6874 results about "Thermal conductivity" patented technology

The invention discloses a high-strength and high-toughness aluminum nitride ceramic and a preparation method thereof, and relates to the technical field of ceramics, a sol-gel method is adopted to coat the surface of aluminum nitride with a stable shell layer to form a core-shell structure, meanwhile, the low lattice mismatch rate of a core-shell interface is utilized to reduce thermal resistance, and toughness and thermal conductivity are both considered; according to the external magnetic field tape casting method, the magnetic dipole moment orientation principle is utilized, an external magnetic field is applied in the tape casting stage, the in-plane mechanical property is improved, and the fracture toughness is improved through the magnetism of aluminum nitride whiskers; a reinforcement is introduced to improve the mechanical property and corrosion resistance of the aluminum nitride ceramic material, multi-granularity powder is compounded, large-particle aluminum nitride powder is used as a sintering and heat-conducting framework material, and high activity provided by submicron particles is utilized to promote sintering, so that the sintering temperature of aluminum nitride can be remarkably reduced, and the performance is greatly improved; and the aluminum nitride substrate expands more application fields on a future packaging circuit.

The invention discloses a multi-dimensional data-based temperature prediction method and system for a power integrated module, particularly relates to the technical field of temperature measurement, and is used for solving the problems of temperature field distortion and unreliable measurement result caused by thermal disturbance introduced by a sensor in temperature monitoring of an existing power integrated module. Multi-dimensional temperature data are formed by acquiring measurement data of a plurality of temperature sensors, a virtual heat flow path is reconstructed based on temperature gradient distribution, deviation degree analysis is carried out on the virtual heat flow path and an inherent structure heat flow path of a module so as to judge thermal disturbance influence, and reference isothermal surface topological structure features are acquired when disturbance occurs. A real-time isothermal surface is constructed, a thermal disturbance space position and an influence range are identified by detecting a curvature distribution sudden change area, a local thermal conductivity correction field is established to perform thermal field reconstruction on multi-dimensional temperature data to generate correction temperature field data, and finally a temperature change trend is analyzed according to the correction temperature field data to predict a future temperature state.

The invention provides a copper-steel composite heat pipe and a preparation method thereof, and relates to the technical field of heat pipes, the copper-steel composite heat pipe comprises a steel-copper composite pipe, and the steel-copper composite pipe is composed of a copper inner pipe and a steel outer pipe. An internal copper structure is arranged in the steel-copper composite pipe; the internal copper structure is copper powder or a copper wire mesh. The copper powder is unilateral copper powder or bilateral copper powder or ring copper powder; the copper wire mesh is a copper mesh, or a copper mesh and a copper wire capillary, or a copper wire capillary. The steel outer pipe is made of steel 316L, and the copper inner pipe is made of copper C1020. The copper-steel combined material is used, the cost is saved, and it is guaranteed that materials are saved in the whole heat dissipation field. The double-layer combination of the copper inner pipe (C1020, high heat conduction) and the steel outer pipe (316L, corrosion resistance and high strength) is adopted, the efficient heat conduction of copper is utilized, and the environment erosion resistance and mechanical impact resistance of steel are utilized, so that the heat pipe is adaptive to complex working conditions (such as industrial high-temperature, humid or corrosion risk scenes), and the service life of the heat pipe is prolonged.

Systems, assemblies, apparatuses, and methods herein may provide an enhanced fluid seal between two components. A seal to enhance a fluid seal between a surface of a first component of a pump and a surface of a second component of the pump may include an annular seal body having a seal body surface and a seal cross-section at least partially defined by the seal body surface. The annular seal body may include a metal mesh, thereby to enhance thermal conductivity between the seal and one or more of the first component or the second component, so as to transfer heat from the seal to one or more of the first component or the second component, thereby to reduce a temperature of the seal and extend a service life of the seal.

The invention discloses an earth heat flow joint inversion calculation method, device and system, and a storage medium. The method comprises the following steps: 1, obtaining a temperature constraint value; 2, obtaining a thermal parameter constraint value; 3, determining value ranges of thermal conductivity and heat generation rate parameters of each layer section; 4, constructing an initial temperature profile; 5, carrying out inversion optimization to obtain an optimal thermal parameter; and 6, calculating and extracting an earth heat flow value. By adopting the technical scheme of the invention, a high-precision and high-reliability earth heat flow value can be obtained under the constraint of a small amount of measured data.

The invention belongs to the technical field of building energy conservation, and provides a real-time inversion method and system for a heat transfer coefficient of a building envelope, and the method comprises the steps: obtaining surface parameters and environment parameters of the building envelope; based on the obtained parameters and the physical neural network model, taking the minimum joint loss function based on the physical mechanism as a target, and performing inversion to obtain the optimal heat conductivity coefficient of the building envelope; and calculating the heat transfer coefficient of the building envelope according to the obtained optimal heat conductivity coefficient of the building envelope, and completing real-time inversion of the heat transfer coefficient of the building envelope.

The invention belongs to the field of materials, and particularly relates to a composite thermal interface material and a preparation method thereof. The preparation method comprises the following steps: plating non-reactive metal, non-reactive metal carbide or non-reactive ceramic on the surface of diamond micro powder, inducing lattice defects on the surface of a plating layer and alloying a local interface by combining a mechanical force field, and defoaming to obtain the composite thermal interface material. The composite thermal interface material has high thermal conductivity and long-term stability, and the contradiction between excessive alloying of a traditional reactive coating and high interface thermal resistance of a non-reactive coating is solved. The method is particularly suitable for the field of thermal management of high-end electronic devices such as 5G chips and power modules.

The invention discloses a silica gel pad with high thermal conductivity and heat resistance and a preparation method thereof, and the method comprises the following steps: preparing a composite thermal conductive filler, mixing boron nitride nanosheets and graphene according to a certain mass ratio, adding a silane coupling agent, carrying out ball milling, adding spherical alumina, and mixing; preparing modified organic silicon resin, wherein methyl vinyl silicone rubber, hydrogen-containing silicone oil, a platinum catalyst and MQ silicon resin react to obtain the modified organic silicon resin; mixing and defoaming the modified organic silicon resin, the composite heat-conducting filler, the flame retardant and the antioxidant to obtain a heat-conducting silica gel mixture; preparing a reinforced base material, carrying out plasma treatment on glass fiber cloth, and then impregnating the glass fiber cloth with vinyl ester resin for pre-curing; and grinding the mixture by three rollers, coating the mixture on a reinforced base material, and heating and curing. The thermal conductivity of the obtained silica gel pad is 2.5-3.5 W / m.K, the volume resistivity is larger than 1012 omega.cm, the long-term heat-resistant temperature reaches 200 DEG C or above, the tensile strength is larger than 5 MPa, the peel strength is larger than 15 N / cm, and the silica gel pad has excellent thermal conductivity, insulativity, heat resistance and mechanical strength.

The invention discloses a light-moisture dual-curing underwater epoxy coating with a self-repairing function as well as a preparation method and a construction method of the light-moisture dual-curing underwater epoxy coating. The epoxy coating comprises a component A and a component B, wherein the mass ratio of the component A to the component B is (1.5-3.5): 1; the component A is prepared from the following raw materials: bisphenol F type epoxy resin, dynamic disulfide bond modified polysulfide rubber, boron nitride nanosheet and silicon carbide nanowire hybrid filler, a photoinitiator and a silane coupling agent; the component B is prepared from the following raw materials: moisture-cured polyether amine, a boric acid ester bond cross-linking agent and hydrophobic modified graphene oxide. According to the invention, a light-moisture dual-curing mechanism is adopted, ultraviolet irradiation initiates rapid surface curing, and then environmental moisture permeates to complete deep curing. The material provided by the invention has the advantages of rapid curing, excellent self-repairing function, significantly improved underwater adhesion and good thermal conductivity, and provides a new solution for rapid repairing and long-acting protection of underwater structures.

The invention discloses a flexible heat-conducting composite material with chain-shaped boron nitride and a preparation method, and belongs to the technical field of flexible electronic device heat management materials, the flexible heat-conducting composite material comprises an elastomer matrix and a magnetic functionalized boron nitride filler filled in the elastomer matrix; the elastomer matrix is polydimethylsiloxane; the magnetic functionalized boron nitride filler is prepared by modifying Fe3O4 nanoparticles on the surface of a boron nitride sheet; the boron nitride sheets form a vertically arranged chain structure in the elastomer matrix. The chained vertical arrangement of the boron nitride sheets is realized by prolonging the magnetic field treatment time, the Fe3O4 modification quantity is controlled to optimize the balance between the magnetic responsiveness and the heat-conducting property, a chained heat-conducting network connected end to end is formed, and the thermal seepage threshold value is reduced. According to the flexible composite material and the preparation method thereof, boron nitride sheets are induced to be vertically arranged through a magnetic field to form a chain-shaped heat-conducting network, so that high heat conductivity under low filler loading capacity is realized, and excellent stretchability is kept at the same time.

The invention provides a manufacturing method of an ultra-low dielectric loss high-speed copper-clad plate, which comprises the following steps of: constructing a physical coupling model of a multi-zone independent temperature control module and an electro-thermal conductivity adjusting layer based on the thickness of the copper-clad plate and a thermal response parameter of a resin system; space and time dynamic distribution of heating area power and heat conductivity is achieved; a dynamic thermal boundary regulation and control algorithm, finite element simulation and self-adaptive PID feedback are fused, real-time monitoring and deviation compensation of a temperature field are carried out through infrared thermal imaging and edge calculation, heating and heat dissipation strategies are cooperatively adjusted, a heat flow path can be actively guided, the uniformity of thermal stress distribution and the structural stability are achieved, and the method is suitable for large-scale popularization and application. And the thermal management efficiency of the copper-clad plate in a complex manufacturing environment is improved.

The invention discloses a silicon nitride ceramic-based composite material and a preparation method thereof, and relates to the technical field of silicon nitride ceramics. The silicon nitride ceramic-based composite material is prepared from silicon dioxide coated modified boron nitride and resin composite phase change microcapsules, Si3N4-C coated Al2O3 core-shell fiber aerogel, nano yttrium oxide and polyvinyl butyral, the silicon dioxide coated modified boron nitride and resin composite phase change microcapsules are stably attached to the surface of the Si3N4-C coated Al2O3 core-shell fiber aerogel in a chemical bonding and mechanical interlocking mode, the interface bonding strength is enhanced, the risk of phase separation is reduced, the combination effect of the silicon dioxide coated modified boron nitride and resin composite phase change microcapsules and the Si3N4-C coated Al2O3 core-shell fiber aerogel is better exerted, and the composite phase change effect of the silicon dioxide coated modified boron nitride and resin composite phase change microcapsules is improved. According to the present invention, the fracture toughness can be improved through fiber toughening, aerogel pore and microcapsule stress dispersion, the high temperature resistance can be improved through the low thermal conductivity of the aerogel and the heat absorption effect of the microcapsule, the mechanical property of the silicon nitride can be significantly improved through multiple ways and multiple modes, and the high temperature resistance can be effectively enhanced.

The invention provides a well wall heat insulation hollow microsphere and a preparation method thereof. A sealed vacuum cavity is formed in the well wall heat insulation hollow microsphere, a polymer layer is arranged on the surface of the well wall heat insulation hollow microsphere, the polymer layer is provided with cationic groups and anionic groups, and aerogel nano powder is embedded in the polymer layer. The invention also provides a preparation method of the well wall heat insulation hollow microsphere. The well wall heat insulation hollow microspheres have high compressive strength, and the heat conductivity coefficient is reduced; efficient well wall adsorption can be achieved through the synergistic effect of anion groups and cation groups, the defects that a traditional heat insulation material is prone to breaking, fast in heat conduction and ineffective in adsorption under the high-temperature and high-pressure environment of an ultra-deep well are overcome, and the material is suitable for an ultra-deep and ultra-deep oil and gas well drilling fluid system. A multistage pore heat insulation system is constructed through the zwitterionic polymer and the aerogel nano-powder, and a rough surface structure can be provided to assist the microspheres in adsorbing well wall rocks.

The invention relates to the technical field of model construction, in particular to a geothermal field three-dimensional model construction method based on point cloud data, and the method comprises the steps: synchronously collecting a surface laser radar point cloud, an underground sound wave point cloud and a rock core scanning point cloud, the underground sound wave point cloud comprising signal attenuation coefficient data; performing cover layer signal compensation on the enhanced point cloud data set, inverting a permeability field based on rock core fracture characteristics, and outputting a shadow correction point cloud data set; and inputting the shadow correction point cloud data set into a permeability constraint modeling algorithm to generate a three-dimensional geologic model comprising a heat storage top interface and dynamic permeability distribution. By introducing a three-dimensional voxel modeling method based on point cloud data, the precision and resolution of structural modeling of the heat storage area are effectively improved, an equivalent heat conductivity model for average permeability adjustment and a Darcy flow velocity item are fused, a heat flow evolution equation set refined to a voxel level is constructed, and the modeling precision and resolution of the heat storage area structure are improved. And the depicting capability of the heat flow behavior of the high-temperature gradient region is obviously improved.

The invention relates to the technical field of crystal material preparation, in particular to a layered selenide Ge3Sb2Se5 semiconductor material and a preparation method thereof. The preparation method of the layered selenide Ge3Sb2Se5 semiconductor material comprises the following steps: grinding a Ge3Sb4Se7 material, putting the ground Ge3Sb4Se7 material into a quartz tube, adding iodine particles, performing vacuum packaging in the quartz tube, putting one end, with raw materials, of the quartz tube into a high-temperature region, and putting one end, without raw materials, of the quartz tube into a low-temperature region; raising the temperature to 400 + / -25 DEG C at the low-temperature region end and 500 + / -25 DEG C at the high-temperature region end, preserving heat for 7 days, and naturally cooling to room temperature to obtain the Ge3Sb2Se5 semiconductor material. The crystal structure of the Ge3Sb2Se5 semiconductor material belongs to an orthorhombic system, and the Ge3Sb2Se5 semiconductor material has the characteristics of low thermal conductivity and low resistivity. According to the preparation method disclosed by the invention, the Ge3Sb2Se5 semiconductor material can be stably prepared, and a material is provided for physical property research of the Ge3Sb2Se5 semiconductor material and preparation of semiconductor photoelectric devices and the like.

The invention relates to the technical field of machine learning potential molecular simulation, and provides a montmorillonite thermal conductivity prediction method based on NEP machine learning potential, and the method comprises the following steps: constructing a montmorillonite crystal structure model, carrying out first principle molecular dynamics calculation on the montmorillonite crystal structure model, introducing lattice distortion and atomic disturbance, and generating an initial structure set; performing static single-point DFT calculation on the initial structure set, and constructing a training data set; based on an NEP machine learning framework, utilizing the training data set to train and generate a potential function; optimizing the generation process of the potential function by adopting an active learning strategy; and performing thermal conductivity prediction verification on the potential function, and obtaining a thermal conductivity prediction result of the montmorillonite based on the potential function passing the verification. The defect that a traditional classical potential function depends on an empirical or semi-empirical model and is limited in precision and applicability is overcome, the problem that the dynamic behavior and the heat conduction mechanism of a complex material are difficult to accurately capture is solved, the calculation cost is reduced, and meanwhile the precision is kept.

The invention provides a mussel bionic well wall thermal insulation material for drilling fluid as well as a preparation method and application of the mussel bionic well wall thermal insulation material. The mussel bionic well wall thermal insulation material for the drilling fluid is prepared from a viscous polymer, a structure reinforcing material, a nano thermal insulation hollow sphere material and a coating material, and has the characteristics of low heat conductivity coefficient, high strength, slow release of viscosity and high adhesion strength; when the thermal insulation material reaches a high-temperature stratum, the outermost coating layer is gradually broken under the action of high-temperature and high-speed shearing force, the inner viscous polymer-structure reinforcing material-nanometer thermal insulation hollow sphere material composite material is slowly released, the viscous polymer and well wall rock are combined through chemical bonds, and the thermal insulation performance of the well wall is improved. The composite material is tightly adsorbed on the well wall to form a stable heat insulation barrier, the problem that a traditional material falls off due to insufficient adsorption force is solved, and the heat insulation effect in the high-temperature environment is remarkably improved.

The utility model relates to the technical field of mobile phone heat dissipation films, in particular to a high-heat-conduction mobile phone middle frame graphite heat dissipation film which comprises a heat dissipation film body, the heat dissipation film body sequentially comprises matte black single-faced adhesive tape, a high-heat-conduction graphite layer and double-faced adhesive tape from top to bottom, the high-heat-conduction graphite layer is formed by stacking low-temperature carbonization layers and is 0.2 mm in thickness, and the high-heat-conduction graphite layer is formed by stacking low-temperature carbonization layers. The low-temperature carbonization layer is formed by graphene through low-temperature carbonization treatment, the heat conductivity coefficient reaches 2000-2100 W / M.K, energy consumption is reduced through low-temperature treatment, the production cost is indirectly reduced due to the low temperature requirement, the graphene is subjected to low-temperature carbonization treatment, the lattice defect density is reduced, and the stability of the heat conductivity coefficient is ensured; and meanwhile, the 0.2 mm high-thermal-conductivity graphite layer is formed by stacking the low-temperature carbonization layers, so that the occupied space of the heat dissipation film body in the middle frame is reduced.

The invention discloses a copper-molybdenum alloy component and a manufacturing method thereof, and belongs to the technical field of alloy manufacturing. Mo powder is sequentially subjected to vacuum drying treatment, oxidation-reduction treatment and coating treatment, so that the Mo powder has good flowability and powder laying uniformity; under the preset 3D printing condition, the porous Mo framework which is stably formed and complex in structure can be obtained, the problems that an existing rolling composite method is complex in technological process, strict in technological requirement and the like are solved, and the method is suitable for manufacturing parts with small sizes or complex shapes; the porous Mo framework is subjected to vacuum thermocuring and Cu infiltration treatment, and the obtained copper-molybdenum alloy component is excellent in compactness, high-temperature stability, interface bonding strength, heat conduction, electrical conductivity and the like. The problems that a copper-molybdenum alloy obtained in the prior art is poor in wettability and low in density and uniformity, and the mass content of copper is lower than 30%, so that the heat conductivity, the electric conductivity, the air tightness and other performance are low are solved.

The invention discloses a silicon nitride ceramic thermal conductivity prediction method based on machine learning coding-free feature processing. The method comprises the following steps: acquiring a data set; declaring a chemical character string field of the sintering aid as a disordered data type, and preprocessing other numerical characteristics at the same time; keeping the field of the sintering aid as a disordered data type, and preprocessing other numerical values; selecting a gradient lifting decision tree model supporting native processing category features as a prediction model and performing optimization; a to-be-predicted formula-process parameter combination is input into the optimized prediction model, a thermal conductivity prediction value is output in real time, and the to-be-predicted formula-process parameter combination is directly input into the model through an original chemical formula character string. The invention further discloses a device for implementing the method, computer equipment and a readable storage medium. According to the invention, the original chemical formula of the sintering aid can be directly utilized, and the thermal conductivity can be predicted within millisecond response time without any code conversion.

The invention relates to the technical field of aluminum alloy materials, and provides a high-thermal-conductivity 6xxx aluminum alloy, a preparation method thereof and an electronic product structural part. Wherein the 6xxx aluminum alloy comprises the following components in percentage by mass: 0.3 to 0.5 percent of Mg, 0.2 to 0.35 percent of Si, 0.08 to 0.12 percent of Ce, less than or equal to 0.10 percent of Cu, less than or equal to 0.15 percent of Fe, less than or equal to 0.05 percent of Mn, less than or equal to 0.10 percent of Zn, less than or equal to 0.05 percent of Ti, less than or equal to 0.15 percent of total impurities and the balance of Al; and Mg / Si is in the range of 1.3 to 1.5. According to the 6xxx aluminum alloy and the preparation method thereof, the content and the mass ratio of Si and Mn are accurately regulated and controlled, meanwhile, a trace Ce element is added, the thermal conductivity and the anodic oxidation performance of the 6xxx aluminum alloy are improved, solid solution and aging processes are further matched, the beta ''phase and the grain size are controlled, and the alloy has the excellent anodic oxidation performance while having the high thermal conductivity.

The invention relates to the technical field of cable processing, and discloses a mica tape cross-linked polyethylene insulated cable which comprises a copper conductor, a mica tape, a cross-linked polyethylene insulating layer, a filling material, a wrapping layer and a cable sheath from inside to outside, the mica tape comprises mica paper, a reinforcing material and an adhesive, and the adhesive comprises tung maleic anhydride type mica glue and MgO / gamma-Al2O3 composite filler. The adhesive adopted by the mica tape comprises the MgO / gamma-Al2O3 composite filler and the tung maleic anhydride type mica glue, and the MgO / gamma-Al2O3 composite filler can improve the heat conductivity coefficient and the dielectric property of the tung maleic anhydride type mica glue, so that the heat conductivity and the insulativity of the mica tape are improved.

The invention belongs to the technical field of aluminum alloy materials and preparation thereof, and relates to a high-strength and high-toughness die-casting aluminum alloy and a preparation technology and application thereof.The aluminum alloy comprises Si, Mg, Cu, Mn, Zn, Fe, Cr, Ti, Zr, Sr, Sb, B, La, Ce, Be, P, smaller than or equal to 0.05% of other single elements, smaller than or equal to 0.15% of other impurity elements in total and the balance Al element, the content of Sr and the content of Sb cannot be larger than or equal to 0.005% at the same time, and the balance Al element. According to a singly-cast sample prepared from the high-toughness die-casting aluminum alloy, the tensile strength at the room temperature is 380-450 MPa, the yield strength is 250-350 MPa, the ductility is 3-8%, the brinell hardness is larger than or equal to 105 HB, the electric conductivity is larger than or equal to 19 MS / m, and the heat conductivity is larger than or equal to 140 W / m.K; and at the temperature of 200 DEG C, the tensile strength ranges from 280 MPa to 350 MPa, the yield strength ranges from 220 MPa to 290 MPa, and the ductility ranges from 5% to 10%.

The present invention relates to a method for controlling physical properties of a silicon nitride substrate, and more specifically, the method comprises the steps of: producing a silicon nitride substrate; and adjusting a residual magnesium content in the silicon nitride substrate. The thermal conductivity of the silicon nitride substrate is inversely proportional to the residual magnesium content in the silicon nitride substrate, and the flexural strength of the silicon nitride substrate is proportional to the residual magnesium content in the silicon nitride substrate.

The invention discloses a high-heat-conductivity leakproof liquid metal phase change heat-conducting gasket and a preparation method thereof, and relates to the technical field of heat-conducting gaskets. The preparation method comprises the following steps: alloying high-heat-conductivity low-melting-point liquid metal gallium with high-heat-conductivity metal silver and copper, mixing with a polymer containing a specific functional group, adding a modified heat-conducting filler, and carrying out UV curing to form the heat-conducting gasket. Liquid metal is easily alloyed to form eutectic alloy, the melting point can be increased, a chemical cross-linked network formed by the modified heat conduction filler and UV curing can make up heat conduction loss, a heat conduction path is established, the interface thermal resistance is reduced, and the heat conduction efficiency is remarkably improved. The surface oxide layer interacts with the polar group of the polymer, and the steric hindrance effect of the cross-linked network is combined to synergistically realize the leak-proof effect. The high-heat-conductivity leakproof liquid metal phase change heat-conducting gasket prepared by the invention has the effects of high heat conductivity and leakproof.

The invention discloses a high-temperature-resistant and corrosion-resistant coating for an aluminum alloy heat exchange tube and a preparation method thereof, and relates to the technical field of coating materials. The method comprises the following steps that the aluminum alloy heat exchange tube is cleaned and deoiled, then a treating agent is sprayed, composite coating slurry is sprayed to the surface of the aluminum alloy heat exchange tube after curing, and the high-temperature-resistant and corrosion-resistant coating for the aluminum alloy heat exchange tube is obtained after curing treatment. Wherein the treating agent is prepared from NS-30 silica sol, deionized water and methyltrimethoxysilane; the composite coating slurry is prepared from a polyamide acid solution, a synergist, functionalized boron nitride nanosheets, modified hexagonal boron nitride, a flatting agent and a defoaming agent. The silane film introduced into the treating agent and the synergist, the functionalized boron nitride nanosheet and the modified hexagonal boron nitride introduced into the composite coating slurry effectively improve the high temperature resistance, the corrosion resistance, the adhesive force, the thermal conductivity, the aging resistance and the toughness of the coating. Therefore, the method has a wider application prospect.

An acoustic wave device includes a support, a piezoelectric layer, an IDT electrode including first and second busbars and first and second electrode fingers, and a dielectric film provided on the piezoelectric layer so as to overlap at least a portion of the IDT electrode in plan view. When a thickness of the piezoelectric layer is d and a center-to-center distance between centers of adjacent ones of the electrode fingers is p, d / p is less than or equal to about 0.5. A cavity that opens on a side of the piezoelectric layer is provided in the support. The IDT electrode includes an intersection region, and first and second gap regions. The dielectric film is provided at at least a portion of the first and second gap regions, and a thermal conductivity of the dielectric film is higher than a thermal conductivity of the piezoelectric layer.

The invention provides a preparation method of a plate-shaped glassy carbon electrode, which comprises the following steps: curing a resin raw material into a plate-shaped resin block, carbonizing in an inert atmosphere, and respectively introducing a nitrogen source and a boron source for doping operation to obtain a co-doped plate-shaped resin block precursor; placing the co-doped plate-shaped resin block between two porous graphite plates, and carrying out high-temperature treatment to obtain a glassy carbon matrix; and immersing the glassy carbon substrate into the adhesion layer solution to form an adhesion layer, transferring the adhesion layer into a deposition solution which comprises a bismuth-containing solution and a gold-containing solution, forming bismuth-gold nano-dots on the adhesion layer, and washing and drying the bismuth-gold nano-dots to obtain the plate-shaped glassy carbon electrode. Through directional arrangement of crystal orientations, the tantalum carbide coating achieves higher electrical conductivity and thermal conductivity. And the sensitivity and the service life of the plate-shaped glassy carbon electrode are obviously improved and prolonged.

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 relates to the field of furnace lining materials, in particular to a rapid repairing material for a tapping hole and a furnace lining of an intermediate frequency furnace. The rapid repairing material comprises the following components in parts by weight: 50-70 parts of tabular corundum, 10-20 parts of fused magnesite, 8-15 parts of alumina micro powder, 3-8 parts of nano zirconia, 5-12 parts of silicon carbide, 10-15 parts of silica sol and 2-5 parts of a reinforcing agent. Wherein the reinforcing agent is titanium calcium aluminate coated with chromium nickel boride. The tabular corundum is mainly used as an integral framework; the fused magnesite is matched with the alumina micro powder to form magnesium aluminate spinel with a high melting point; the nano zirconium oxide can fill pores and is excellent in toughness; the silicon carbide has the advantages of high hardness, high thermal conductivity and high melting point; the reinforcing agent is titanium calcium aluminate coated with chromium nickel boride, although the adding amount is small, the high-temperature strength, toughness and thermal shock resistance of the repairing material can be remarkably improved, and especially the long-term corrosion resistance can be remarkably improved.