO / Co3O4 catalytic electrode rich in oxygen vacancy as well as preparation and application of the self-supporting Co / CoO / Co3O4 catalytic electrode. The preparation method of the catalytic electrode comprises the following steps: step 1, dissolving Co (NO3) 3.6 H2O and dimethylimidazole in ethanol, uniformly mixing, adding a foamy copper substrate, putting into a drying oven, carrying out solvothermal reaction to generate a Co-ZIF precursor, and drying after the reaction is finished to obtain foamy copper containing the Co-ZIF precursor; and 2, putting the foamy copper containing the Co-ZIF precursor into a tubular furnace, introducing hydrogen-argon mixed gas, and carrying out reduction calcination at 300-500 DEG C to obtain the catalytic electrode. The invention provides application of the catalytic electrode as a cathode in a reaction of synthesizing ammonia through nitrate electroreduction. The process conditions are simple, the prepared catalytic electrode can effectively promote the electroreduction process of nitrate radicals, and high ammonia yield and high Faraday efficiency are achieved.

The invention belongs to the field of module parasitic parameter reduction, and discloses a multi-loop decoupling-based low electromagnetic parasitic parameter SiC power semiconductor module, which is characterized in that an independent copper substrate is adopted as an alternating current copper layer to be laminated on a DBC (Direct Bond Copper) ceramic substrate, and a lower tube chip is flipped and then welded on the lower DBC substrate which is disconnected from a radiator; an upper tube chip and a lower tube chip are connected with a copper substrate above through a copper-molybdenum-copper cushion block, and an alternating current output end of the module is suspended above the DBC substrate through the chips and the cushion block. According to the invention, parasitic capacitance of the module AC output end to the grounding radiator can be almost completely eliminated, power-heat transfer loop capacitive decoupling is realized, common-mode current of a SiC device under high-speed switching is significantly reduced, and electromagnetic interference of a high-frequency switching circuit to a driving circuit and a control system is effectively reduced. And meanwhile, the parasitic inductance of the module is remarkably reduced, and orthogonal decoupling of a signal-power loop magnetic flux space is realized.

The present invention belongs to the technical field of photovoltaic modules, and specifically relates to a reflective busbar and a manufacturing method thereof. The reflective busbar includes a solder layer, a copper substrate, an aluminum reflective layer and a high-light-transmittance protective film. The bottom and both sides of the aluminum reflective layer are embedded in the interior of the copper substrate. The top surface of the aluminum reflective layer is covered with a high-light-transmittance protective film. The bottom surface of the copper substrate and the outside of the copper substrate on the side are covered with a solder layer. The high-light-transmittance protective film extends from the top surface of the aluminum reflective layer to the top surface of the copper substrate and is seamlessly connected to the solder layer. The top surface of the aluminum reflective layer of the side reflective busbar is an inclined surface, and the top surface of the aluminum reflective layer of the middle reflective busbar is a serrated structure. The reflective busbar of the present invention can improve the light reflectivity of the reflective busbar and improve the module power on the premise of significantly reducing the cost of the busbar material. At the same time, it can solve the corrosion problem caused by the contact between aluminum and materials such as EVA, and can stabilize the service life of the photovoltaic module.

The invention discloses a preparation method and application of a nickel-doped graded nano array electro-catalysis material, and relates to the technical field of nano material preparation, the preparation method comprises the following steps: preparing a solution by taking foamy copper as a substrate material and sodium hydroxide and ammonium persulfate as raw materials; a copper hydroxide nanobelt array precursor is synthesized on a foamy copper substrate in an in-situ growth mode through chemical oxidation treatment, then the precursor is converted into a nickel-doped cuprous sulfide nanorod array through hydro-thermal treatment, uniform nanosheets are formed on nanorods through the electro-deposition process, and the nickel-doped graded nanorod array electro-catalysis material can be obtained. By optimizing the synthesis method and adjusting the doping proportion, the obtained graded nano array shows relatively low overpotential and excellent stability in an electro-catalytic reaction, and the problems of low catalytic efficiency, poor durability and the like and insufficient stability of an existing catalyst are solved.

The low-temperature welding method comprises the steps that firstly, abrasive paper is adopted for polishing the surfaces of a copper substrate and an aluminum substrate, then a welding clamp is adopted for fixing the aluminum substrate, then an interconnection interface of the aluminum substrate is filled with proper Sn0. 3Ag0. 7Cu alloy powder, the aluminum substrate is placed on a constant-temperature table to be heated after being covered with the copper substrate, and the copper substrate and the aluminum substrate are welded at the same time. And simultaneously applying ultrasound and pressure to the copper substrate and the aluminum substrate, and continuously keeping the temperature and the pressure after the ultrasound is stopped until the experiment is finished. The prepared connector is free of zinc element, the copper-aluminum connector with the (Sn) + Al2Cu + AlCu ternary eutectic is formed and has good plasticity and toughness, the welding method is easy to operate, the welding temperature is low, the welding time is short, the production cost is reduced, and the production efficiency and the product reliability are greatly improved.

The invention discloses low-temperature curing silver-coated copper composite slurry and a preparation method thereof. The conductive adhesive comprises the following raw material components in percentage by weight: 60-80% of conductive phase, 2-2.8% of adhesive, 5-10% of resin and 3-8% of additive, and 20%-30% of a solvent. Wherein the conductive phase is formed by compounding spherical silver-coated copper powder and flaky silver powder, and the silver content is reduced and the sheet resistance of the silver-coated copper composite conductive paste is below 25m omega / square through a copper matrix surface silver plating process. A step-by-step mixing technology is adopted in the preparation process, resin and a solvent are dispersed at a high speed at 60 DEG C, then conductive powder is introduced to avoid agglomeration, and a uniform and compact conductive network is finally formed after grinding. After being cured at the low temperature of 130-180 DEG C, the paste has excellent adhesive force and durability, can be applied to the fields of heterojunction solar cells, flexible circuits and the like, and remarkably improves the photoelectric conversion efficiency and the processing adaptability.

The invention provides a preparation method of a copper-clad substrate and the copper-clad substrate. The preparation method comprises the following steps: providing a copper-clad substrate for forming an inner-layer core plate; the copper-clad substrate comprises a copper-clad plate base material and a copper foil arranged on the surface of the copper-clad plate base material; executing an interface modification process on the surface of the copper foil; forming a dry film photoetching film on the surface of the copper foil after interface modification; performing exposure and development processing on the dry film photoetching film to form a dry film photoetching film with a circuit pattern; and the dry film photoetching film is used as a mask to execute an etching process so as to form a circuit pattern on the copper-clad substrate, so that the technical effect of improving the wiring precision is realized.

The invention relates to the technical field of superconducting material processing, in particular to a preparation method of an Nb3Sn superconducting wire. The method mainly comprises the steps that Nb-Zr alloy is loaded into the exterior and / or the center of a Sn-Cu single-core rod, oxide powder is filled between the Nb-Zr alloy and the Sn-Cu single-core rod, then the Sn-Cu single-core rod and the Nb-Zr alloy are loaded into a copper substrate, and Nb3Sn subcomponents are obtained after multi-pass stretching, forming and fixed-length cutting; and uniformly arranging the Nb3Sn sub-components in the copper pipe along the circumferential direction to form a bundle, and after multi-pass stretching, carrying out heat treatment and cutting to obtain the Nb3Sn superconducting wire. By introducing the artificial point pinning array in density gradient distribution, the critical current density of the Nb3Sn superconducting wire in a high magnetic field of 8T-16T is enhanced, the problems that an existing uniform artificial point pinning center scheme generates a matching effect and limits the actual application of the superconducting wire are solved, and the decline degree of the critical current density of the Nb3Sn superconducting wire in the high field is relieved.

The invention relates to a method for constructing a composite super-hydrophobic coating through double bonding. The preparation method comprises the following steps: taking a clean copper sheet which is not pretreated as a substrate, dipping the copper sheet in a suspension consisting of nanoparticles and sulfydryl-containing siloxane ethanol, taking out, washing, drying, dipping in a perfluoromercaptan ethanol solution, taking out, washing, and drying to obtain the copper-based super-hydrophobic surface coating. The coating prepared by the method has excellent super-hydrophobicity, icing resistance and stability. Different from an existing conventional preparation method, the method has the advantages that pretreatment operation such as abrasive paper polishing, strong acid etching or anodic oxidation does not need to be carried out on a copper sheet, and micro-nano roughening and low-surface-energy self-assembly can be completed on the copper surface only through two-step normal-temperature dipping. The method is simple in preparation process, mild in condition, free of expensive equipment, thin in coating thickness and small in influence on electric conduction and heat conduction of the copper substrate, intrinsic performance of copper can be reserved, the electric conduction / heat conduction characteristic of the copper substrate is considered, and the method has wide application value and prospects.

The invention discloses a composite two-phase flow micro-channel radiator for high-density heat flow, and belongs to the technical field of heat dissipation, the composite two-phase flow micro-channel radiator for high-density heat flow comprises a vapor chamber for heat transfer, a manifold copper substrate is arranged on the vapor chamber, a diversion trench is formed in the bottom surface of the manifold copper substrate, a liquid inlet is formed in one side surface of the manifold copper substrate, and the liquid inlet is communicated with the diversion trench; a flow guide groove is formed in one side face of the manifold copper substrate, a liquid outlet is formed in the other side face of the manifold copper substrate and communicated with the flow guide groove, protruding strips are arranged on the temperature equalizing plate and arranged in the flow guide groove, a liquid conveying groove is formed between every two adjacent protruding strips, a first cavity is formed in the temperature equalizing plate, a second cavity is formed in each protruding strip, and the first cavity is communicated with the second cavity. The heat dissipation device has the advantages that heat rapidly increased in unit area of equipment can be timely and effectively dissipated, and the overall heat dissipation efficiency and the heat dissipation effect are improved.

The invention discloses a method for chemically plating silver on the surface of a nickel-plated ceramic copper-clad substrate, and relates to the technical field of metal surface treatment. The preparation method comprises the following steps: S1, sequentially adding nitric acid, imidazole and a surfactant into deionized water, and uniformly mixing to obtain an activating agent; s2, after the ceramic copper-clad substrate is pretreated, chemical nickel plating treatment is carried out, cleaning and drying are carried out, and a nickel-plated ceramic substrate is obtained; and S3, the nickel-plated ceramic substrate is immersed in an activating agent for activating treatment, chemical silver plating treatment and post-treatment are conducted, and a product is obtained. According to the method provided by the invention, the problem of copper ion migration in the later silver welding process of chemical silver plating on the surface of the ceramic copper-clad substrate can be solved, and the performance of the packaging module is improved.

The invention provides polyacrylate alkali-soluble resin as well as a preparation method and application thereof. The polyacrylate alkali-soluble resin has a structure as shown in a general formula (VI). According to the polyacrylate alkali-soluble resin provided by the invention, the six-membered cyclic anhydride with a rigid structure is introduced into a main chain, and the characteristics of the rigid structure and ester groups of the cyclic anhydride are utilized, so that the etching resistance and the adhesion to a copper substrate can be effectively enhanced, and the problems of short circuit and open circuit in a circuit board manufacturing process are reduced; the photosensitive dry film prepared from the photosensitive resin composition has the advantages of excellent adhesive force, high resolution ratio, high film stripping speed and no large film residue residue.

The invention discloses a low-temperature and low-pressure connection method for copper surface in-situ nanocrystallization, and relates to a copper connection method. The method aims at solving the technical problems that operation of current copper sintering connection is complex, an intermediate layer needs to be added for assistance, the connection strength is low, the interface welding rate is low, the connection temperature and pressure are too high, and the heat preservation time is long. The nanolayer is prepared on the surface of the copper substrate by adopting an in-situ nanocrystallization method, the nanostructure has relatively large surface energy, sintering connection can be realized at low temperature and low pressure, a high-strength joint is formed, and the method can be applied to the fields of copper connection, electronic packaging and the like. And under the condition of 125 DEG C / 10min / 5MPa, the shear strength of the obtained joint can reach 118.9 MPa without additionally adding a nano-particle sintering middle layer, and a connection structure with low connection temperature, short time, low required pressure and high mechanical stability is realized. The method is simple and effective to operate, can realize low-temperature connection of large-size samples, and has a wide application prospect.

According to the printed circuit board and the manufacturing method for the same-layer local multiple-copper-thickness circuit pattern of the printed circuit board, the same-layer high-frequency signal circuit on the printed circuit board is patterned step by step, and the multiple-copper-thickness circuit is accurately constructed in the same circuit layer in combination with the two-time pattern electroplating process and the voltage conversion process. Specifically, a layer of surface copper foil is additionally covered on the surface of the copper foil of the copper-clad substrate to form a voltage-transferring substrate, the surface copper foil is used as a connecting layer between a first circuit layer and a second circuit layer, and two surfaces of the surface copper foil are independently electroplated twice, so that the copper thickness distribution of different circuit areas is accurately controlled, and the voltage-transferring effect is improved. And finally, a plurality of signal circuit patterns with coexisting copper thicknesses are constructed in the surface copper layer on the inner-layer voltage conversion substrate, so that the fineness and reliability of the signal circuit are ensured to meet the high-frequency signal transmission requirement, the layout flexibility of the signal circuit on the printed circuit board is improved, the impedance matching of the signal circuit is ensured, and the signal loss is reduced at the same time.

The invention belongs to the technical field of laser cladding processing, and provides a method for preparing an ablation-resistant copper alloy through a blue laser cladding process and the ablation-resistant copper alloy. The method comprises the following steps that alloy powder is subjected to ball milling, and mixed powder is obtained; the alloy powder is CuCr powder, CuW powder, ODS-Cu powder, SiO2 / Cu powder or C / Cu powder; and the mixed powder is used for preparing a cladding layer on a copper base material by adopting a blue laser cladding process. According to the method, the characteristic that a copper material is high in blue laser absorptivity is utilized, the problems of heat input accumulation, air holes, inclusions and the like under the conditions of low absorptivity and high energy density are avoided, and laser process parameters are controlled to form a molten pool on the surface of a copper base material; and the coaxial powder feeding device gathers the powder material into the molten pool for melting and rapid cooling and solidification by utilizing protective gas to form a cladding layer with excellent performance, so that the surface of the copper base material is modified, and the performance of the copper base material is improved.

The invention provides a packaging structure and a packaging method for improving the heat dissipation performance of an IGBT power module. The packaging structure comprises a copper substrate, a first epoxy glue layer, an epoxy resin-based composite material layer, a second epoxy glue layer, an upper bridge copper layer, a lower bridge copper layer, a chip solder layer and a power chip which are sequentially arranged from bottom to top, wherein the upper bridge copper layer and the lower bridge copper layer are integrally arranged; the power chip comprises an upper bridge chip and a lower bridge chip; the chip solder layer comprises an upper bridge chip solder layer and a lower bridge chip solder layer; the upper bridge chip solder layer is arranged on the upper bridge copper layer, and the upper bridge chip is arranged on the upper bridge chip solder layer; the lower bridge chip solder layer is arranged on the lower bridge copper layer, and the lower bridge chip is arranged on the lower bridge chip solder layer. According to the packaging structure, the epoxy resin-based composite material layer is adopted as the insulating layer, copper and a welding layer are reduced in heat flow transmission, the heat resistance from the chip to the shell is reduced, and the heat dissipation performance is improved; the copper layers of the upper and lower bridge arms are integrated, leads between the upper and lower bridges are reduced, the power loss of the IGBT is reduced, and the heat is reduced.

The invention relates to a copper substrate embedding method for separated special-shaped copper blocks and a circuit board, and the method comprises the following steps: processing a plurality of special-shaped copper blocks with preset shapes on a copper plate, and reserving a plurality of connecting ribs which are not completely cut off between the adjacent special-shaped copper blocks; a gap between every two adjacent special-shaped copper blocks is filled with resin; a heat-conducting insulating layer and a copper foil are sequentially overlaid on the two opposite faces of the copper plate to form a stacked structure, and a substrate is formed through high-temperature pressing; an isolation groove is formed in the position, corresponding to the connecting rib, of the substrate, and the isolation groove cuts off the connecting rib; the isolation groove is filled with resin, and the resin overflowing out of the plate surface is rubbed down; and conducting treatment: forming a continuous conductive copper layer on the surface of the resin filling area. According to the invention, no copper groove needs to be buried, the copper block can be processed into a specific shape, and the distance between two adjacent special-shaped copper blocks is controlled to be 1.0 mm, so that the number and the area of the copper blocks buried in the substrate are greatly increased, and the heat dissipation performance and the electrical performance of the circuit board are improved.

The invention discloses a method for reducing grafting printing deformation of a plate-shaped copper alloy part, and belongs to the technical field of grafting printing. The printing method comprises the following steps: processing countersunk head screw holes in a pure copper substrate (avoiding a printing area), and locking the countersunk head screw holes to a printing bottom plate by using screws; printing parameters are as follows: the slice layer thickness is 0.03 mm, the laser power is 180-220 W, the scanning speed is 950-1050 mm / s, checkerboard scanning is performed, and interlayer cooling is performed for 10-20 s; during powder laying and printing, first-layer remelting is carried out to enhance combination; annealing treatment: keeping the temperature at 600 DEG C for 2 hours, and then cooling; and finally, the screws are taken down to obtain the low-deformation plate-shaped part. The thermal expansion coefficient difference between the copper alloy and the pure copper substrate is improved through the specific copper alloy material, the deformation risk is avoided, and the good heat-conducting property and mechanical property of the product can be guaranteed; and secondly, in combination with a printing process, residual stress is reduced.

The invention discloses a three-dimensional porous current collector as well as a preparation method and application thereof, belongs to the technical field of a sodium metal battery current collector, and solves the problem that the electrochemical performance of a metal sodium battery without a negative electrode in the prior art is not ideal enough. The three-dimensional porous current collector comprises a copper substrate and bismuth nanosheets vertically grown on the surface of the copper substrate, wherein the copper substrate is of a net structure, and the bismuth nanosheet is of a three-dimensional honeycomb structure. The three-dimensional porous current collector provided by the invention has ultra-stable sodium deposition stripping performance and excellent long cycle stability.

The invention discloses a green laser assembly, an optical module and application of the green laser assembly in photovoltaic assembly processing, a shell is provided with a first fixed reflector coated with a reflecting film for reflecting 1064nm, a first acousto-optic Q switch and a second acousto-optic Q switch are orthogonally arranged, an Nd: YAG laser uses an Nd: YAG crystal rod with the diameter of 6mm and the length of 166mm, and a second fixed reflector coated with a reflecting film for reflecting 1064nm is arranged on the Nd: YAG crystal rod. The first dichroscope transmits 1064nm and reflects 532nm to improve the conversion efficiency of frequency multiplication, the LBO crystal 16 is placed close to the second dichroscope to improve the power density and the conversion efficiency, and the second dichroscope reflects 1064nm and transmits 532nm. And the light with the wavelength of 532nm transmitted by the second dichroscope is coupled into an input end optical fiber of the optical fiber beam splitter after passing through the optical isolator and the first lens. The short-wavelength green laser is adopted, the photovoltaic welding strip is mainly composed of the copper base material and the tin alloy, the green laser absorptivity is far larger than the near-infrared wavelength (about 1 micron) absorptivity, and the laser absorptivity of the welding strip is remarkably improved.

The invention relates to Sn-Bi-In-Ag-Zn high-reliability high-entropy alloy low-temperature solder for advanced packaging and a preparation method of the Sn-Bi-In-Ag-Zn high-reliability high-entropy alloy low-temperature solder, and belongs to the technical field of electronic packaging materials. The solder comprises, by atomic percent, 25%-35% of tin, 25%-35% of bismuth, 25%-35% of indium, 5% of silver and 5%-10% of zinc, and preparation of the solder is achieved in an induction melting mode. Main phases of the Sn-In-Bi-Ag-Zn high-reliability high-entropy alloy low-temperature solder for electronic packaging are the tin-based solid solution and the indium bismuth phase, bismuth and indium atoms are subjected to high solid solution in the tin-based solid solution, and solid solution strengthening of the solder is promoted. The melting point is only 80-90 DEG C, and the warping problem caused by CET mismatching can be effectively reduced due to the extremely low melting point. The low-temperature wettability is good, and the wetting angle is smaller than or equal to 33 degrees when the copper substrate is wetted at 120 DEG C. Meanwhile, inhibition of interface IMC rapid growth can be achieved without a diffusion barrier layer, a thin IMC layer can still be kept under the conditions of long-time and multiple times of backflow, the volume ratio of the IMC in a micro welding spot can be remarkably reduced, the influence of the IMC on the mechanical property and reliability of the welding spot can be reduced, good mechanical property can still be kept after long-time and multiple times of backflow, and the service life of the welding spot can be prolonged. The method is suitable for advanced packaging such as flexible packaging and 3D IC packaging which require low packaging temperature or high thermal reliability.

The invention provides a nanoelectrode preparation method of a two-dimensional material memristor, and relates to the technical field of semiconductor device preparation, and the method comprises the steps: carrying out the spin coating of a PMMA diluent on a substrate, carrying out the electron beam exposure, carrying out the low-temperature development, and forming a patterned bottom contact electrode; performing physical vapor deposition, photoresist removal and stripping on the patterned bottom contact electrode to obtain a bottom contact electrode; preparing an insulating layer on the substrate for preparing the bottom contact electrode by using an atomic layer deposition mode; copper substrate etching is carried out on the two-dimensional material with the copper substrate, and the two-dimensional material with the copper substrate is transferred to the position above the insulating layer; performing patterning treatment on the transferred two-dimensional material to obtain a patterned two-dimensional material electrode; pMMA diluent is spin-coated on the surface of the substrate after patterning of the two-dimensional material, electron beam exposure and low-temperature development are carried out after baking and glue solidification, and a patterned top contact electrode is formed; and performing physical vapor deposition on the patterned top contact electrode to obtain the top contact electrode. The size of the device can be greatly reduced, and the performance uniformity of the device is improved.

The invention discloses a red copper strip for an IGBT copper substrate and a processing method of the red copper strip, and belongs to the technical field of red copper processing. The red copper material is smelted, cast and processed into a cast ingot; heating is conducted in a stepping heating mode, the temperature range is 840-1000 DEG C, hot rolling and face milling are conducted, and a strip with the thickness being 15-20 mm is machined; rough rolling is conducted on the strip, and the strip is machined to be 3.8-4 mm in thickness through 8-pass rolling; annealing and cleaning; the cleaned strip is subjected to two-pass finish rolling, and a strip with the thickness ranging from 2.8 mm to 3.5 mm is formed; and cleaning to obtain the red copper strip for the IGBT copper substrate. The heat treatment, rough rolling and annealing processes in the red copper machining process are improved, the obtained red copper strip for the IGBT copper substrate is good in surface consistency, and the heat conduction performance is improved when the red copper strip is applied to an IGBT module.

The invention discloses a grafting 3D printing method for improving the binding force of a copper substrate and a copper grafting piece and application of the grafting 3D printing method, and belongs to the technical field of grafting printing. The grafting 3D printing method for improving the binding force of the copper substrate and the copper grafting piece is characterized in that the copper substrate is subjected to roughening treatment before printing, and abrasive materials are sprayed at the angle of 30-60 degrees through automatic sand blasting equipment, so that uniform tiny pits (concave-convex structures) with certain depth are formed in the surface of the copper substrate; during control printing, D0 layer entity scanning is conducted twice, and contour scanning is conducted three times; the D1 layer entity is scanned once, and the contour is scanned twice; the contour and entity of the D2 layer and the subsequent printing layer are scanned once respectively, so that the binding force of a grafting printing interface is greatly improved, in a vertical drawing test, it is guaranteed that the fracture position is not located on the grafting interface, and the stability of a printed product and the durability of the printed product in coping with various application scenes are guaranteed.

The invention discloses a high-hardness high-thermal-conductivity gradient structure copper material which is composed of a base body and a surface layer combined on the surface of the base body, the base body is oxygen-free copper, and the surface layer is a copper boron nitride alloy composed of two phases of copper grains and a boron nitride film. The surface layer and the base body are metallurgically bonded; the boron nitride thin film in the copper boron nitride alloy is clamped between copper crystal grains to form a gradient distribution structure which is in a net shape to separate and wrap the copper crystal grains, and the boron nitride content of the gradient distribution structure is continuously reduced from the outside to the inside. The invention further discloses a preparation method of the copper material, oxygen-free copper serves as a substrate to form a base body in the copper material, copper-boron alloy with boron components distributed in a gradient mode is prepared on the surface of the oxygen-free copper substrate through laser additive manufacturing, then the copper-boron alloy on the surface of the oxygen-free copper is nitrided into copper-boron nitride alloy through nitriding treatment, and then the surface layer of the copper material is formed. And the composite copper material with high hardness and high thermal conductivity is obtained. The prepared copper material can meet the service requirements of the heat management industry on the wear resistance and the heat dissipation performance of components at the same time.

The invention belongs to the technical field of electro-catalysis carbon dioxide reduction, and particularly relates to a three-dimensional porous copper oxide-zinc bimetallic film electrode for electro-reduction of carbon dioxide and preparation and application of the three-dimensional porous copper oxide-zinc bimetallic film electrode. The preparation method comprises the following steps: firstly, carrying out surface pretreatment on a copper substrate, then carrying out pulse current electrodeposition and dynamic etching on the surface of an electrode in a mixed electrolyte containing zinc salt, copper salt and sodium salt, and finally, carrying out constant current structure reconstruction on the electrode by adopting a long-time reduction method to prepare the three-dimensional porous copper oxide-zinc bimetallic film electrode. The electrode has a unique nano pore channel structure, rapid transfer of interface charges is promoted, and the electrode has rich active sites due to the synergistic effect of a heterostructure. The preparation method has the dynamic regulation and control advantage of pulse deposition and the structural stability of constant-current deposition, a template agent does not need to be added in the preparation process, and the process controllability is high. The obtained electrode shows excellent CO product selectivity, activity and stability in an electro-catalysis carbon dioxide reduction reaction.

The invention is suitable for the technical field of heat pipe experiment systems, and provides a heat pipe experiment system and method based on visual visualization and dual-seal temperature control, and the system comprises a visual heat pipe, a temperature adjustment module, a data collection module, a liquid injection module and a glass temperature monitoring feedback module. The visual heat pipe adopts an aluminum alloy cover plate, visual glass and a copper substrate to form a double-sealing structure. The system integrates a glass temperature monitoring and feedback mechanism, prevents the observation window from fogging, prevents the temperature of the observation window from being too high, and guarantees high-definition visual observation. And the data acquisition module synchronously records the thermal parameters and the dynamic image of the condensed liquid drop, and quantitatively analyzes the behavior of the liquid drop through an image processing technology. The system can realize high-definition observation, high-precision temperature control and quantitative analysis of the internal condensation process of the flat heat pipe at different inclination angles and under different working conditions, and is suitable for in-depth research of a phase-change heat exchange mechanism and heat pipe performance.

The invention relates to the technical field of composite metal materials, in particular to a silver-coated graphene copper composite material and a preparation method thereof, and aims at solving the problems that traditional silver-coated copper powder is high in silver consumption, copper is oxidized due to the fact that a silver layer is prone to being damaged, and conductivity is insufficient. The method comprises the steps that a graphene coating layer is formed on a copper powder substrate in situ through chemical vapor deposition, and graphene copper powder is obtained; performing etching treatment on the graphene copper powder to controllably expose part of the copper substrate so as to form anchoring points for silver ion deposition; carrying out reduction treatment on the etched graphene copper powder so as to ensure that an anchoring site has chemical activity; in a reductive liquid phase environment, enabling a chemical silver plating solution to react with the graphene copper powder subjected to reduction treatment, and guiding silver ion deposition by utilizing an anchoring point, so as to form a silver coating layer on the surface of the graphene coating layer; and separating and drying the reacted system to obtain the silver-coated graphene copper composite material. The material is better in oxidation resistance and conductivity, and the process is free of waste liquid.