1637 results about "Heat resistance" patented technology

The invention discloses a high-temperature-resistant, high-voltage-resistant and anti-breakdown capacitor base film and a preparation method thereof. The high-temperature-resistant, high-voltage-resistant and anti-breakdown capacitor base film is prepared from the following raw materials in parts by weight: 100 parts of polypropylene; 17 to 36 parts of polyvinylidene fluoride; 3-12 parts of enhanced and improved talcum powder; 1-6.5 parts of modified barium titanate; 1-6 parts of a cross-linking agent; 2-10 parts of a compatilizer; and 0.05-2 parts of an initiator. The capacitor base film is high in mechanical strength, and has excellent high temperature resistance, thermo-oxidative aging resistance, high voltage resistance and anti-breakdown performance; the enhanced and improved talcum powder is constructed by taking expanded layer modified talc as a carrier and titanium dioxide-carbon dot composite particles as a loading component and grafting and coating the organic matter, so that the defects of the talcum powder can be overcome, and the improvement effect of the talcum powder on heat resistance, high-voltage resistance and breakdown resistance can be fully exerted; meanwhile, the system can be endowed with excellent thermo-oxidative aging resistance.

The invention provides an aluminum alloy material, a preparation method thereof and a cable. The aluminum alloy material is prepared from the following components in percentage by mass: 0.03 percent to 0.06 percent of Si, 0.80 percent to 1.2 percent of Fe, 0.15 percent to 0.25 percent of Cu, 0.005 percent to 0.03 percent of B, 0.001 percent to 0.02 percent of Ti, 0.05 percent to 0.15 percent of Y, 0.08 percent to 0.2 percent of the total mass of La and Ce and the balance of Al. The specific content of Fe is added into the aluminum alloy material and cooperates with the rare earth elements Y, La and Ce, and the elongation at break of the aluminum alloy material is improved; meanwhile, due to the addition amount of the Y element, the fatigue resistance of the material is further improved, the toughness of the material is improved, and the heat resistance and cold resistance of the material can be improved. A specific content of boron element is added to form nuclear particles, so that the effect of refining grains is achieved, and the tensile strength of the aluminum alloy material is improved; and meanwhile, the resistivity of the aluminum alloy material is further reduced through cooperation of the boron element and other components. And the titanium element can also play a role in refining grains, so that the tensile strength of the material is further improved. The cable prepared from the aluminum alloy material can meet the requirement of a cable torsion experiment.

The invention belongs to the technical field of heat-conducting materials, and provides liquid metal-based composite heat-conducting silicone grease as well as a preparation method and application thereof. The modified silicone oil, the liquid metal, the heat-conducting auxiliary filler and the hydrophobic fumed silica in a specific ratio are used as main components of the liquid metal-based composite heat-conducting silicone grease, and the liquid metal-based composite heat-conducting silicone grease prepared by the invention has high heat conductivity coefficient (up to 6.05-10.0 W / mk) and low heat resistance (as low as 0.01-0.03 DEG C * cm < 2 > / W), can maintain a good appearance in double-85, high temperature 125 DEG C and temperature cycle aging tests, and has a wide application prospect. Therefore, the structure is suitable for an assembly interface of a power module and a radiator with high-power heat dissipation requirements, and the heat dissipation efficiency is improved.

The present application relates to the technical field of polyimides and relates to a preparation method for a high-performance polyimide and an application thereof, aiming to solve the problems in the prior art such as numerous side reactions and severe impact on transparency caused by an excessively high imidization reaction temperature during the use of a high-temperature thermal imidization method for the preparation of polyimides. The preparation method comprises: (1) preparing a polyamic acid solution; (2) adding a chemical catalyst and a polyamic acid solution to partially complete an imidization reaction; (3) adding an end group auxiliary agent, performing coating with the solution, heating, and maintaining the heat to complete the imidization reaction; and (4) carrying out high-temperature treatment to obtain a high-performance polyimide. The present application can significantly reduce numerous side reactions present in a traditional imidization reaction, eliminate an adverse effect of high-temperature imidization on the optical performance, greatly improve the mechanical properties, heat resistance, optical performance, etc. of a material, and also achieve both high heat resistance and high transparency.

The invention relates to the technical field of aluminum alloy wire processing, and particularly discloses a high-modulus high-conductivity heat-resistant aluminum alloy material, an aluminum wire, a preparation method and a power transmission cable. According to the high-modulus, high-conductivity and heat-resistant aluminum alloy material provided by the invention, the nanoscale TiB2 particles and the micron-sized SiC particles are compounded in the aluminum alloy powder, a dual-reinforcement system is constructed, and the mechanical property and the electrical property of an aluminum conductor are synergistically improved. The invention further provides a preparation method of the high-modulus and high-conductivity heat-resistant aluminum conductor. According to the process, a multi-stage coupling plastic processing technology of hot extrusion, continuous rolling, drawing and surface treatment is adopted. The grain structure is refined through the dynamic recrystallization effect in the series of machining processes, oxidation film defects on the surface and in the structure are damaged through plastic deformation, the rigidity and the conductivity of the aluminum wire are further optimized, and the technical bottleneck that high modulus, high conductivity and heat resistance of traditional aluminum alloy are difficult to consider at the same time is effectively solved.

The invention belongs to the technical field of material processing, and discloses a magnesium alloy casting semi-solid injection molding method and application, and the method comprises the following steps: checking and adjusting a semi-solid injection machine, a casting mold and other equipment to be in a normal state, and placing magnesium alloy particles in a designated area of a hopper; putting a long nozzle of the semi-solid injection platform into the center of a mold sprue; setting the temperature of each section of a mold temperature controller, a charging barrel and a nozzle; preserving heat for a period of time after the temperature of the charging barrel reaches a set value, so that the temperature of materials in the charging barrel is uniform; setting the injection rate, the cooling time, the material return distance and the melt pressure of the semi-solid injection machine; and after a release agent is quantitatively sprayed to the mold, a semi-solid injection program is started, and a casting is obtained. The AS41B magnesium alloy particles with good heat resistance are adopted as the raw material, the semi-solid injection molding method is combined, a melting furnace is not needed, only heating to the semi-solid state is needed, the melt temperature is low, energy is saved, the service life of a mold is prolonged, protective gas is not needed, and the manufactured casting is good in mechanical property and high in heat resistance.

The present invention relates to an intrinsically high thermal conductivity-low dielectric polyimide film, its preparation method, and applications. The polyimide is composed of polyimide A and polyimide B through blending or grafting. The polyimide film of the present invention has intrinsically high thermal conductivity, low dielectric constant and loss, and excellent heat resistance and mechanical properties. It has broad application prospects in integrated circuits, electronic packaging, and other fields.

The invention relates to the technical field of electrolytic copper foil processing, printed circuit board processing and electrolytic copper foil, in particular to a preparation method of a bi-component stripping layer carrier copper foil and the bi-component stripping layer carrier copper foil. The preparation method provided by the invention comprises the following steps: preparing a carrier copper layer; preparing a first inorganic stripping layer on the smooth surface of the carrier copper layer through an electrochemical / physical vapor deposition method; preparing a second inorganic stripping layer on the surface of the first inorganic stripping layer through a low-temperature chemical vapor deposition method; preparing an ultra-thin copper layer on the surface of the second inorganic stripping layer through a pulse electrochemical deposition method; carrying out roughening treatment on the ultra-thin copper layer; and constructing a non-copper functional layer on the surface of the roughened ultra-thin copper layer, and carrying out silane coupling agent coating treatment to obtain the double-component stripping layer carrier copper foil. The two-component inorganic matter is used as the stripping layer of the carrier copper foil, the heat resistance of the stripping layer of the carrier copper foil is improved, and meanwhile the stability of the separating force between the ultra-thin copper layer and the carrier copper layer is improved.

The invention relates to the field of copper-clad plates, and discloses a high-performance flame-retardant low-dielectric-loss copper-clad plate and a preparation method thereof.The copper-clad plate comprises epoxy resin, benzoxazine resin, composite filler, carboxyl-terminated nitrile rubber, an active diluent, a curing agent and the like; the composite filler is prepared by compounding flame-retardant modifier grafted graphene oxide and epoxy silane modified silicon dioxide hollow spheres; according to the flame-retardant modifier, boric acid and pentaerythritol are used for preparing a double-terminal hydroxyl boron-containing intermediate, then dichlorodiphenyl silane and phenylphosphonic dichloride react with hydroxyl groups at the two ends of the intermediate to prepare a flame-retardant intermediate, and amino silane and vanillic aldehyde react with chlorine atoms at the two ends of the intermediate to prepare an aldehyde modified flame-retardant intermediate; the copper-clad plate prepared by the preparation method disclosed by the invention is low in dielectric constant and dielectric loss, high in heat conductivity coefficient and good in flexibility, and also has excellent heat resistance and flame retardance.

The invention discloses an aircraft fairing and a fairing body composite material integrated forming process, and relates to the technical field of aviation equipment manufacturing. The forming process comprises the following steps: 1) preparing a prepreg; (2) sectional forming; 3) a curing process; (4) demolding and trimming; 5) an assembly process; the whole of the front section, the middle section and the tail section of the fairing is of a long-size U-shaped streamline structure. According to the invention, through molecular collaborative design of fluorination modification-polysiloxane toughening-cyanate ester interpenetration, the key contradiction of a high-performance fairing material is systematically solved; ultrahigh strength and toughness are realized at the same time by utilizing in-situ nano microphase separation; a dense graphite carbon layer is generated through catalysis, so that efficient halogen-free flame retardance is achieved; by means of the partition design of molecular fluorination and surface metallization, the high wave transmission and lightning protection functions are ingeniously unified. And finally, a new generation of aircraft fairing composite material with force bearing, wave transmission, heat resistance, impact resistance and environmental stability is successfully prepared.

The invention discloses a gradient gradual change type powder reinforced metal matrix composite material and a preparation method and application thereof, and the gradient gradual change type powder reinforced metal matrix composite material is composed of a metal matrix and gradient gradual change type powder dispersed in the metal matrix. The gradient gradual change type powder sequentially comprises a core carbon material, a transition layer, a gradual change layer and a modification layer from inside to outside, a compound or a solid solution is formed at an interface, so that the binding force and heat resistance of the material are enhanced, the gradient gradual change coating is formed from inside to outside, interface stress is reduced, good metallurgical bonding with a matrix can be achieved, and the service life of the material is prolonged. The service life of the material is prolonged, so that the comprehensive performance of the composite material is remarkably improved.

The invention discloses an AlCrN / TiSiN / AlCrTiSiON pre-oxidation multilayer composite coating and a preparation process thereof, belonging to the technical field of coatings. The bottom layer of the composite coating is an AlCrN transition layer, and an AlCrN / TiSiN nano multilayer film and a TiSiN high-hardness layer are sequentially stacked for 1-4 times on the transition layer; The outermost layer is a compact AlCrTiSiON pre-oxidation coating, wherein the AlCrTiSiON pre-oxidation coating has excellent wear resistance and heat resistance. The coating is prepared by adopting an arc ion plating technology. The invention prepares the pre-oxidation coating with high hardness, high wear resistance and high heat resistance through process design and optimization of coating structure and pre-oxidation layer process parameters.

The invention relates to the technical field of design and processing of PVC (polyvinyl chloride) composite materials, in particular to a multi-layer composite processing method of a PVC decorative film based on heat resistance, which comprises the following steps: firstly, preparing PVC resin powder, various additives and a nano modified additive, premixing and mainly mixing the raw materials, uniformly mixing under the protection of nitrogen, plasticizing and extruding by using a double-screw extruder, and carrying out extrusion molding to obtain the PVC decorative film based on heat resistance. Surface treatment including plasma and chemical etching is carried out after extrusion, then a modified polyurethane bonding layer containing a silane coupling agent is coated and compounded with a micro-nano structure PET decorative film, ultrasonic vibration is applied, then hot-pressing shaping is carried out, a hot-pressing roller is provided with micro textures, finally cooling and rolling are carried out, and all the steps have specific parameters. According to the method, the effect is remarkable, the heat resistance of the PVC decorative film is greatly improved, the heat deformation temperature is increased, the processing performance is optimized, the production efficiency is improved, the bonding and compounding effect is enhanced, the decorative layer is not prone to falling off, the environmental protection property and the product attractiveness are further improved, and the market competitiveness is enhanced.

The invention relates to the technical field of high-molecular polypropylene films, and discloses a PP film for a low-loss capacitor, which is prepared from the following ingredients in parts by mass: 80 to 95 parts of heat-resistant polypropylene resin base materials, 3 to 12 parts of dielectric modifiers, 0.1 to 0.2 part of nucleating agents, 0.05 to 0.8 part of lubricating agents and 1 to 3 parts of stabilizing agents. Through the synergistic effect of specific components, for example, large conjugate structures of the dielectric modifier and the stabilizer synergistically absorb and dissipate electric field energy and the like, the dielectric loss of the PP film is effectively reduced, so that the PP film can reduce heating of a capacitor in a high-frequency or high-voltage application scene, the service life of the capacitor is prolonged, and the safety of the capacitor is improved; and the strict standard of modern electronic equipment on dielectric loss of the capacitor is met. The PP film provided by the invention can maintain the stability of dielectric constant and dielectric loss in a high-temperature working environment, solves the problem of performance reduction caused by insufficient heat resistance of a traditional PP film, and expands the applicability of a capacitor in a high-temperature application scene.

The invention relates to a high-temperature-resistant temperature and vibration composite sensor applied to the field of measurement and testing, which comprises a composite sensor body and a composite circuit board arranged in the composite sensor body, and adopts the cooperation of a thermal insulation sleeve, a magnetic induction ring, a thermal insulation protection feedback unit and a ventilation regulation and control unit. According to the composite sensor, the adaptability of the composite sensor body to the environment is effectively promoted, the composite sensor body can be effectively isolated and protected under the high-temperature condition, and the situation that components in the composite sensor body are damaged due to continuous heat transfer is prevented, so that the durability of the composite sensor body is remarkably improved; meanwhile, heat exchange protection can be effectively carried out on the internal environment of the composite sensor body, the influence of heat on all components in the composite sensor body is further reduced, and the heat resistance of the composite sensor body is enhanced.

A sheath aging resistant cable belongs to the technical field of cables and comprises a conductor assembly and a control wire core assembly, the conductor assembly and the control wire core assembly are sleeved with a sheath unit, the sheath unit comprises an anti-aging additive slow-release structure, and the anti-aging additive slow-release structure comprises an outer slow-release layer, an additive and an inner slow-release layer. The cable is provided with the anti-aging additive slow-release structure, continuously provides protection for the sheath, prolongs the duration of the anti-aging effect, avoids the problem that the conventional protection mode cannot continuously perform the anti-aging effect on the cable sheath in the later period, and is longer in protection time for the cable sheath compared with the conventional mode, and the service life of the cable sheath is prolonged. By arranging the nano sheath, the mechanical property, heat resistance and aging resistance of the sheath material can be enhanced, so that the sheath material can better resist the influence of external stress and environmental factors, mastoid salient points can form a layered structure with a rough surface on the outer wall of the cable, and the effects of soaking corrosion and the like of water in the natural environment on the outer sheath are reduced.

The invention discloses a battery diaphragm as well as a preparation method and application thereof. The battery diaphragm comprises a base membrane and a composite coating formed on at least one side surface of the base membrane, the composite coating comprises a composite inorganic material, and the composite inorganic material comprises a porous layered bimetallic oxide and MOFs particles grown on the surface of the porous layered bimetallic oxide in situ. According to the invention, a composite coating is formed on the surface of the base film by using a composite inorganic material, and the unique pore structure and the layered structure of the porous layered bimetallic oxide LDO provide more liquid storage and retention spaces. The MOFs have good thermal stability, good chemical stability and a unique pore structure, so that the MOFs are endowed with relatively good ion conduction capability, heat resistance and stability. The synthesized MOFs particles grow in situ on the surface of the porous bimetal oxide, so that the bonding force between the particles is improved, and the particles are easier to transfer to the surface of a pole piece after being in contact with the pole piece and hot-pressed, thereby improving the safety of the battery.

The invention discloses an ultrahigh-strength maraging steel wire as well as a preparation method and application thereof, and belongs to the field of steel product manufacturing. The steel wire alloy comprises the following components in percentage by weight: 0.02%-0.05% of C, 0.10%-0.35% of Si, 0.20%-0.60% of Mn, 0.60%-2.50% of Cr, 18.5%-22.0% of Ni, 8.0%-13.0% of Co, 1.2%-2.0% of Ti, 3.0%-5.5% of Mo, 0.10%-0.50% of Al, less than or equal to 1.50% of Cu, less than or equal to 1.50% of Nb, less than or equal to 0.05% of V, less than or equal to 0.04% of N, less than or equal to 0.02% of La + Ce and the balance of Fe and inevitable impurity elements. And the equivalence ratio Nieq / Creq of nickel to chromium is greater than or equal to 1.80. The steel wire provided by the invention has ultrahigh strength, excellent toughness and plasticity, wear resistance, heat resistance, drawing performance and bending and twisting performance.

The invention belongs to the technical field of nylon materials, and particularly relates to a high-heat-resistance halogen-free flame-retardant nylon material and a preparation method thereof. According to the invention, PA6 and PA66 base materials are compounded by utilizing the high heat resistance of PA66 and the processability advantage of PA6, and the heat deformation temperature of the material is improved through the synergistic effect of the modified glass fiber reinforcing agent and the antioxidant, so that the heat-resistant requirements of high-end scenes such as new energy automobile battery components and high-temperature electronic components are met. Halogen flame retardants are completely abandoned, the modified halogen-free flame retardant is adopted, the flame retardant effect is achieved, meanwhile, no harmful halogen hydride gas or dioxin is released during combustion, and the material still keeps excellent rigidity and toughness on the basis of high flame retardance and high heat resistance and is suitable for popularization and application. The problem that the mechanical property of a traditional halogen-free flame retardant is reduced due to high addition amount is solved.

The invention belongs to the technical field of aluminum alloy cables, and discloses a high-strength heat-resistant light-weight green aluminum alloy cable which sequentially comprises a silver-aluminum alloy conductive core, a conductor shielding layer, an insulating layer, an insulating shielding layer, a PP filling rope, a non-woven fabric wrapping tape, a steel belt and a heat-resistant flame-retardant waterproof outer sheath layer from inside to outside. The silver-aluminum alloy conductive core comprises the following components in percentage by weight: 0.01 to 0.3 percent of Cu, 0.3 to 0.8 percent of Fe, 0.03 to 0.1 percent of Si, 0.01 to 0.05 percent of Zn, 0.02 to 0.05 percent of Mg, 0.001 to 0.04 percent of B, 0.01 to 0.08 percent of Ag and the balance of Al; the silver and copper microalloying effect is cooperated with the molded line film drawing process, so that the strength and the conductivity of the conductor are improved; and the outer sheath layer takes a polydimethylmethylhydrosiloxane grafted waterproof agent and a 4-vinyl aniline polymer as functional modifiers, and PVC is compounded, so that the cable is endowed with excellent heat-resistant, flame-retardant and waterproof characteristics.

The composite membrane comprises a base membrane layer and a functional layer, the functional layer comprises at least two material layers which are arranged in a stacked mode, and the at least two material layers are selected from an inorganic ceramic layer, a solid electrolyte layer and a high-temperature-resistant polymer layer. The at least two material layers are arranged on at least one side of the base film layer; wherein the functional layer comprises a high-temperature-resistant polymer layer, and the high-temperature-resistant polymer layer is arranged on the surface of the base film layer; when the functional layer does not comprise the high-temperature-resistant polymer layer, the solid electrolyte layer is arranged on the surface of the base film layer. According to the composite diaphragm, the heat resistance of the diaphragm is improved, and the use safety of the lithium battery is improved.

The invention discloses a polyimide composite material and a preparation method thereof, and relates to the technical field of functional composites.The polyimide composite material is composed of hollow quartz fibers and silicon-containing polyimide resin, the fiber volume content of the polyimide composite material is 45%-60%, and the density of the polyimide composite material is 1.25-1.55 g / cm < 2 >; wherein the silicon-containing polyimide resin is formed by polymerizing a mixture of aromatic dianhydride, aromatic diamine and diamine containing a siloxane structure, and an end-capping reagent. The preparation method comprises the following steps: synthesizing a polyamide acid solution, preparing a prepreg by preimpregnation, performing by a vacuum bag method, performing hot-pressing curing and performing high-temperature post-treatment. Through collaborative innovation of the components and the process, the preparation method is simple, and the composite material has ultralow density, ultrahigh heat resistance, low dielectric constant and high strength and is suitable for the fields of aerospace, 5G communication, semiconductors and the like.

The utility model discloses a capacitor circuit board aging device, which comprises a test frame, the test frame is composed of a plurality of insulation support plates and four support columns, the upper surface of each insulation support plate is uniformly provided with a plurality of placing seats, each insulation support plate is connected with a plurality of wire holders, and the wire holders are connected with a plurality of wiring terminals. And a heating assembly for testing the heat resistance of the capacitor circuit board is arranged on the test frame. The utility model solves the problems that the aging test of the capacitor circuit board is only carried out in a normal room temperature environment at present, but the capacitor circuit board generally installed in electronic equipment is in a high temperature state for a long time, and the aging test in a conventional room temperature environment is not comprehensive enough.

The invention belongs to the technical field of aluminum alloys, and particularly provides a heat-resistant aluminum alloy and a preparation method and application thereof.The heat-resistant aluminum alloy comprises, by mass, 4.3%-4.8% of Cu, 1.3%-1.8% of (Mn + Fe), 0.8%-1.3% of Si, 0.04%-0.1% of Ti and the balance A, and Fe / Mn = 0-0.5 l. According to the chemical components, the alloy plate prepared through a series of processes such as casting, homogenization, hot rolling, cold rolling, solid solution, quenching and aging has good heat resistance and has the advantage of being low in cost due to the fact that the Ni element is not added.

The invention provides a method for calculating the inner wall temperature based on the condensation heat transfer process of a blast furnace gas pipeline. The method for calculating the temperature of the inner wall based on the condensation heat transfer process of the blast furnace gas pipeline comprises the following steps: S1, calculating the thermal resistance of convective heat transfer between the inner wall of the gas pipeline and blast furnace gas; s2, calculating the thermal resistance of heat conduction between the gas pipe walls; s3, thermal resistance of convective heat transfer from the outside of the gas pipeline to the outer wall of the gas pipeline is calculated; and S4, calculating the corrosion temperature of the inner wall surface of the blast furnace gas pipeline according to the total thermal resistance, the blast furnace gas temperature and the environment temperature. According to the method for calculating the inner wall temperature based on the condensation heat transfer process of the blast furnace gas pipeline, the heat resistance of each part of the blast furnace gas in the heat transfer process is calculated on the basis of the heat convection and heat conduction process, and the scientific and systematic method for calculating the inner wall temperature of the blast furnace gas is established; the corrosion condition of the blast furnace gas pipeline can be conveniently predicted, and the safe operation of the blast furnace gas pipeline can be monitored.

The invention relates to the technical field of aluminum alloy wire manufacturing, and particularly discloses a high-strength heat-resistant aluminum alloy wire and a preparation method thereof.The high-strength heat-resistant aluminum alloy wire is composed of, by mass, 0.1%-0.2% of Zr, 0.05%-0.1% of Fe, 0.01%-0.03% of Zn, 0.06%-0.1% of Si, 0.18%-0.25% of doping substances, 0.01%-0.05% of other impurities and the balance Al, the doping substances are composed of W2B and MoB2, and the balance Al is Al. According to the high-strength heat-resistant aluminum alloy wire provided by the invention, through optimal design of zirconium (Zr), iron (Fe), zinc (Zn) and silicon (Si) elements and doped substances W2B and MoB, the heat resistance and tensile strength of the aluminum alloy wire are remarkably improved on the basis of keeping good conductivity of the aluminum alloy wire.

The invention relates to the technical field of cabinet heat dissipation, and discloses a low-energy-consumption water-cooling radiator for a large-scale cabinet, and the radiator comprises a cabinet which serves as a basic component and is used for bearing and connecting a lower structure; the radiator is arranged in the cabinet and is used for radiating heat of the cabinet body; the low-resistance connecting structure is connected with the cabinet and the radiator; the integrated heat dissipation structure is attached to the heating surface of the cabinet; the combined type circulation pipeline comprises a liquid inlet pipe, a liquid outlet pipe and a multi-stage flow divider, and the multi-stage flow divider is connected with an external cooling liquid supply system; and the self-adaptive flow control valve dynamically adjusts the flow of the cooling liquid according to the internal temperature of the cabinet. The invention has the following beneficial effects: when a cooling liquid flows through, the divergent cross section of the main flow channel layer accelerates fluid diffusion and reduces thermal resistance of a boundary layer, the flow deflectors and the spiral turbulent flow fins cooperate to make the cooling liquid better contact with the nano hydrophilic coating, the nano hydrophilic coating reduces a liquid drop contact angle, the cooling liquid forms an ultrathin liquid film on the flow channel wall, and the heat resistance of the boundary layer is improved. And vaporization latent heat release is accelerated.

The invention discloses a low-dielectric-constant polyamide material, and relates to the technical field of high polymer materials. The invention discloses a low-dielectric-constant polyamide material. The composite material is prepared from the following raw materials in parts by weight: 35 to 45 parts of polyamide 66, 5 to 10 parts of polytetrafluoroethylene micro powder, 8 to 12 parts of modified porous siloxane microspheres, 3 to 7 parts of modified nano zinc oxide, 10 to 15 parts of glass fibers, 4 to 8 parts of polyether-ether-ketone, 1 to 3 parts of graphene nanosheets, 3 to 5 parts of fluororubber, 1 to 2 parts of a titanate coupling agent, 0.3 to 0.7 part of an antioxidant 1010, 0.5 to 1.0 part of ethylene bis stearamide and 0.1 to 0.3 part of an ultraviolet absorbent UV-531. The low-dielectric-constant polyamide material has the remarkable advantages that the raw materials are scientifically proportioned, and various modified components are contained to enhance the performance; all the components are subjected to special treatment, so that the compatibility is good; the preparation process is rigorous, and the material has excellent dielectric properties; and the material also has good heat resistance and weather resistance and strong mechanical properties, and is suitable for various scenes with high dielectric constant requirements.

The invention discloses a composite material with a shielding function, a preparation method thereof and an interphone shell. The composite material comprises a polycarbonate-acrylonitrile-butadiene-styrene copolymer, a modified conductive filler, maleic anhydride grafted polyethylene, polyaryletherketone, a flame retardant, an antioxidant, glass microfibers and a compatilizer, wherein the modified conductive filler is aluminum oxide ceramic particles subjected to chemical copper plating and graft polymerization treatment. The preparation method comprises the steps of modified conductive filler preparation, step-by-step raw material mixing, twin-screw extrusion granulation and drying. The interphone shell is prepared from the composite material through injection molding, and the injection molding process comprises the steps of raw material drying, injection molding machine preheating, charging and injection molding, and demolding and finishing. The composite material is stable in electromagnetic shielding performance and has good mechanical strength and heat resistance; the preparation method can improve the dispersity of the components and is adaptive to conventional equipment; the interphone shell can block electromagnetic wave interference, is suitable for being used in multiple environments, and meets the requirements of an electronic equipment shell for shielding and structural performance.

An object is to provide a resin composition having a high permittivity and a low dissipation factor, and having excellent heat resistance and moisture absorption and heat resistance, and suitably used for producing an insulation layer of a printed wiring board, and a prepreg, a resin sheet, a laminate, a metal foil-clad laminate, and a printed wiring board obtainable by using the resin composition. The resin composition of the present invention contains (A) a surface coated titanium oxide in which a mass reduction rate in heating from 30° C. to 300° C. at a heating rate of 10° C. / min is 0.5 mass % or less, and (B) a thermosetting compound.