12752 results about "Thermal conductivity" patented technology

A vacuum insulating panel may include: a first glass substrate; a second glass substrate; a plurality of spacers provided in a gap between at least the first and second substrates, wherein the gap is at a pressure less than atmospheric pressure; a seal provided between at least the first and second substrates, the seal including a first ceramic seal layer and a second ceramic seal layer, wherein the second ceramic seal layer is located between at least the first ceramic seal layer and the first glass substrate; and wherein one or more of: (i) a thermal (TC) conductivity of the first ceramic seal layer is be less than a thermal conductivity of the first glass substrate, and wherein the thermal conductivity of the first glass substrate is less than a thermal conductivity of the second ceramic seal layer, so that the thermal conductivity of the second ceramic seal layer is greater than the thermal conductivity of the first substrate and greater than the thermal conductivity of the first ceramic seal layer; (ii) a thermal conductivity of the second ceramic seal layer is greater than a thermal conductivity of the first ceramic seal layer; and / or (iii) a ratio TDp1 / TDg, where TDp1 represents a thermal diffusivity (TD) of the second ceramic seal layer and TDg represents a thermal diffusivity of the first glass substrate, is at least 1.020 and wherein the thermal diffusivity of the second ceramic seal layer is greater than a thermal diffusivity of the first ceramic seal layer.

The invention relates to the technical field of intelligent operation and maintenance of power equipment, in particular to a cable system full life cycle health management method based on digital twinning, which comprises the following steps: step 1, constructing a cable digital twinning body fusing electric-thermal-mechanical-chemical multi-physical fields; 2, dynamically fusing multi-source monitoring data, and collecting a cable skin continuous temperature sequence, a partial discharge pulse waveform and soil environment parameters; 3, solving a coupling equation of conductivity-thermal conductivity-stress tensor-ion diffusivity through iteration to realize multi-physical field linkage simulation; 4, generating a self-adaptive maintenance decision, inputting the insulation aging factor into an LSTM predictor to output a residual life prediction value, and generating a maintenance work order when the residual life is lower than a threshold value; and 5, carrying out closed-loop correction on the model, and updating the insulation aging factor calculation model and the physical attributes of the three-dimensional grid according to actual maintenance data. The method improves the safety, reliability and operation and maintenance efficiency of the cable system, and has important industrial application prospects.

The invention discloses a digital intelligent management method and system for hydraulic engineering construction, particularly relates to the technical field of hydraulic engineering construction management, and is used for solving the problems of regulation lag and insufficient environmental disturbance adaptability of an existing method under the action of multi-physics field coupling. According to the method, a concrete three-dimensional temperature field model is established, initial regulation and control parameters are generated, and a heat conductivity coefficient under the seepage influence is corrected based on space-time relevance of pore water pressure and temperature data; the constraint boundary is dynamically adjusted in combination with the construction progress and the material strength curve, a cooling water pipe coordinated regulation and control matrix is constructed, and target flow instructions of space differentiation are generated through the included angle between the distance and the water flow direction; setting a lag time threshold and optimizing an execution time sequence according to the thermal inertia parameter, splitting the threshold and allocating a weight coefficient when the environmental wind speed suddenly changes, and finally updating the model parameter and the regulation and control instruction; accurate temperature control response and abnormal heat conduction suppression under multi-field coupling are achieved, and the structural safety and construction efficiency under complex working conditions are improved.

The invention discloses a geothermal field parameter inversion calculation method, device and system, and a storage medium. The method comprises the following steps: establishing a geophysical stratified model; through Monte Carlo sampling of preset parameter spaces of the crustal heat generation rate and the heat conductivity, a temperature value is calculated in combination with a heat conduction equation, and a Gaussian likelihood function evaluation model is constructed to predict the matching degree of the temperature and the actually measured temperature; obtaining the optimal estimation of the thermal parameters, a confidence interval and a correlation matrix among the parameters based on the posterior probability distribution; and according to the correlation matrix, taking a high-confidence result generated by Monte Carlo inversion as priori knowledge of a physical guidance neural network PINNs, and finally outputting a thermal parameter spatial distribution prediction result of the target area through parameter initialization constraint, output layer range limitation and a physical regularization loss item. By adopting the technical scheme of the invention, the defects that the existing actually measured geothermal field parameters are rare and the regional characteristics cannot be described and the geophysical joint inversion of the geothermal field parameters cannot be realized in the prior art are overcome.

The invention relates to the technical field of laser material processing, and discloses a laser annealing temperature control method and device.The method comprises the steps that the specific heat capacity, the heat conductivity coefficient, the heat diffusivity, the heat radiation rate, the heat reflectivity and the heat loss coefficient are obtained, and a material thermal characteristic model is established; performing grid division according to the material thermal characteristic model to obtain a laser energy density parameter; extracting a thermal strain coefficient according to the laser energy density parameter, and establishing a temperature-thermal strain mapping relation prediction model; dynamically adjusting a laser power proportion and a pulse width time sequence according to the temperature-thermal strain mapping relation prediction model to obtain temperature field distribution data; according to the temperature field distribution data, carrying out shortest path analysis to obtain a temperature regulation and control decision; and according to the temperature regulation and control decision, inputting a preset control regulation model, and combining reinforcement learning iteration optimization parameters to obtain a temperature control scheme. According to the method, large-range temperature crossing and fine adjustment in an extremely short time can be realized.

A component (202) is disclosed that includes a body (206) and an additive manufactured (AM) metal mass (200) that includes a first section (292) and a stress relief section (294). The stress relief section (294) includes a porous region (300) having a porosity in which an open spatial volume accounts for 2% to 50% of the total volume of the stress relief section (294). The stress relief section (294) has a smaller at least one of thermal conductivity, tensile strength, ductility, and fatigue strength than the first section (292). A braze material (310) couples the AM metal specimen block (200) to a specimen block opening (204) in the body (206). The stress relief section (294) creates a low stress zone in the metal specimen block (200), which can be located near or adjacent to a high stress zone. The stress relief section (294) reduces residual stress in the metal sample block (200), which reduces related challenges to couple the metal sample block (200) to the body (206) of the component (202), particularly in the case of the use of superalloy materials.

The invention discloses spherical aluminum oxide and a silicone rubber heat conduction composite material thereof, and belongs to the technical field of functional polymer materials. The spherical aluminum oxide is subjected to surface modification through an amphiphilic fluorosilicone heat conduction interface synergist; comprising the following raw materials in parts by weight: 100-200 parts of vinyl silicone oil, 1-6 parts of side hydrogen-containing silicone oil, 1-6 parts of end hydrogen-containing silicone oil, 0.2-2 parts of a platinum catalyst, 0.01-0.1 part of an inhibitor and 2500-6000 parts of amphiphilic fluorine-silicon heat-conducting interface synergistic spherical aluminum oxide powder. Through surface modification of spherical aluminum oxide, the prepared silicone rubber heat-conducting composite material realizes synergistic gain of heat conduction, insulation and flexibility, and can meet the requirements of multiple fields such as power battery pack heat dissipation gaskets, high-frequency circuit packaging and wearable equipment.

The invention relates to the technical field of low-dielectric heat-conducting functional materials, in particular to a nano silicone rubber composite material as well as a preparation method and application thereof. According to the preparation method, a modified vinyl silsesquioxane coupling agent is taken as a bridge, and boron nitride nanosheets, silicon carbide nanowires and the modified vinyl silsesquioxane coupling agent are covalently connected through hydrolysis reaction, so that a heterostructure is constructed, and the nano heat-conducting filler is obtained; the preparation method comprises the following steps: dispersing a nano heat-conducting filler in vinyl silicone oil, and constructing a covalent cross-linked network through addition cross-linking reaction and curing treatment to obtain the nano composite silicone rubber material. According to the processing method, the filling amount, the dielectric constant and the dielectric loss can be reduced, meanwhile, the heat conduction capacity is improved, and the problems that in the prior art, the dielectric constant and the dielectric loss are low due to simple mixing of the boron nitride nanosheets and the silicon carbide nanowires are solved.

A component including a body, and an additively manufactured (AM) metal coupon including a first section and a stress-relief section, is disclosed. The stress-relief section includes a porous region having a porosity between 2% to 50% open space volume to total volume of the stress-relief section. The stress-relief section has at least one of thermal conductivity, tensile strength, ductility, or fatigue strength less than first section. A braze material couples the AM metal coupon to a coupon opening in the body. The stress-relief section creates a low-stress zone in the metal coupon that can be located near or adjacent to a high-stress zone. The stress-relief section reduces residual stress in the metal coupon, which reduces the related challenges of coupling the metal coupon to the body of the component, especially where superalloy materials are used.

The invention relates to the technical field of ceramic clay, in particular to wear-resistant ceramic clay and a preparation method thereof.The wear-resistant ceramic clay is prepared from, by weight, 35-40 parts of kieselguhr, 15-20 parts of silicon carbide, 8-12 parts of modifier based on mullite modification, 5-8 parts of modified cordierite agent, 4-7 parts of aluminum oxide, 4-7 parts of calcined talc, 3-5 parts of potassium feldspar and 30-35 parts of water. According to the wear-resistant ceramic clay disclosed by the invention, the diatomite and the silicon carbide are matched with the aluminum oxide, the calcined talc and the potassium feldspar, and the modifier based on mullite modification and the modified cordierite agent are added, so that the wear resistance, the stain resistance and the heat-conducting property of the obtained ceramic clay are coordinated and improved through co-blending and matching of the raw materials and mutual enhancement and improvement of the raw materials; meanwhile, the product is remarkable in anti-damage stability effect.

The invention discloses a cement-based aerogel heat preservation and heat insulation coating material for concrete and a spraying construction process of the cement-based aerogel heat preservation and heat insulation coating material, and belongs to the technical field of concrete materials. The coating material is prepared from powder, composite emulsion and water, and the powder is prepared by mixing superfine sand, cement, modified silicon dioxide-carbon nanotube composite aerogel powder, hollow glass beads, nanofibers, graphene nanosheets, an ultraviolet light absorber, a water reducing agent and a defoaming agent. The composite emulsion is composed of an acrylate copolymer emulsion, a polyvinyl acetate-ethylene emulsion, a temperature-sensitive polymer emulsion and a coalescing agent. Based on the multi-stage pore network and multi-component emulsion optimization design and multi-component synergistic effect, the material has good fluidity after being mixed, and has low heat conductivity coefficient, high strength and high toughness after being hardened; the construction technology of high-pressure water flushing and layered spraying is provided, and the method has the advantages of being efficient in construction, stable in quality and the like and can be applied to heat preservation and heat insulation of a concrete structure in a severe environment.

The invention relates to the technical field of workpiece airtightness detection, in particular to a workpiece airtightness detection method and system based on multi-source data fusion, and the method comprises the steps: collecting the pressure fluctuation, temperature field distribution and vibration spectrum data of a workpiece through a sensor array, and executing a stepped pressure excitation process; the method comprises the following steps: dynamically configuring an inflation rate according to the heat-conducting property of a material, reversely compensating pressure based on temperature field data in a pressure maintaining stage to eliminate thermal deformation interference, and extracting a pressure attenuation rate and nonlinear characteristics, an area proportion of an abnormal low-temperature region and space aggregation of an energy abrupt change point in a vibration spectrum from compensated data; according to the method, multi-physical field features are fused, the detection precision and reliability are improved, and the method is suitable for the airtightness detection requirement in the high-precision manufacturing field.

The invention discloses a reaction-sintered silicon carbide setter plate and a preparation method thereof. The reaction-sintered silicon carbide setter plate product is obtained through powder granulation, compaction and reaction sintering. Wherein the silicon carbide powder of the four particle size sections is matched, the particle size sections are uniform, stacking is more reasonable, coarse particles form a frame, fine particles are filled among the coarse particles, the powder structure is compact in property, and the compactness of a green body obtained after blank pressing is guaranteed; and spray granulation is performed after ball milling, so that all the raw materials and auxiliary materials are uniformly mixed. The surface of the green body pressed by a set oil pressure mold is also provided with a concave-convex structure, so that the contact area between the load bearing plate and the bottom of the domestic porcelain is reduced, air circulation between the load bearing plate and the bottom of the domestic porcelain is increased, and adhesion is effectively avoided. The product has the advantages of long service life, high strength and fast heat conduction, solves the problems of low strength, low heat conductivity and short service life of mullite, and also solves the industrial pain point of adhesion of a reaction-sintered silicon carbide setter plate.

The invention discloses a method for preparing a copper-chromium-niobium alloy high-thermal-conductivity part based on green laser SLM, and relates to the technical field of copper-chromium-niobium alloys. Comprising the following steps that copper-chromium-niobium alloy powder is pretreated; the pretreated copper-chromium-niobium alloy powder is laid on a base plate, green laser is adopted for selective laser melting printing, at least two layers of printing parameters with different energy densities are set in a layered energy gradient control mode, layered printing is carried out, a pore structure with the porosity in continuous gradient distribution is formed, and a pre-machined part is obtained; wherein the wavelength of the green laser is 500 nm to 550 nm, and the spot diameter of the green laser is 15 [mu] m to 30 [mu] m; and the pre-machined part is subjected to heat treatment, and the high-heat-conduction part is obtained. The copper-chromium-niobium alloy part is prepared through the green laser SLM technology, the layered energy density gradient control technology is adopted, and the problems that in copper-based alloy additive manufacturing, the reflectivity is high, the structure is limited, and the performance is insufficient are systematically solved.

The invention provides a self-adaptive teaching-free welding robot intelligent gas saving monitoring system, which relates to the technical field of industrial robots, and comprises a three-dimensional sensing module used for identifying the workpiece material category through a multispectral sensor integrated with a welding gun of a welding robot, meanwhile, a stereoscopic vision camera and a line structure light scanning camera are used for obtaining three-dimensional point cloud data of the welding seam in real time; the parameter adjusting module is used for calling a heat conductivity coefficient database based on the three-dimensional point cloud data, and correcting the initial flow of the welding current, the arc voltage and the protective gas in real time; and the matching control module is used for calculating the arc length variable quantity based on the arc voltage, controlling the opening degree of the gas flow valve through a dynamic regulator, realizing dynamic matching of the gas flow and the changed arc length, and generating gas dynamic matching control parameters. Through cooperative operation of self-adaptive attitude compensation and real-time gas consumption monitoring, teaching-free accurate operation in the welding process is achieved, and intelligent control over gas consumption is improved.

An IC stack includes: a plurality of integrated circuit (IC) structure horizontally separate with each other, wherein each IC structure comprises a top surface, a bottom surface opposite to the top surface, and four sidewalls with a first sidewall, a second sidewall, a third sidewall and a fourth sidewall; wherein the area of the bottom surface or the top surface is larger than that of any sidewall; a laterally extending RDL structure covering each first sidewall of the plurality of IC structures; and an upward extending thermal conductivity layer between two adjacent IC structures. The thermal conductivity of the upward extending thermal conductivity layer is higher than that of Si.

The invention relates to the field of intelligent temperature control of industrial kilns, and discloses a graphitization furnace temperature uniformity optimization processing system which comprises a temperature monitoring module, a dynamic matrix control module, a material-control coupling module, a lattice feedback module and a multi-objective optimization module. The method comprises the following steps: constructing an equivalent temperature field through multi-source temperature data fusion; predicting a graphitization trend and generating a dynamic matrix control instruction in combination with a multi-physical field model; dynamically adjusting a thermal conductivity matching temperature gradient of the guard plate; online correcting a material constant based on lattice feedback; closed-loop control is formed, and the process stability and energy efficiency of the graphitization furnace are improved. Through multi-source fusion monitoring, multi-physical field coupling modeling, dynamic thermal conductivity regulation and control, lattice feedback online correction and reinforcement learning multi-objective optimization, temperature uniformity control and energy efficiency improvement of the graphitization furnace are realized, and material performance and process economy are guaranteed.

The invention discloses a polylactic acid injection molding mold based on a gradient heat conduction composite structure and a heat management method thereof, and belongs to the technical field of high polymer material molding processing equipment.The polylactic acid injection molding mold comprises a) a surface high heat conduction layer which is made of a copper-based composite material, has the heat conduction coefficient larger than or equal to 400 W / m.K and is used for rapidly and directionally transferring heat to the surface of a mold cavity; and b) an intermediate transition layer composed of a titanium alloy porous structure. High-efficiency production is realized through innovative design and advanced technology. Integrated metallurgical bonding of the gradient heat conduction structure is achieved through the selective laser melting technology, and the heat flow directivity is enhanced; the dual-mode cooling system is combined with closed-loop temperature control, and the temperature is accurately regulated and controlled; the high-performance material improves the comprehensive performance of the mold; and the structural stability is guaranteed through accurate technological parameters. According to the thermal management method, through multi-physical field simulation optimization, rapid heating and cooling are achieved, the forming period is shortened to 16-18 seconds, the calculation efficiency is improved by 80%, and the production efficiency and the product quality are effectively improved.

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 preparation method of a high-heat-conductivity and high-density normal-temperature hydrogen storage material block, and relates to the field of hydrogen storage materials, and the preparation method comprises the following steps: step 1, uniformly mixing normal-temperature hydrogen storage material powder, binder powder and carbon material powder according to a set mass ratio to form mixture powder; 2, putting the mixture powder into a tablet press mold, and pressing the mixture powder into blocks; step 3, carrying out heat treatment on the block body under a vacuum or inert atmosphere condition; and 4, after heat treatment is completed, cooling the material to a set temperature, and taking out the material to obtain the high-heat-conductivity and high-density normal-temperature hydrogen storage material block. Through a pressing-cladding method, the binder and the normal-temperature hydrogen storage alloy powder are mixed, pressed and formed, so that the binder and the alloy particles are in close contact or are embedded, the binder is melted through heating, the alloy particles are coated with the melted binder, the alloy particles are adhered, the contact thermal resistance of the alloy particles is reduced, and the hydrogen storage capacity of the hydrogen storage alloy is improved. And the thermal conductivity of the material is greatly improved.

The invention relates to the technical field of ceramic materials, in particular to a ceramic composite material and a preparation method thereof.The ceramic composite material is prepared from, by weight, 30-35 parts of silicon carbide, 15-20 parts of boron nitride, 10-15 parts of silicon dioxide, 8-11 parts of additive based on modified filler and 7-10 parts of ball milling agent based on sodium alginate reconditioning modification. According to the ceramic composite material, silicon carbide and boron nitride are matched with silicon dioxide, the additive based on the modified filler and the ball-milling agent based on sodium alginate reconditioning modification are blended and coordinated, and through coordination and synergism of the raw materials, the obtained product can achieve coordinated improvement of strength, wear resistance and thermal conductivity; and the product has remarkable heat-resistant and corrosion-resistant stability effects.

The invention discloses a preparation method of a textured silicon nitride ceramic substrate, and belongs to the technical field of ceramic products. Beta-silicon nitride whiskers with the long diameter of 4-15 microns and the short diameter of 1-3 microns are added into silicon nitride ceramic slurry according to the design, and when the whiskers containing beta-silicon nitride pass through a scraper of a casting machine, the whiskers tend to be directionally arranged in the casting direction, so that a textured structure is generated in the silicon nitride ceramic substrate. The textured structure is beneficial to improving the three-point bending strength, the fracture toughness and the thermal conductivity in the horizontal direction of the ceramic substrate.

The invention relates to the field of building materials, and discloses a multifunctional foamed ceramic sound insulation and heat preservation material for buildings. Comprising the following raw materials in parts by weight: 42 to 48 parts of pottery clay tailings, 14 to 16 parts of fly ash, 10.5 to 12 parts of crushed stone materials, 2.8 to 3.2 parts of a silicon carbide foaming agent, 0.7 to 0.8 part of a borax fluxing agent, 7 to 8 parts of paraffin / silicon dioxide phase change microcapsules, 0.5 to 1.0 part of graphene, 2.0 to 2.5 parts of nano iron powder, 0.05 to 0.5 part of nano silver, 1.0 to 1.5 parts of photocatalytic titanium dioxide and 0.3 to 0.4 part of a fluorosilane coupling agent. A stable matrix structure is constructed through the argil tailings, the fly ash and the crushed stone materials, the silicon carbide foaming agent and the borax fluxing agent reduce the heat conductivity coefficient, the sound insulation performance is improved, the material is endowed with the antibacterial ability through nano-silver and photocatalytic titanium dioxide, indoor sanitation is guaranteed, and a super-hydrophobic layer is constructed through the fluorosilane coupling agent.

The invention discloses a solid electrolyte membrane and a preparation method and application thereof. The solid electrolyte membrane comprises a first electrolyte close to the positive pole piece and a second electrolyte layer close to the negative pole piece. The first electrolyte layer comprises a polymer, a lithium salt and an additive, and the second electrolyte layer comprises a solid electrolyte, a polymer, a lithium salt and an additive. The first electrolyte layer has a wide electrochemical window and relatively high mechanical properties, and can be matched with a high-voltage positive electrode material and improve solid-solid interface contact. The solid electrolyte of the second electrolyte layer is mainly composed of a continuous vertical array micro-mesoporous material, has a micro-mesoporous structure and high surface adsorption energy, and can accelerate lithium salt dissociation, reduce molecular interaction between polymer chains, form a three-dimensional continuous fast ion transmission channel and a heat conduction network, and improve ionic conductivity and safety performance. The solid electrolyte membrane disclosed by the invention has excellent ionic conductivity, wide electrochemical window, high safety performance and excellent electrochemical performance.

A millimeter wave radar altimeter structure disclosed by the present invention comprises a shell, the shell is provided with a plurality of functional areas and integrates a plurality of functional units, the functional units comprise a radio frequency unit, an intermediate frequency processing unit and a signal control unit, and the plurality of functional units are compactly arranged in the shell. The radio frequency unit comprises at least one high-power emission chip, the chip is installed on a heat conduction substrate, and the substrate is in contact with the shell to form a heat conduction path. The shell is made of a high-heat-conductivity material, and a plurality of heat dissipation structures are arranged outside the shell, so that the heat dissipation efficiency under natural convection is improved. The heat conduction substrate, the shell material and the heat dissipation structure form a continuous heat dissipation path from the chip to the environment, heat accumulation is effectively restrained, and stable work of the chip is guaranteed. The shell further comprises a sealing structure, a sealed space is formed by a sealing groove, a sealing element, the antenna cover and the packaging cover plate, and environment sealing protection is achieved. The signal control unit is connected with peripheral equipment through an external interface, and the interface supports power supply and data communication of the altimeter.

The invention discloses a graphene fiber and resin composite material with high thermal conductivity. The graphene fiber and resin composite material comprises continuous graphene fiber filaments, wherein the surfaces of the continuous graphene fiber filaments are coated with a sizing agent; the surface of the graphene fiber is coated with the modified epoxy resin; the preparation method comprises the following steps: preparing continuous and uniform graphene oxide fiber filaments through a wet spinning technology; fully reducing the graphene oxide fiber through a chemical reduction method; performing graphitization treatment on the graphene oxide fiber subjected to chemical reduction at ultrahigh temperature to obtain graphene fiber; then the graphene fiber laying layer is put into a mold coated with demolding wax, each layer of fiber is fixed with epoxy resin, and demolding cloth covers the graphene fiber laying layer after the graphene fiber laying layer is finished and is used for demolding and absorbing redundant resin; the graphene fiber / resin composite material prepared by the preparation method disclosed by the invention not only has good heat-conducting property, but also has relatively good interface property.

According to the intelligent radiator welding method and system based on welding residual stress control, temperature field data of a welding area are obtained through a sensor array, a temperature gradient mapping image is generated, residual stress distribution is determined through heat-structure coupling finite element analysis, and a thermal expansion coefficient and a welding speed parameter are extracted; when the deviation exceeds a deviation threshold value, the heat input power and the welding speed are adjusted, parameter combination is optimized, heat input distribution is redistributed, new temperature field distribution is generated by adopting a power segmentation adjustment algorithm, residual stress relief data are extracted, and if the stress reduction rate is insufficient, the welding speed is adjusted; if yes, cooling parameters are adjusted for thermal stress release, through finite element iteration fed back in real time, a process correction scheme is generated, full-process simulation verification is conducted, and the fatigue life and the thermal conductivity index are obtained. Accurate control over the residual stress in the welding process is achieved, and the intelligent welding quality and the structural stability are improved.

The invention relates to the technical field of crystal material preparation, in particular to a ternary layered selenide Ge3Sb4Se7 semiconductor material and a preparation method thereof. The preparation method of the ternary layered selenide Ge3Sb4Se7 semiconductor material comprises the following steps that S001, germanium powder, antimony powder and selenium powder with the molar ratio being 3: 4: 7 serve as raw materials, the temperature is increased to 900-950 DEG C under the vacuum condition, and heat preservation is conducted for 12-24 h at the temperature; s002, after heat preservation is finished, the temperature is reduced to 475-500 DEG C at the cooling rate of 1-5 DEG C / min, and heat preservation is conducted for 3-5 days at the temperature; and after heat preservation is finished, furnace cooling or quenching cooling is performed to reach the room temperature, and the layered ternary selenide single-phase material with the chemical formula being Ge3Sb4Se7 is obtained. The ternary layered selenide Ge3Sb4Se7 semiconductor material prepared by the invention is a single-phase material and has the characteristics of low thermal conductivity and low resistivity, so that the ternary layered selenide Ge3Sb4Se7 semiconductor material has application potential in the fields of thermoelectric devices, photoelectric detection and the like.

The invention discloses a thermal insulation performance detection method and system for a composite wallboard, and relates to the technical field of building material detection, and the method comprises the steps: dividing a composite wallboard sample into a plurality of grids, setting an inversion starting point for each grid according to initial data, starting an inversion algorithm to gradually adjust the heat conductivity coefficient of each grid, and generating a heat conductivity coefficient distribution diagram, calculating the average heat conductivity coefficient and the overall thermal resistance value of the sample; the test platform applies full-automatic thermal excitation and sound wave excitation to a sample, collects sound signals and thermal imaging data related to internal defects of the composite wallboard, calculates the optimal matching time point of the sound signals and the thermal imaging data, and extracts defect related characteristics in the sound signals and temperature anomaly characteristics in thermal imaging in a double-flow processing mode. Generating a comprehensive defect distribution diagram, and comparing the comprehensive defect distribution diagram with the heat conductivity coefficient distribution diagram and the average heat conductivity coefficient to obtain preliminary judgment; through acoustic-thermal multi-mode cooperative detection, the spatial distribution of tiny defects in a sample is accurately positioned, and the influence of the tiny defects on the heat-conducting property is judged.

The invention relates to the technical field of heat-conducting graphite materials, in particular to a POD precursor film, a POD-based graphite film and a preparation method of the POD precursor film, the POD-based graphite film and the preparation method of the POD precursor film. After the reaction is finished, obtaining an antioxidant modified aromatic polyoxadiazole polymer solution; the preparation method comprises the following steps: coating an antioxidant modified aromatic polyoxadiazole polymer solution with a wiped film, then carrying out solidification forming in a multi-stage coagulation bath, and finally neutralizing, washing and drying to obtain a POD precursor film; the coagulating bath is an aqueous solution of sulfuric acid and boron compounds and an aqueous solution of sulfuric acid. And carrying out carbonization treatment and graphitization treatment on the POD precursor film to obtain the POD-based graphite film. According to the preparation method, the boron element is cooperatively introduced into and out of the POD precursor film, so that the oxidation resistance of the graphite film is remarkably improved while the high thermal conductivity is maintained.