534 results about "Low melting point" patented technology

The invention relates to the technical field of part manufacturing, in particular to a hollow non-straight section composite part which is characterized in that a low-melting-point alloy is used for manufacturing a core mold to serve as a forming inner mold, fiber prepreg is laid on the surface of the core mold and subjected to curing treatment to form a shell structure, finally, the inner mold is removed in a melting mode, and the hollow non-straight section composite part is obtained. According to the hollow non-straight composite material part manufacturing method, the characteristic that materials can be controllably removed is utilized, the mold design is greatly simplified, the manufacturing cost is reduced, and meanwhile the forming freedom degree of a complex geometric structure is improved.

The invention provides a fault indication device of a lightning arrester and the lightning arrester. The fault indication device comprises a target resistor, a low-melting-point alloy, a counterweight and a shell, the target resistor, the low-melting-point alloy and the counter weight are all located in the shell; the first end of the target resistor is connected with a shell of the lightning arrester, the second end of the target resistor is grounded, the upper end of the low-melting-point alloy is in fixed contact with the target resistor, and the lower end of the low-melting-point alloy is connected with the balance weight; the shell comprises a visual subarea at the bottom; the target resistor generates different heat according to the magnitude of the leakage current of the lightning arrester, and when the temperature of the target resistor is higher than the melting point temperature of the low-melting-point alloy, the low-melting-point alloy is melted, and the counterweight falls into the visual partition. According to the device, by triggering melting of the low-melting-point alloy, advanced visual early warning can be provided before the lightning arrester breaks down, and the problem that fault indication of the lightning arrester is not timely is solved.

The invention provides a thermal response self-ceramization fireproof coating and a preparation method thereof. The thermal response self-ceramization fireproof coating is prepared from the following raw materials in parts by mass: 3 to 10 parts of acrylic monomer, 3 to 10 parts of organic sulfonate, 1 to 4 parts of silane coupling agent, 0.5 to 3 parts of silicate ester, 4 to 6 parts of ceramic precursor, 3 to 6 parts of fluxing agent and 0.05 to 0.4 part of initiator. The fluxing agent comprises a component A and a component B, the component A is one of boric oxide, zinc borate or low-melting-point glass powder, and the component B is one of phosphorus pentoxide and ammonium polyphosphate. The silane coupling agent can be copolymerized with an acrylic monomer to construct a C-C main chain, the C-C main chain and silicate ester are subjected to hydrolytic condensation to form a Si-O-Si three-dimensional network, a chemical cross-linked skeleton is formed, and the chemical cross-linked skeleton can generate silicon dioxide at high temperature to participate in a ceramization reaction; the ceramic precursor and silicate ester can form a strong physical cross-linking effect, so that the fireproof coating with a chemical and physical double-cross-linked network can be formed, and the fireproof coating has excellent mechanical property and machinability at normal temperature.

The invention belongs to the technical field of brazing materials, and particularly relates to micro-nano particle reinforced nickel-based ultralow-melting-point wear-resistant brazing filler metal and a preparation method and application thereof. The invention provides micro-nano particle reinforced nickel-based ultralow-melting-point wear-resistant brazing filler metal. The micro-nano particle reinforced nickel-based ultralow-melting-point wear-resistant brazing filler metal comprises 94-99 parts of ultralow-melting-point nickel-based brazing filler metal and 1-6 parts of micro-nano particles. The ultralow-melting-point nickel-based brazing filler metal contains B, Si, In, Sn and Cu elements at the same time, and the melting temperature of the brazing filler metal can be cooperatively reduced; and meanwhile, the micro-nano particles are added, so that the strengthening and abrasion increasing effects on the nickel-based brazing filler metal can be effectively guaranteed, and meanwhile the flowability of the brazing filler metal is not affected. Therefore, through component design of the nickel-based brazing filler metal and synergistic cooperation of the micro-nano particles, the melting point of the brazing filler metal can be remarkably reduced, the brazing filler metal can be endowed with excellent hardness and wear resistance, and the technical bottlenecks that traditional nickel-based brazing filler metal is high in melting temperature and poor in wear resistance and brazed diamond is subjected to thermal damage are solved; and the method has a wide application prospect in brazing of diamond tools.

The invention discloses a method for preparing an ultrahigh-temperature ceramic coating by an ultrahigh-temperature metal gas source based on a molten salt medium, which comprises the following steps of: mixing low-melting-point salt A, metal fluoride and metal M to obtain a mixture C, putting the mixture C into a first crucible, mixing low-melting-point salt B and metal M to obtain a mixture D, putting the mixture D into a second crucible, putting a carbon base material into a deposition furnace, and performing vacuum drying to obtain the ultrahigh-temperature ceramic coating. Heating the first crucible to melt the mixture C to obtain a melt E, and heating the second crucible to melt the mixture D to obtain a melt F; carrier gas is guided into the first crucible, the carrier gas flow passes through the melt E to form gas flow containing a metal gas source, the gas flow containing the metal gas source is guided into the second crucible, and the gas flow containing the metal gas source is filtered by the melt F in the second crucible to form a pure metal reaction gas source, and finally, a pure metal reaction gas source is introduced into the deposition furnace for deposition of the carbon base material, and the ultra-high-temperature ceramic coating is obtained. The method is easy to operate and low in cost.

The invention discloses an aluminum-based composite material and a preparation method thereof. The preparation method comprises the following steps: firstly, mixing powder of an intermediate alloy, a simple substance metal and a reinforcement with a binder, and carrying out cold pressing to form a green body; degreasing and sintering the green body to obtain a sintered part; and heating the sintered part, performing closed die forging, performing heat treatment and fine trimming to obtain a finished product, and if the performance does not meet the requirements, performing hot extrusion on the sintered part, and performing heat treatment and fine trimming to obtain the finished product. Oxide is removed through ball milling, the surface of the Al-Mg powder is activated, and passivation is protected through a binder; a reinforced phase SiC is designed to be blended with a binder, and then the mixture is mixed with other powder to form a specific microstructure; low-melting-point Sn is introduced to limit the sintering temperature, element diffusion is promoted through a liquid phase, and generation of a harmful intermediate phase is avoided; a sintered part with the density being 80-95% is adopted, a low-strain soft area is formed around a reinforced phase in cooperation with a specific microstructure, deformation coordination is improved, meanwhile, the peak aging time of the aluminum alloy is prolonged through SiC, the electric conduction and heat conduction performance is improved, and the comprehensive performance of the composite material is comprehensively improved.

The invention belongs to the technical field of thermal power heating surface treatment, and provides a gradient functional composite coating applied to a boiler heating surface and a preparation method of the gradient functional composite coating in order to solve the technical problems that an existing protective coating of the boiler heating surface is prone to abrasion and oxidation and high in cost. Collaborative design is formed, and gradient matching of mechanical properties and environmental failure resistance is achieved. The low-melting-point glass powder is combined with the rare earth catalytic effect, low-temperature ceramization is achieved, and thermal damage to a matrix is avoided. After the metal ceramic transition layer is sprayed, high-frequency induction remelting treatment is carried out, meanwhile, laser cladding is carried out on the surface of the ceramic surface layer, a nanocrystalline-amorphous composite structure is formed, and the bonding strength of the coating is improved.

The invention discloses a method for improving performance of rare earth permanent magnet sintered neodymium iron boron grain boundary diffusion, and belongs to the technical field of rare earth permanent magnet materials. The method comprises the steps that a low-melting-point metal layer and a diffusion layer containing heavy rare earth elements are sequentially formed on the surface of a clean sintered neodymium-iron-boron magnet, and then vacuum diffusion heat treatment and tempering treatment are conducted. Wherein the low-melting-point metal layer comprises at least one of copper, aluminum, gallium and tin or an alloy of the copper, the aluminum, the gallium and the tin; the heavy rare earth element comprises at least one of dysprosium, terbium, holmium and gadolinium. The low-melting-point metal layer is preferentially diffused and wets the grain boundary in the heat treatment process, heavy rare earth elements are promoted to be deeply and uniformly diffused towards the interior of the magnet along the grain boundary, so that a heavy rare earth-rich shell layer is formed outside main phase grains of the magnet, and the intrinsic coercive force is improved; meanwhile, the low-melting-point metal forms a strengthening phase at the grain boundary, the brittleness of the magnet after diffusion is improved, the surface corrosion phenomenon is restrained, and collaborative optimization of the comprehensive performance of the magnet is achieved.

The invention discloses a high-Al and Ti difficult-to-deform high-temperature alloy hot working method, which avoids the melting risk of low-melting-point intermetallic compounds through high-temperature diffusion on one hand, and can realize effective and uniform diffusion of chemical elements on the other hand; on the other hand, through gradual heating number cooling forging, a high-temperature small-deformation forging process is carried out in an as-cast structure interval, and a low-temperature large-deformation process is adopted after the as-cast structure is crushed, so that an ideal uniform and fine recrystallized grain structure is finally realized, and the problems of high possibility of cracking, non-uniform forging structure, coarse grains and the like in a high-temperature alloy forging process are solved; and the high-quality requirement for use of downstream aero-engine components is met.

The present invention relates to a bismuth alloy composition and a design method thereof. The alloy composition according to the present invention is an alloy composition comprising bismuth and a second element. The second element selected on the basis of an atomic radius difference between constituent atoms and mixing enthalpy is alloyed in an appropriate content according to a principle of improving liquid stability to provide an alloy composition satisfying a low melting point and a high degree of supercooling and exhibiting excellent flowability, which can be used as a liquid metal ion source.

The present application belongs to the technical field of ceramic alloy flywheel, and particularly relates to a liquid-liquid composite ceramic inlaid high-wear-resistance flywheel and a preparation method thereof, which is suitable for high-strength impact environment such as mines and metallurgy. The flywheel realizes metallurgical bonding of ceramic-metal by step-by-step pouring and temperature control solidification of basalt melt and high-density W-Ni-Fe alloy melt in a specific mold structure. The ceramic core is composed of multiple inorganic oxides and low-melting-point glass powder, and has excellent interface compatibility and structural stability. During the preparation process, the initial setting state of basalt and the alloy flow path are accurately controlled to improve the interface bonding strength and overall density. The finally obtained flywheel has high hardness, high toughness and excellent wear resistance, and significantly prolongs the service life.

The invention provides a high-thermal-conductivity and high-adhesion thermal interface material and a preparation method thereof, and belongs to the technical field of thermal interface materials. The thermal interface material is prepared by in-situ cross-linking reaction of the following components: a polymer matrix comprising a polymer containing active functional groups and a cross-linking agent; the heat-conducting filler accounts for more than 90wt% of the total weight of the thermal interface material; the low-melting-point organic medium accounts for 0.1-5wt.% of the total weight of the thermal interface material, and the melting point of the low-melting-point organic medium is lower than the crosslinking curing temperature of the polymer matrix; wherein the heat-conducting filler forms a continuous three-dimensional heat-conducting path in a cross-linked polymer network, and the low-melting-point organic medium is uniformly dispersed in the network. Under the ultrahigh filler content, high bulk phase thermal conductivity and high initial viscosity are realized at the same time, and the contradiction between high thermal conductivity and high interface contact resistance is solved. The high viscosity at room temperature is beneficial to operation and storage, and is softened due to melting of an organic medium at the working temperature of a device, so that the interface wettability is dynamically enhanced, and the contact thermal resistance is minimized.

The invention discloses a packaging material as well as a preparation method and application thereof. The packaging material comprises the following components in parts by mass: 40-85 parts of matrix resin, 5-30 parts of phase change PCM particles, 3-20 parts of self-repairing microcapsules, 1-8 parts of an interface compatilizer and 10-20 parts of a heat-conducting network reinforcing material, the melting point of the phase change PCM particles is not more than 80 DEG C; a core layer of the self-repairing microcapsule comprises dicyclopentadiene and a ruthenium catalyst, and a shell layer of the self-repairing microcapsule comprises polyurea or polyurethane; the PCBA packaging material with the intelligent response function is formed by combining the low-melting-point phase-change PCM particles with the self-repairing microcapsule system, when the PCBA temperature is too high, the low-melting-point phase-change PCM particles are molten, junction temperature suddenly rising is restrained through melting heat absorption, meanwhile, the adjacent microcapsules are triggered to be broken through volume expansion, DCPD monomers are released and subjected to in-situ polymerization under the action of a catalyst, and the PCBA packaging material with the intelligent response function is obtained. Microcracks generated by thermal stress are rapidly repaired, and the heat dissipation stability and the electrical insulation reliability of the material in long-term thermal circulation are remarkably improved.

The invention relates to the technical field of chemical fibers, in particular to a low-melting-point polyester FDY (fully drawn yarn) preparation process which comprises the following steps: preparing raw materials, selecting polyester chips and a low-molecular-weight polyester copolymer, mixing the polyester chips and the low-molecular-weight polyester copolymer according to a ratio, melting and blending the polyester chips and the low-molecular-weight polyester copolymer with the additive amount of 5-8wt% and the intrinsic viscosity of 0.65-0.70 dL / g, and performing extrusion molding to obtain the low-melting-point polyester FDY. And putting the mixed raw materials into a screw extruder, and carrying out melt blending and spinning treatment at 250-260 DEG C. According to the low-melting-point polyester FDY and the preparation method thereof disclosed by the invention, a component regulation end is arranged, so that a synergistic effect mechanism of a polyester matrix and a low-melting-point copolymer is accurately matched in a preparation process of the low-melting-point polyester FDY, and the uniformity of melt components is ensured; meanwhile, the copolymerization structure design directivity acts on molecular chain regularity regulation and control, thermal stability fluctuation in the spinning process is inhibited in real time, it is guaranteed that the continuous forming capacity of fibers is maintained under the high-speed spinning condition, and the stability of a production line is improved.

The invention belongs to the technical field of preparation of soft magnetic composite materials, and particularly relates to an insulation coating method and application of a soft magnetic powder material. The insulating coating method comprises the following steps: (1) uniformly mixing low-melting-point metal or alloy powder with silica sol, a silane coupling agent and a thermocuring resin glue solution to obtain coating slurry; and (2) uniformly mixing soft magnetic powder with the coating slurry obtained in the step (1), firstly performing hot-pressing curing molding at the temperature of 60-100 DEG C under a vacuum condition, and then performing hot-pressing sintering treatment at the temperature higher than the melting point temperature of low-melting-point metal or alloy powder and under an oxygen-containing atmosphere condition to obtain the insulated and coated soft magnetic powder material. According to the insulating coating method, the advantages of an organic material insulating coating method and an inorganic material insulating coating method are combined, the defects of the organic material insulating coating method and the inorganic material insulating coating method are overcome, and the stability and the insulating coating effect of the insulating coating layer are remarkably improved.

The application discloses a flexible strain sensor with high linearity and low hysteresis, a preparation method and application thereof, and belongs to the technical field of sensors. The composite sensitive material prepared by using an electric spray gun has high linearity and low hysteresis performance. The physical contact between silver nanowires and two-dimensional MXene nanosheets makes the sensor have high sensitivity in a tensile state. Meanwhile, the liquid metal particles as a structural framework have inherent room-temperature low-melting-point characteristics, so that the liquid metal particles are in a liquid state at room temperature, and the gap between the MXene nanosheets and the silver nanowires is reduced. The coordination bond formed between the MXene nanosheets and the liquid metal enhances the interface interaction between the MXene nanosheets and the liquid metal, and reduces energy dissipation. The uniform composite sensing network layer obtained based on a spray mixing technology has a uniform distance between the sensitive materials in the composite sensitive layer with the gradual increase of external stress; and the existence of the buckling structure strengthens the interaction between the sensitive materials. Therefore, the resistance has a linear relationship with the change of the stretching amount, that is, high linearity; and the flexible strain sensor has high sensitivity.

The invention discloses a silver-gold-palladium-chromium-indium-yttrium alloy and a preparation method and application thereof, and belongs to the technical field of precise materials for semiconductor detection. The alloy comprises the following components in percentage by mass: 15%-20% of Au, 15%-18% of Pd, 8%-12% of Cr, 0.1%-0.3% of In, 0.2%-0.4% of Y and the balance of Ag. According to the preparation method, alloy component design is optimized, and an optimized preparation method is combined, so that a nano-to-micron Pd-Cr dispersed phase and Y element grain boundary segregation composite strengthened structure is formed through a multi-element synergistic strengthening mechanism, and the problems of In low-melting-point volatilization, columnar crystal length-diameter ratio control, high processing wire breakage rate and the like are solved; the alloy material with excellent comprehensive performance such as hardness, resistivity and machinability is obtained, meanwhile, the preparation cost of the alloy material is reduced, and the alloy material has better adaptability to a test probe subsequently matched with a process chip below 5nm.

The invention discloses a high-strength and high-plasticity low-melting-point aluminum alloy brazing material and a preparation method and application thereof, and relates to the technical field of solder manufacturing. The low-melting-point aluminum alloy welding flux is prepared from the following components in percentage by weight: 10 to 14 percent of Si, 4 to 20 percent of Cu, 0.04 to 0.25 percent of Eu, 0.78 to 0.82 percent of Fe, 0.13 to 0.17 percent of Mn, 0.08 to 0.12 percent of Mg, 0.18 to 0.22 percent of Zn and the balance of aluminum and inevitable impurities. The Al-Si-Cu ternary alloy is constructed to form a low-melting-point eutectic phase, the melting point of the material is effectively reduced, meanwhile, Eu atoms are doped, the aluminum matrix is subjected to the pressure stress effect, the interplanar spacing is reduced, the grain size of the matrix aluminum phase is reduced, the elemental Si phase is refined, the eutectic Al-Si phase content is increased, and precipitation of the brittle Al2Cu phase is restrained; therefore, the aluminum alloy solder has high tensile strength and elongation after fracture under the condition that the melting point is low.

A braze tape includes a first portion, a second portion, and a central portion located between and adjacent to the first portion and the second portion. The first portion includes a low melting temperature alloy material, the second portion includes a high melting temperature alloy material, and the central portion includes a mixture of the low melting temperature alloy material and the high melting temperature alloy material. The central portion may gradually change between the low melting temperature alloy material and the high melting temperature alloy material. A related method is also disclosed.

The invention relates to the technical field of carbon dioxide geological utilization and storage, in particular to a sealing evaluation device and method for a low-melting-point alloy shaft plugging material, and the device comprises an observation cylinder, an outer cylinder, a simulation shaft, a gas channeling simulation mechanism, a formation pressure adjusting mechanism, a cooling mechanism, a shaft pressure adjusting mechanism and an image acquisition unit. The device is reasonable and compact in structure, alloy materials in the simulation wellbore are in an alloy melting stage, the sealing ejector pin prevents liquid alloy from flowing into the first gas injection hole, and after the alloy materials in the simulation wellbore are solidified, the sealing ejector pin is moved downwards, so that the upper end of the sealing ejector pin is located below the first gas injection hole, and the gas channeling simulation mechanism is communicated with the lower portion of the simulation wellbore; when the formation pressure adjusting mechanism works, the formation pressure adjusting mechanism is connected with the confining pressure cavity through the pressurizing hole, the simulation effect on the formation pressure around the simulation shaft can be achieved, the heating melting-cooling forming process of the low-melting-point alloy material is achieved, and the sealing capacity of the alloy plug-sleeve combination body under the actual underground working condition is evaluated.

The invention relates to a high-frequency electric resistance welding method for a transformer, and relates to the technical field of metal welding. A layer of self-reaction soldering paste is applied to the to-be-welded surface of the coil or the iron core to serve as a middle layer; and performing high-frequency resistance welding after mounting and positioning. The self-reaction soldering paste is the technical core of the invention and is composed of a powder mixture containing a solid chemical reducing agent and nano metal particles and an organic carrier. Under excitation of welding heat, the solid chemical reducing agent is subjected to an in-situ chemical reaction, and metal oxides on a welding interface are effectively removed; and meanwhile, the low-melting-point nano metal particles are rapidly melted, the purified clean interface is filled, and a compact metallurgical bonding layer is formed. Through the synergistic effect of chemical purification and physical filling, a defect-free welding joint is obtained, the welding joint has excellent mechanical strength and extremely low contact resistance, the process window is remarkably widened, and the reliability of the welding process is improved.

The invention discloses a low-melting-point high-strength hypoeutectic magnesium alloy and a preparation method thereof. The magnesium alloy comprises the following components in percentage by mass: 12.0-14.0% of Zn; 0 to 0.8 percent of Ca; 0.3 to 0.8 percent of Zr; the balance is Mg and inevitable impurities; the content of Ca is not 0, and the melting point of the magnesium alloy is not higher than 340 DEG C. By accurately controlling the addition amount of Ca and the ratio of Ca to Zn and assisting with the grain refinement effect of Zr, formation of a fine and dispersively-distributed second phase is successfully promoted in the alloy, the elongation of the obtained magnesium alloy is kept above 8%, and the elongation of the magnesium alloy is greatly improved while the basic requirement of engineering application for plasticity is met. The yield strength and the tensile strength of the Mg-Zn alloy are greatly and synchronously improved at the room temperature and the high temperature, the inherent defect that the absolute strength of a traditional low-melting-point Mg-Zn alloy is insufficient is effectively overcome, finally, ideal combination of low melting point, high strength and good plasticity is achieved, and the urgent requirement for high-performance sacrificial structural parts in the fields of aerospace and the like is met.

The application discloses a multi-component carbon fiber reinforced composite material and a low-temperature infiltration preparation method. The reaction infiltration technology is adopted, a low-melting-point infiltrant is used as a carrier, a high-melting-point component is introduced into the C / C composite material at low temperature, different components are enriched in different regions according to the reaction rate difference of each component and pyrolytic carbon, the internal content of the low-melting-point phase is reduced, and the ablation resistance is improved.

The invention belongs to the field of nuclear fuel, and particularly discloses a metal material for fuel rod gap filling and a preparation method of the metal material. The metal material comprises the following components in parts by mass: 0.01 to 44.5 parts of lead, 0.01 to 56.5 parts of bismuth, 0.01 to 61.9 parts of tin, 0.01 to 5 parts of magnesium and 0.01 to 5 parts of zirconium; and the melting point of the metal material is less than 300 DEG C. The metal material disclosed by the invention has a lower melting point and a higher heat conductivity coefficient, is applied to the in-pile service process of the fuel rod of the advanced reactor, is molten at a loop temperature to be in a liquid state, fills a gap, immerses and seals a fuel core block section, and serves as an excellent heat-conducting medium, so that heat transfer between the fuel rod core block and a cladding is realized, and the heat transfer efficiency is improved. The core block and the cladding are combined to reduce the temperature of the nuclear fuel, meanwhile, the gasification phenomenon does not exist, the phenomenon of irradiation swelling-fission gas release does not occur, the contact force between the core block and the cladding is reduced, and the service life of the fuel rod is prolonged.

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

The present application relates to the preparation method of thick polycrystalline diamond compact for oil and gas drilling, which comprises the following steps: mixing two or more kinds of diamond powder with impurities removed; sand blasting the cemented carbide substrate; sequentially loading the impurity storage layer, the diamond powder mixture layer, the low-melting-point metal sheet, the cobalt sheet and the cemented carbide substrate into a high-temperature-resistant metal cup; placing the high-temperature-resistant metal cup into a synthetic block and then into a six-surface press; performing two-stage high-temperature and high-pressure sintering, wherein the first stage is sintering at a pressure of 5.5-5.8 GPa and a temperature of 800-1300 DEG C for 60-150 seconds, and the second stage is sintering at a pressure of 6-8 GPa and a temperature of 1490-1580 DEG C for 450-700 seconds; and taking out at room temperature and normal pressure. The impurity storage layer, the low-melting-point metal sheet and the cobalt sheet are arranged, and the high-temperature and high-pressure scanning sintering method is adopted, so that the thickness of the diamond layer reaches 3-4 mm after sintering, and the service life is greatly prolonged.

The invention relates to an MXene / low-melting-point alloy electromagnetic shielding layered composite material as well as a preparation method and application thereof. Comprising the following components in percentage by mass: 40-90% of low-melting-point alloy powder, 5-40% of an MXene filler and 5-20% of a chelating agent. The layered composite material can effectively form an electron transmission channel and improve conductivity and electromagnetic shielding performance. Under the action of the low-melting-point alloy, the layered composite material can show more excellent electromagnetic shielding performance and compressive strength, the highest electromagnetic shielding effectiveness of the layered composite material is larger than 64 dB, and the highest compressive strength of the layered composite material is larger than 65 MPa. The electromagnetic shielding material has the advantages of simplicity and convenience in preparation, excellent performance, low cost, easiness in commercial application and the like, and can be widely applied to the fields of electronic equipment, communication industry, medical equipment, automobile industry, aerospace and the like as an excellent electromagnetic shielding material.

The application belongs to the technical field of soft magnetic composite material preparation, and particularly relates to an insulation coating method for soft magnetic powder material and application. The insulation coating method comprises the following steps: (1) uniformly mixing low-melting-point metal or alloy powder, silica sol, silane coupling agent and hot curing resin glue solution to obtain coating slurry; (2) uniformly mixing soft magnetic powder and the coating slurry of step (1), and then performing hot-pressing curing forming at a temperature of 60-100 DEG C and under vacuum condition, and then performing hot-pressing sintering treatment under a temperature higher than the melting point of the low-melting-point metal or alloy powder and under an oxygen-containing atmosphere condition to obtain the insulation-coated soft magnetic powder material. The insulation coating method of the application combines the advantages of the organic material insulation coating method and the inorganic material insulation coating method, overcomes the respective defects, and significantly improves the stability and insulation coating effect of the insulation coating layer.

The invention belongs to the technical field of titanium alloy processing, and particularly relates to a preparation method of a titanium-copper alloy plate. According to the method, high-quality sponge titanium and high-purity electrolytic copper serve as raw materials, a Ti-5Cu alloy plate ingot is formed at a time through an EB electron beam cold bed melting process, volatilization and burning loss of a low-melting-point alloy element Cu are reduced by introducing pure argon or helium protective atmosphere with a certain pressure into a furnace chamber, gas impurities and low-melting-point impurities in the alloy are removed according to the partial pressure principle, and the high-quality sponge titanium and the high-purity electrolytic copper are obtained. The electrode preparation process is omitted, and the production process is simplified. By utilizing the advantages that the Ti-5Cu alloy is small in deformation resistance and good in plasticity when being rolled in a beta-phase region, the Ti-5Cu alloy is rolled in the beta-phase region above the phase transition temperature, it is guaranteed that the deformation amount of the alloy in the beta-phase region reaches 40-90%, and it is avoided that when machining of the beta-phase region is finished, thick grains are reserved in metal, and the mechanical property of the plate is reduced; and a uniform fine grain structure or a basket structure and relatively high mechanical properties can be obtained.

The application discloses a method for brazing ferrite and copper based on a nano-silver and glass phase composite filler, which is used for realizing the welding of ferrite and copper, and the method comprises the following steps: S1, preparing a paste based on nano Ag powder and a low-melting-point glass phase; S2, pretreating the ferrite and copper to be brazed, coating the paste on the surfaces to be welded of the ferrite and copper to be brazed, and assembling to form a ferrite-copper assembly; and S3, heating and brazing the assembled ferrite-copper assembly. The application has the advantages of high connection strength and good heat conductivity.