167results about How to "Lower interface thermal resistance" patented technology

The invention relates to the technical field of composite materials, in particular to high-thermal-conductivity organic silicon resin and a preparation process thereof. The invention relates to a preparation process of organic silicon resin with high thermal conductivity. The preparation process comprises the following steps: adding a nano filler with high thermal conductivity into a silane coupling agent for surface modification; adding the modified filler into an organic silicon resin matrix, mixing, adding a cross-linking agent, and carrying out shearing treatment; pouring the mixed solution into a mold, and treating in a strong electromagnetic field; placing the mold in a vacuum filling device to remove bubbles; and putting the mixture into a drying oven for crosslinking and curing to obtain the high-thermal-conductivity organic silicon resin. Through the high-speed shearing effect, the filler is arranged in the matrix in the shearing direction to form a continuous heat conduction path, the filler is regularly guided through a strong electromagnetic field to form a continuous heat conduction channel, bubbles in the material are removed under the vacuum condition, it is ensured that organic silicon resin is filled into pores of a filler framework, and the heat conduction performance of the filler is improved. The uniformity and integrity of the material are improved, and the interface thermal resistance is reduced, so that the heat-conducting property is improved.

The invention discloses a method for applying liquid metal as a thermal interface material, and relates to the technical field of thermal management. The liquid metal with high thermal conductivity is selected as a core heat-conducting medium, the liquid metal shows excellent heat-conducting performance at the normal temperature, the gallium-indium-tin alloy with high thermal conductivity is selected as the core heat-conducting medium, the heat-conducting performance of the thermal interface material is remarkably improved, and the heat-conducting performance of the thermal interface material is greatly improved at the normal temperature. The liquid metal shows excellent heat conduction performance and can form an almost unobstructed heat conduction path, so that heat generated by the electronic equipment is quickly transferred to the radiator, in addition, in combination with the intelligent response material layer, the shape memory polymer is subjected to phase change at a specific temperature, the liquid metal is driven to form a closer contact interface, and the heat dissipation efficiency is improved. The interface thermal resistance is further reduced, and the heat conduction efficiency is remarkably improved.

The invention relates to the technical field of powder metallurgy, in particular to a tungsten-copper alloy preparation method and a tungsten-copper alloy. The preparation method of the tungsten-copper alloy comprises the following steps: mixing double-scale compound tungsten powder containing nanocrystals and ultra-fine grains or double-scale compound tungsten-tungsten oxide powder containing nanocrystals and ultra-fine grains with copper oxide powder to obtain precursor slurry; drying the precursor slurry to obtain precursor composite powder; the precursor composite powder is subjected to segmented reduction, tungsten-copper composite powder is obtained, and tungsten crystal grains in the tungsten-copper composite powder are distributed in a double-scale mode of nanocrystals and ultra-fine crystals; and the tungsten-copper composite powder is prepared into a blank and sintered, and the tungsten-copper alloy is obtained. The heat conductivity and density of the tungsten-copper alloy can be improved.

The invention discloses a carbon fiber composite material as well as a preparation method and application thereof. Based on the structural design of the liquid crystal polymer with different dimensions, a liquid crystal polymer molecule assembly layer is constructed on the surface of the carbon fiber, the roughness and surface activity of the surface of the carbon fiber are improved, and meanwhile, the interface performance of the composite material is improved through the efficient redirectionality of the liquid crystal polymer under the microcosmic mesocrystal domain structure and the load. Besides, based on the high orientation of the liquid crystal polymer in the interface phase of the composite material, a multi-dimensional heat conduction network is constructed, the dominant vibration mode of the carbon fiber and the resin matrix in the phonon heat transfer process is effectively coupled, the possibility of carrier phonon scattering at the interface is reduced, the interface thermal resistance is greatly reduced, and the thermal conductivity of the composite material is improved. Therefore, the heat-conducting property of the composite material is improved.

The invention belongs to the field of thermal management materials, and particularly relates to insulating high-thermal-conductivity gel and a preparation method thereof. The preparation method comprises the following steps: firstly, preparing modified copper powder, modified boron nitride and nano metal liquid drops respectively, forming a solid-liquid mixed filler by using a solid modified filler with a high heat conductivity coefficient and a liquid metal, and then adding the solid-liquid mixed filler into organic silicon gel. By utilizing the synergistic effect of the three fillers, the high heat conductivity and insulativity of the heat-conducting gel are realized, the heat conductivity coefficient of the prepared gel material is greater than 6.5 W / (m.K), and the volume resistivity is greater than 109 omega.cm; the preparation method of the insulating high-thermal-conductivity gel is simple and low in equipment requirement, and the prepared gel material is excellent in performance and suitable for industrial continuous and mass production.

The invention discloses a hot-melt double-sided adhesive tape and a preparation process thereof, and belongs to the technical field of double-sided adhesive tapes, the double-sided adhesive tape comprises a hot-melt adhesive layer and a release film, and the hot-melt adhesive layer is obtained by coating a hot-melt adhesive on the release film and then drying; the hot melt adhesive comprises the following raw materials in parts by weight: 80-95 parts of matrix resin, 10 parts of tackifying resin and 10-20 parts of modified magnetic boron nitride, the preparation method comprises the following steps: weighing a hot melt adhesive raw material, adding a solvent, preparing a hot melt adhesive solution with the solid content of 20-40wt%, coating one surface of the release film with the hot melt adhesive solution, and drying under the action of an external uniform magnetic field. The hot melt adhesive layer contains modified magnetic boron nitride, and is directionally arranged on the surface of the release film under the action of a magnetic field in the preparation process of the hot melt adhesive layer, so that the interface thermal resistance is reduced, the heat-conducting property of the coating is remarkably improved, and the heat dissipation performance of the lithium battery is improved.

The invention relates to the technical field of preparation of heat-conducting materials, in particular to a preparation method of a graphene metal heat-conducting gasket, which comprises the following specific steps: S1, pretreatment of graphene, S2, plasma treatment of graphene, S3, preparation of a metal substrate, S4, nano-particle deposition of the metal substrate, S5, compounding of graphene and the metal substrate, and S6, post-treatment. According to the method, the graphene is subjected to plasma treatment, and the nanoparticles are deposited on the surface of the metal substrate, so that the bonding strength of the graphene and the metal is greatly improved, the interface thermal resistance is effectively reduced, heat can be transferred between the graphene and the metal more smoothly, and the heat transfer efficiency is improved. The heat generated in the operation process of the electronic equipment can be conducted out more quickly, the problem of local overheating is effectively avoided, the stability and reliability of the equipment are greatly improved, and the service life of the equipment is prolonged.

The invention provides a preparation method of a fiber composite photovoltaic support material, and belongs to the technical field of composite materials. The fiber composite photovoltaic support material is prepared by adding the modified basalt fiber as a composite reinforcing material and then introducing the polyisocyanurate tripolymer and the modified aluminum nitride, and the support material is high in longitudinal tensile strength and has good flame retardant property and heat-conducting property.

The invention provides a radiation cooling and heat conducting polyether-ether-ketone composite material and a preparation method and application thereof.The preparation method of the composite material comprises the specific steps that S1, boron nitride is subjected to high-temperature calcination and furnace cooling, and hydroxyl modified boron nitride is obtained; s2, dispersing aramid staple fibers in a poor solvent, and performing high-speed shearing to form microspheres, namely aramid fiber balls; s3, uniformly mixing the aramid fiber balls obtained in S2 with polyether-ether-ketone powder, then adding the hydroxyl modified boron nitride obtained in S1, and continuously and uniformly mixing to obtain a composite material dispersion; and S4, carrying out melting and hot pressing on the composite material dispersion obtained in S3 to obtain the target polyether-ether-ketone composite material. The preparation method of the material disclosed by the invention is simple, and the prepared polyether-ether-ketone composite material shows excellent radiation cooling performance, heat-conducting property and heat stability and has a wide application prospect.

The invention provides a back contact photovoltaic cell piece capable of preventing stacking scratch in a high-temperature passivation process. The back contact photovoltaic cell piece comprises a back contact photovoltaic cell piece body and a plurality of soft isolation protrusions located on the light receiving face of the back contact photovoltaic cell piece body. The soft isolation protrusions are used for supporting photovoltaic cells to be mutually isolated when the photovoltaic cells are stacked layer by layer, and the soft isolation protrusions are resistant to high temperature of 300 DEG C and do not become sticky or yellow within 3 hours. According to the invention, the soft isolation projections are arranged on the light receiving surface of the back contact photovoltaic cell sheet body to support mutual isolation of the photovoltaic cell sheets when the photovoltaic cell sheets are stacked layer by layer, so that the photovoltaic cell sheets can be protected from being scratched in the stacking and moving process; the flexible isolation protrusions are arranged on the back contact photovoltaic cell piece, the flexible isolation protrusions can be prevented from scratching the surface of the photovoltaic cell piece due to the specific flexibility of the flexible isolation protrusions, meanwhile, the flexible isolation protrusions can bear the passivation temperature of 300 DEG C or above and do not crack or yellow or adhere to the cell piece, and therefore it can be ensured that the back contact photovoltaic cell piece is subjected to high-temperature passivation in a multi-layer stacking mode, and the passivation efficiency is improved.

The invention relates to the technical field of epoxy resin, and discloses a polyarylamide modified boron nitride-epoxy resin composite material, hydroxylated nano boron nitride reacts with a diazo group of 4-diazo diphenylamine sulfate to obtain aminated nano boron nitride, the aminated nano boron nitride and a 3, 5-diaminobenzoic acid monomer are subjected to a polymerization reaction to obtain polyarylamide modified boron nitride, and the polyarylamide modified boron nitride-epoxy resin composite material is prepared through the following steps: reacting hydroxylated nano boron nitride with a diazo group of 4-diazo diphenylamine sulfate; the polyarylamide modified boron nitride has good compatibility with epoxy resin, amino-terminated groups can be subjected to ring-opening reaction with epoxy groups of the epoxy resin, nano boron nitride is organically combined with the epoxy resin under the bridging action of polyarylamide, covalent bonds formed between a large number of amino groups on the surface and the epoxy resin in the curing process, and the epoxy resin can be cured to form the epoxy resin. The interface thermal resistance of the filler and the epoxy resin is reduced, the superhigh resistivity of the nano boron nitride, the reduction of agglomeration and the modification of the filler enable the polyarylamide modified boron nitride-epoxy resin composite material to show excellent thermal conductivity.

The invention relates to heat-conducting silicone grease with synergistic effect of modified hexagonal boron nitride and graphene nanoribbons and a preparation method of the heat-conducting silicone grease. Comprising the following steps: (1) modifying hexagonal boron nitride by using gamma-aminopropyltriethoxysilane, so as to obtain gamma-aminopropyltriethoxysilane modified hexagonal boron nitride; and (2) uniformly mixing gamma-aminopropyltriethoxysilane modified hexagonal boron nitride, graphene nanobelts and polydimethylsiloxane, carrying out ball milling, and carrying out vacuum centrifugal defoaming to obtain the heat-conducting silicone grease with the synergistic effect of the modified hexagonal boron nitride and the graphene nanobelts. Through gamma-aminopropyltriethoxysilane modification, the dispersity and interface bonding force of boron nitride in polydimethylsiloxane are improved, the problem that the hydrophilicity of boron nitride is incompatible with a matrix is effectively solved, the compatibility of boron nitride and polydimethylsiloxane is improved, a heat conduction network is effectively constructed, and the heat conduction efficiency is improved. And the graphene nanobelt and boron nitride generate a synergistic effect, so that the interface thermal resistance is greatly reduced.

The present invention relates to the technical field of thermally conductive polyester films, and specifically to a flexible high thermal conductivity graphene-filled polyurethane composite film and a preparation method thereof. Conventional graphene-modified polyurethane thermally conductive films have good horizontal thermal conductivity, but poor vertical thermal conductivity. In view of the above problems, the present invention provides a flexible high thermal conductivity graphene-filled polyurethane composite film, wherein the material system contains graphene, carbon quantum dots and a one-dimensional film-forming agent at the same time, and the graphene, carbon quantum dots and the one-dimensional film-forming agent are interconnected, interspersed and stacked to form a complex three-dimensional network structure, and the filler particles are distributed more evenly and densely in the polyurethane resin matrix, which significantly improves the thermal conductivity of the obtained flexible high thermal conductivity graphene-filled polyurethane composite film.

The invention relates to a preparation method of a diamond / copper composite material, which comprises the steps of ingredient mixing and hot pressed sintering: preparing copper powder, metal Ti / nonmetal carbide and Cr or Mn powder into a base material, and uniformly mixing large-particle diamond and small-particle diamond to prepare a reinforcing body filling material; then the base material and the reinforcement filling material are taken and placed in a container to be mixed, after mixing, grinding is conducted in the environment of vacuumizing and filling of high-purity argon, and mixture powder is obtained; and the mixture powder is subjected to vacuumizing hot pressing sintering, then in the vacuum state, a heating system is closed, natural cooling is conducted, high-purity nitrogen is charged into a sintering furnace cavity, the cavity is opened after the pressure inside and outside the cavity is equal, and the diamond / copper composite material is obtained. According to the method provided by the technical scheme, the problems that the cost is high, the heat conductivity is low, diamond particles are not uniformly dispersed in the composite material and the diamond particles fall off due to poor wetting when the diamond / copper composite material is prepared by a metal permeation technology can be effectively solved.

The invention belongs to the technical field of polymer-based heat-conducting interface materials, and particularly relates to a nano-silver modified carbon fiber coated organic silicon heat-conducting composite material as well as a preparation method and application thereof. The preparation method comprises the following steps: modifying oxidized pitch-based carbon fibers by using a silane coupling agent to obtain silane coupling agent modified carbon fibers, fixing nano-silver on the silane coupling agent modified carbon fibers to obtain nano-silver modified carbon fibers, and filling the nano-silver modified carbon fibers into organic silicon to obtain the nano-silver modified carbon fiber-organic silicon heat-conducting composite material. Under the low filling amount of the heat-conducting filler, the asphalt-based carbon fiber is modified by adopting the silane coupling agent and the nano-silver, so that the dispersity of the asphalt-based carbon fiber in organic silicon is improved, the heat-conducting property of the asphalt-based carbon fiber can be improved by fixing the nano-silver, the interface thermal resistance between the asphalt-based carbon fiber filler is reduced, and the thermal conductivity of the asphalt-based carbon fiber is improved. The heat-conducting property of the nano-silver modified carbon fiber coated organic silicon heat-conducting composite material is greatly improved.

The invention discloses a semi-cured adhesive insulating film, a preparation method, application and a use method thereof. The semi-cured adhesive insulating film comprises an upper organic silica gel layer, a lower organic silica gel layer and a middle polyimide film, wherein the upper organic silica gel layer and the lower organic silica gel layer are filled with heat-conducting filler; the organic silica gel layer is prepared from the following components in parts by weight: 6 to 8 parts of high-viscosity liquid organic silicon rubber, 2 to 3 parts of low-viscosity liquid organic silicon rubber, 0.5 to 0.8 part of hydrogen-containing silicone oil, 0.1 to 0.5 part of an inhibitor, 0.1 to 0.2 part of a platinum catalyst, 0.1 to 0.3 part of a silane coupling agent, 0.1 to 0.3 part of an organic silicon tackifier and 10 to 20 parts of nano spherical boron nitride powder; and 20-40 parts of aluminum nitride powder. The semi-cured insulating adhesive film is prepared by compositely filling the organic silica gel layers of the heat-conducting filler on the two surfaces of the polyimide film, and is small in occupied space, simple in assembly process, high in insulating reliability and low in use cost.

The invention discloses a heat-conducting aramid insulation paper-based material as well as a preparation method and application thereof. The preparation method of the heat-conducting aramid insulation paper-based material comprises the following steps: (1) introducing amino groups on the surfaces of boron nitride nanosheets to obtain aminated boron nitride nanosheets; (2) dissolving m-phenylenediamine in N, N-dimethylacetamide, then adding m-phthaloyl dichloride, then adding the amino boron nitride nanosheets, and carrying out a reaction to obtain a heat-conducting aramid polymer solution; (3) performing wet spinning on the heat-conducting aramid polymer solution to obtain heat-conducting aramid fibers; and (4) mixing the heat-conducting aramid fiber and the fibrid, and manufacturing the heat-conducting aramid insulation paper-based material. The amino boron nitride nanosheets are connected with amide groups among aramid macromolecules, so that the interfacial compatibility of the filler and the base material in the paper material is improved, and the strength and the heat-conducting property of the paper material are improved.

The invention relates to the technical field of nano composite materials, in particular to a composite heat-conducting, insulating and flame-retardant thermal interface material and a preparation method thereof.The composite heat-conducting, insulating and flame-retardant thermal interface material is prepared from, by weight, 1-25% of BN-DTPMPA-Cu < 2 + > filler and 1-25% of polyethylene glycol terephthalate (PET) through blending extrusion, film forming and pressing, and the content of the BN-DTPMPA-Cu < 2 + > filler is 1-25%. The composite heat-conducting, insulating and flame-retardant thermal interface material has good application prospects in the heat dissipation fields of electronic devices, LEDs and the like, meanwhile, the PET / BN-DTPMPA-Cu < 2 + > composite heat-conducting, insulating and flame-retardant thermal interface material is good in environmental protection property and easy to prepare, and the application safety and universality of high polymer materials are greatly improved.

The utility model provides a high thermal conductivity diamond IGBT heat radiation structure, comprising a diamond layer and an IGBT layer, one surface of the diamond layer is provided with a copper layer, at least one surface of the IGBT layer is provided with the diamond layer covered with the copper layer, and the IGBT layer is attached and connected with a part of the copper layer. According to the invention, by using the excellent thermal conductivity, insulativity and chemical inertness of the diamond, a novel IGBT packaging form is designed, and the heat dissipation performance of the IGBT is effectively improved; and the IGBT is directly electrically connected with the diamond layer and the copper layer, so that the heat dissipation efficiency of the IGBT is greatly improved. Compared with an existing ceramic substrate such as aluminum nitride and silicon nitride needing to add a bottom plate to be connected with a cooling device, the surface of the diamond is in direct contact with the cooling liquid, the interface thermal resistance is reduced, the heat dissipation efficiency is improved, and the heat dissipation efficiency is improved by more than 20% according to experimental results; and the IGBT can adopt more compact design during design, so that the final volume is reduced by more than 1 / 10 relative to the original volume.

The invention discloses a surface plasmon resonance radiation cooling-heat conduction-liquid film evaporation coupling heat dissipation multi-layer co-construction micro-nano structure and a manufacturing method and application thereof, and belongs to the technical field of micro-nano manufacturing and functional structure surfaces, and the multi-layer co-construction micro-nano structure is composed of three layers of structures; the bottom layer structure is a substrate; the top of the bottom layer structure is a near-infrared wavelength scale grating structure; the middle-layer structure is a high-thermal-conductivity diamond film and covers and fills the bottom-layer structure; the top of the middle-layer structure is of a lyophilic micro-nano structure; the top layer structure is a silicon dioxide film. Radiation cooling, efficient heat conduction and liquid film evaporation / boiling phase change heat transfer are coupled, the heat transfer and heat dissipation level is greatly improved, additional external energy input is not needed, and positive significance is achieved for research and development of a novel high-performance and zero-energy-consumption radiator, promotion of development of a high-heat-flow-density advanced system and improvement of the ecological environment.

The invention discloses an aerosol generating product and an aerosol generating system.The aerosol generating product comprises an aerosol forming base material sheet and a magnetic heating body sheet, and the magnetic heating body sheet and the aerosol forming base material sheet are arranged in a stacked mode in the thickness direction and attached in the stacked area in a surface contact mode; the main heat conduction path directed from the magnetic heating element sheet to the aerosol-forming substrate sheet is a path passing through the thickness direction of the laminated region. Compared with the prior art, the magnetic heating body sheet and the aerosol forming base material sheet are laminated along the thickness direction, and the surface contact is realized in the lamination area, so that the main conduction path of heat from the magnetic heating body sheet to the base material is a short path passing through the lamination thickness direction; therefore, heat conduction distance is shortened, interface thermal resistance is reduced, and heating response speed and energy utilization rate are improved. And meanwhile, the base material is heated more uniformly, so that the aerosol generation efficiency and consistency are improved, and the risk caused by local overheating is reduced.

This invention discloses a high thermal conductivity PCB metal substrate and its preparation method, relating to the field of PCB manufacturing technology. The high thermal conductivity PCB metal substrate of this invention comprises at least a metal base layer and a thermally conductive dielectric layer; the thermally conductive dielectric layer comprises at least the following raw materials in parts by weight: 100 parts of 1,5-naphthol modified epoxy resin; 20-35 parts of bismaleimide; 10-25 parts of diallyl biphenyl ester; 20-50 parts of cyanate ester; 20-50 parts of bismaleimide-coated aluminophosphate passivated aluminum nitride@boron nitride composite thermally conductive filler; 5-15 parts of bismaleimide-octavinyl cage-type polysilsesquioxane composite porous microspheres; 20-35 parts of curing agent; and 0-10 parts of diluent. The PCB metal substrate prepared by this invention possesses high thermal conductivity, low dielectric constant, high interfacial peel strength, and excellent heat resistance.

The invention relates to a spherical boron nitride (at) ZIFs derived carbon nanotube heterostructure material and a preparation method and application thereof.The preparation method of the heterostructure material comprises the steps that hexagonal boron nitride (h-BN) is subjected to ultrasonic treatment in Zn < 2 + > and Co < 2 + > metal ion solutions, metal ion intercalation assists in stripping the h-BN, and obtained h-BN nanosheets are spontaneously curled and assembled into spherical boron nitride C-BN; the preparation method comprises the following steps: firstly, preparing C-BN, then adding 2-methylimidazole, growing MOFs particles (ZIF) on the surface of the C-BN in situ to obtain a C-BN-ZIF precursor, physically grinding and mixing the C-BN-ZIF precursor with melamine, performing high-temperature calcination, and growing ZIF carbonized derived carbon nanotubes on the surface of the C-BN in situ to obtain the spherical boron nitride-ZIF derived carbon nanotube heterostructure material C-BN-ZnCo-ZCNT. The spherical nanofiller is simple and easy to prepare, raw materials are cheap and easy to obtain, operation is easy, the spherical nanofiller serves as a heat conduction filler, a three-dimensional heat conduction network is easily formed in a composite material, adjacent filler is bridged through the carbon nanotubes to reduce interface thermal resistance, and the spherical nanofiller has good application prospects in thermal interface materials.

This invention relates to the field of special ceramics preparation technology, and discloses a process for preparing high thermal conductivity ceramic materials for high-nickel ternary cathode sintering, including: preparing magnesium aluminum spinel green blanks containing magnesium oxide, yttrium oxide and titanium oxide composite additives; performing cyclic variable oxygen pressure sintering at 1420℃ to 1480℃, controlling the furnace atmosphere to periodically switch between the first and second oxygen partial pressure states. This invention utilizes the oxygen potential difference to drive the grain boundary liquid phase to alternate between low viscosity wetting and high viscosity pinning characteristics, eliminating the rheological quiescent zone at the end of sintering, effectively suppressing abnormal grain growth while ensuring high material density, and improving the thermal conductivity and lithium erosion resistance of the ceramic sagger.

The invention discloses a zirconium-based fuel cladding surface corrosion-resistant interface integrated ZrxO / SiC multilayer composite coating and a preparation method thereof. The method comprises the following steps: 1, pre-oxidizing a zirconium-based fuel cladding to grow a ZrxO oxide film in situ; 2, performing Ar plasma sputtering activation on the pre-oxidized zirconium-based fuel cladding; and 3, alternately depositing to form the SiC composite coating with a multi-layer structure. According to the preparation method, pre-oxidation and magnetron sputtering deposition are combined, and the gradient composite structure coating from ZrxO in-situ growth of the matrix Zr to the surface SiC composite coating is constructed, so that the thermal mismatch and interface thermal resistance of matrix metal and the ceramic coating are reduced, the interface adaptability of the matrix and the SiC composite coating is enhanced, and by means of the high corrosion resistance, high heat conductivity and high hardness of the SiC composite coating, the thermal conductivity of the matrix metal and the surface SiC composite coating is improved. The improvement of surface corrosion resistance and wear resistance of the fuel cladding under normal and accident working conditions is synchronously realized, and the fault-tolerant capability of the zirconium-based cladding under the accident state is optimized.

The application provides a high-thermal-conductivity diamond / copper composite material and an SPS sintering process thereof, raw material pretreatment: selecting three kinds of monocrystalline diamond particles with different particle sizes, mixing the titanium-plated diamond obtained after vacuum titanium plating treatment; solid dry powder mixing: uniformly mixing a solid additive and graphene modified copper powder to prepare a copper-based composite dry powder; nitrogen intermittent airflow suspension dispersion: adding the titanium-plated diamond into a sealed covering tank to make the titanium-plated diamond suspended and dispersed in the sealed covering tank; atomization covering makes the copper-based composite dry powder uniformly covered on the surface of the titanium-plated diamond to obtain composite particles; vacuum low-temperature degreasing to obtain the composite particles after degreasing, and SPS sintering demolding to obtain the high-thermal-conductivity diamond / copper composite material. The coating is uniform and dense, has no exposure and no agglomeration, and significantly reduces porosity and interface thermal resistance; the proportioning is accurate, the degreasing is thorough, and there is no residue; the generation of brittle phases is inhibited, and the interface combination is excellent; the thermal conductivity is stable and greater than 700 W / (m*K), and the density is greater than or equal to 99%.

The invention provides a method for preparing an ultrathin SiC / diamond composite wafer by Van der Waals force bonding. The method comprises the following steps: forming a graphene layer on one surface of a polycrystalline diamond wafer to obtain a diamond / graphene wafer; forming a graphene layer on one surface of the SiC wafer to obtain a SiC / graphene wafer; h < + > ions are injected into the SiC surface of the SiC / graphene wafer through ion injection; bonding the polycrystalline diamond and the SiC by virtue of the graphene layers of the polycrystalline diamond and the SiC through Van der Waals force bonding to obtain a bonded wafer; stripping the SiC layer of the bonded wafer at high temperature to obtain an ultrathin SiC / diamond composite wafer; and polishing the surface of the SiC layer of the ultrathin SiC / diamond composite wafer. According to the method for preparing the ultrathin SiC / diamond composite wafer through Van der Waals force bonding, low voidage and large-size bonding of diamond and silicon carbide can be achieved, the interface thermal resistance between the diamond and a device can be reduced, and the output power density of the device can be improved.

The invention discloses a diamond filler for chip heat dissipation and a preparation method thereof, and belongs to the technical field of heat conduction fillers, the diamond filler comprises the following raw materials by weight: 90-100 parts of pretreated functional diamond, 4-8 parts of modified carbon nanotubes and 15-25 parts of modified hexagonal boron nitride nanoparticles; the diamond filler for chip heat dissipation is prepared by mixing pretreated functional diamond, modified carbon nanotubes and modified hexagonal boron nitride nanosheets, adding the mixture into N-methyl pyrrolidone, adding 1-ethyl-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide, and carrying out a reaction. According to the mode, micro-grinding rounding and dopamine functionalization of the diamond, carbon nano tube modification and hexagonal boron nitride modification have a synergistic gain effect on the filler heat conductivity, composite material heat conductivity and composite material CTE of the prepared diamond filler.

The preparation method comprises the following steps: carrying out lipophilic modification on the surfaces of boron nitride, carbon nanotubes and aluminum nitride by using a silane coupling agent; the preparation method comprises the following steps: adding boron nitride, carbon nanotubes and aluminum nitride subjected to surface treatment into methyl vinyl silicone oil, and fully dispersing by adopting a high-speed shearing machine; mixing the dispersed methyl vinyl silicone oil with polyether modified silicone oil and aminopropyltriethoxysilane, stirring in a vacuum environment by using a planetary stirrer, and gradually adding benzoyl peroxide and vinyl-terminated polydimethylsiloxane in the vacuum stirring process; placing the mixture in a vacuum degassing device, and carrying out multiple degassing operations; and pouring the degassed mixture into a Teflon coating mold, vibrating to remove residual bubbles, and carrying out step-by-step temperature curing in a temperature control oven. The overall heat-conducting property of the material is remarkably improved, and the mechanical strength and the heat-conducting property of a final product are improved.

The application relates to the technical field of semiconductors, and particularly discloses a POI substrate, a preparation method thereof and an acoustic device. The preparation method of the POI substrate comprises the following steps: providing a substrate; growing an amorphous gallium oxide layer on the substrate; and growing a nanocrystalline gallium oxide layer on the amorphous gallium oxide layer; wherein the nanocrystalline gallium oxide layer is c-axis oriented perpendicular to a section; the nanocrystalline gallium oxide layer is subjected to activation treatment to obtain a first intermediate product; a piezoelectric substrate is subjected to ion implantation to form a peeling defect layer at a preset position of the piezoelectric substrate, thereby obtaining a second intermediate product A; the first intermediate product is bonded with the second intermediate product A to obtain a third intermediate product A; the third intermediate product A is treated by using a pulse laser to convert the nanocrystalline gallium oxide layer into an epsilon-phase gallium oxide layer; and the piezoelectric substrate is split and partially peeled along the peeling defect layer to form a piezoelectric layer. By implementing the application, the heat conduction performance and reliability of the POI substrate can be improved.