24results about How to "Improves ablation resistance" patented technology

The invention discloses an ablation-resistant EPDM (Ethylene-Propylene-Diene Monomer) thermal insulation material and a preparation method thereof, and belongs to the field of thermal insulation materials, the thermal insulation material is prepared from the following components in parts by mass: 70 to 80 parts of EPDM rubber, 20 to 30 parts of liquid EPDM, 15 to 20 parts of silicon dioxide, 10 to 40 parts of high-temperature-resistant filler, 10 to 15 parts of flame retardant, 10 to 15 parts of heat-resistant fiber and 3 to 5 parts of cross-linking agent. A third monomer of the ethylene propylene diene monomer is ethylidene norbornene, and the ethylene content is 50-60%. The raw materials are placed between double rollers to be mixed, and a mixed sheet is obtained; and performing vulcanization molding on the mixed sheet to obtain the ablation-resistant ethylene-propylene-diene monomer thermal insulation material. The content of the heat-resistant fibers is increased, the aramid fibers are subjected to in-situ carbonization to form a carbonized layer structure frame, and meanwhile, the content of SiO2 is regulated and controlled, so that the content of SiO2 is matched with the increase of the fibers, and the ablation resistance of the thermal insulation material is improved.

The invention provides a flame-retardant PP material with high strength and high modulus and a preparation method thereof. The flame-retardant PP material comprises the following raw materials in percentage by weight: 30-60% of polypropylene resin; 20 to 30% of a flame retardant; 20 to 30% of short glass fiber; 5-10% of a filling material; 5-10% of a compatilizer; and 2-3 wt% of other auxiliary agents. By compounding the piperazine halogen-free flame retardant, the glass fiber and the inorganic mineral powder, the tensile strength of the obtained polypropylene composite material reaches 69-75 MPa, the bending modulus reaches 5000-5400 MPa, and the tensile strength and the bending modulus are higher than general requirements of new energy battery materials; the flame retardant grade can reach 1.5 V0 of UL94, and the flame retardant grade requirements of most new energy batteries are met.

The invention relates to a layered cathode structure based on functional layer-buffer layer alternate distribution and a rapid trial-manufacturing method thereof, and belongs to the technical field of machining, the layered cathode structure comprises a functional structure surface layer and a matrix, and the functional structure surface layer is further formed by stacking and alternately arranging a plurality of sub functional layers and buffer layers. In actual service, a refractory oxide layer is generated in situ on the basis of the functional layer made of the thermochemical material, self-protection is completed, and electrons are emitted to support arc discharge; and the buffer layer is made of a nanocrystalline material with high plastic deformation capacity, so that the thermal stress of the functional layer can be released through proper deformation of the buffer layer, and meanwhile, cathode spot migration can be accelerated when the buffer layer is in contact with a cathode arc so as to slow down cathode burning loss. Through the synergistic effect of the functional layer and the buffer layer, the problems of cracking, splitting and coating falling caused by plasma discharge shock heating and shock cooling of the layered cathode in application scenes such as electric spark machining hole making and electric arc welding are solved, meanwhile, the ablation uniformity is improved, and the ablation rate is reduced.

The application discloses a high-temperature curing ablation-resistant and heat-insulating two-component coating and a preparation process. The coating is composed of A component and B component. The A component comprises modified epoxy resin, liquid butyronitrile rubber, aluminum hydroxide powder, chromium trioxide, high-silica fiber powder, hollow glass microbead and toluene; the B component is a curing agent and a curing accelerator. In the preparation, the aluminum hydroxide powder, the chromium trioxide, the high-silica fiber powder and the hollow glass microbead are made into a filler dispersion liquid; then the epoxy resin and the liquid butyronitrile rubber are made into a resin-rubber mixture; then the filler dispersion liquid is slowly and uniformly added into the resin-rubber mixture under stirring, and the A component is obtained by soaking in a static magnetic field at room temperature and grinding; the curing agent and the curing accelerator are the B component. By optimizing the coating composition, the ablation resistance and the heat-insulating performance of the coating can be obviously improved by coating a single layer, the construction process is simplified, the coating thickness is reduced, and the high-temperature resistance of the coating is improved.

The invention discloses a titanium plate elastic grinding block material and a titanium plate elastic grinding block. The titanium plate elastic grinding block material is prepared from, by mass, 20%-25% of boron modified phenolic resin, 20%-25% of cardanol modified phenolic resin, 5%-8% of diamond, 10%-15% of silicon carbide, 5%-10% of white corundum, 5%-10% of potassium titanate whiskers, 5%-10% of basic magnesium sulfate whiskers and 8%-18% of filler. According to the titanium plate elastic grinding block material, the boron modified resin is selected, so that the temperature resistance of the grinding block can be improved, and the basic magnesium sulfate whiskers with flame retardance and cooling and heat dissipation performance are added, so that the high-temperature working performance of the grinding block is improved; moreover, cardanol modified phenolic resin is selected, so that the toughness and impact resistance of the grinding block can be improved, and potassium titanate whiskers are added, so that the strength and toughness of a matrix are improved, the holding force on diamond is improved, the wear resistance of a product is improved, and the cost performance is improved.

This invention provides a castable ablation-resistant coating material and its preparation method. The material is composed of unsaturated polyester resin, cobalt naphthenate, cyclohexanone peroxide, trichloroethyl phosphate, boron phenolic resin, silicon carbide, and hexa(4-aldehyde phenoxy)cyclotriphosphazene. Through optimized compounding design of the coating material, this invention achieves a castable ablation-resistant coating material with an ablation rate as low as 0.11 mm / s and a viscosity as low as 5900 mPa·s. This material possesses both excellent ablation resistance and casting process performance, and has broad application prospects in the casting and coating of solid rocket motor propellants.

The application provides a preparation method of an electrode part applied to a single crystal hot field device, which comprises the following steps: mixing cobalt powder, iron powder and carbon fiber particles to obtain a first mixed powder; mixing cobalt powder, copper powder, iron powder and carbon fiber particles to obtain a second mixed powder; filling the first mixed powder into a cavity of a mold, and making the volume of the first mixed powder account for 1 / 3-1 / 2 of the volume of the cavity; filling the second mixed powder into the cavity of the mold, and making the second mixed powder fill the cavity of the mold; performing die forming so that the first mixed powder and the second mixed powder jointly form an electrode green body; and sintering the electrode green body to obtain an electrode part. The electrode part has the excellent performance of both carbon / carbon composite material and cobalt-copper alloy material. The application further provides an electrode part prepared by the preparation method.

The invention discloses a modified aramid nanofiber / rubber composite material and a preparation method thereof.Aramid nanofibers with good water dispersibility are prepared through epoxy modification, the in-situ polycondensation effect of a silicate ester compound on the surfaces of the nanofibers is improved through a nucleophilic substitution reaction of epoxy groups and amino groups, ANFs (at) SiO2 is formed, and the modified aramid nanofiber / rubber composite material is prepared. The composite material with excellent physical and mechanical properties and ablation resistance can be obtained by using the ANFs (at) SiO2 reinforced rubber with lower parts by weight. In the ablation process, the nano silicon dioxide is firstly melted to form a protective film to coat the surface of the aramid nano fiber, so that the aramid nano fiber is prevented from being corroded and decomposed by heat flow, ceramic structures such as SiC and Si3N4 are generated in situ to promote densification of a carbon layer, and the ablation resistance of the rubber is remarkably enhanced.

This invention belongs to the field of ablation-resistant thermal insulation composite material preparation technology, specifically relating to a polyacrylonitrile-based hollow carbon fiber for thermal protection materials and its preparation method. The invention first pre-oxidizes porous polyacrylonitrile precursor fibers to obtain porous pre-oxidized fibers. Then, phenolic resin is coated onto the surface of the pre-oxidized fibers through solution polymerization. After impregnation in an organosilicon source solution, rapid Joule heating at high temperature deposits both phenolic carbon microspheres with excellent ablation resistance and a silica coating on the fiber surface, forming a unique hollow carbon fiber structure with excellent thermal insulation properties. This solves the problem that polyacrylonitrile-based carbon fibers cannot simultaneously achieve both thermal insulation and ablation resistance. The thermal conductivity of the polyacrylonitrile-based hollow carbon fiber prepared by this method is about 17% lower than that of porous polyacrylonitrile carbon fibers prepared by traditional carbonization methods, making it applicable to the field of integrated ablation-resistant thermal protection materials.

The application provides a high-conjugated aromatic core structure epoxy resin modified silicone rubber and a preparation method and application thereof, and belongs to the technical field of advanced materials. The high-conjugated aromatic core structure epoxy resin is used for modifying the silicone rubber, so that the mechanical property, thermal stability and heat oxidation resistance of the silicone rubber are improved, and the ordered arrangement of carbon and the growth of ceramic phase can be promoted under extreme heat flow conditions, a more continuous and compact carbon-silicon composite protective layer is formed, and the ablation resistance of the silicone rubber is significantly improved. The modified silicone rubber has excellent mechanical property, thermal stability, heat oxidation resistance and heat protection capacity, and has important scientific significance and application value for expanding the application scene of the silicone rubber in the field of extreme ablation resistance and protection and promoting the development of a new generation of high-speed aircraft heat protection technology.

This invention discloses a silicate colloid for high-solids-content, high-modulus composite fire-resistant glass and its preparation method, relating to the field of composite fire-resistant glass technology. Specifically, it describes a silicate colloid for high-solids-content, high-modulus composite fire-resistant glass and its preparation method. The colloid, by weight percentage, comprises a silicon source, water, glycerol / ethylene glycol / polyethylene glycol / polyglycerol, water-soluble organic acids and salts, water-soluble metal oxides or hydroxides, and alkali metal hydroxides, wherein the solids content is 60-75% and the modulus is 4.0-5.5. The preparation method includes: uniformly mixing the silicon source, water, additives, and functional additives, then adding alkali metal hydroxides, reacting at 50-90°C to obtain a prepolymer solution, followed by vacuum degassing. The viscosity is adjusted to the desired range by controlling the reaction conditions. This prepolymer solution is suitable for pouring or coating processes. After curing, the colloid forms a fire-resistant glass core layer. The resulting fire-resistant glass has advantages such as high light transmittance, ultra-thinness, dense foaming, low-temperature resistance, high weather resistance, and long lifespan.

The invention discloses a preparation method of a low-temperature non-pressure rapid prototyping ultrahigh-temperature ceramic material, and belongs to the technical field of ultrahigh-temperature ceramics. The method comprises the following steps: dispersing polyzirconium dihydrogen phosphate powder in a mixed solvent of ethanol and water, adding F44 phenolic epoxy resin with the same mass, and concentrating to obtain an adhesive solution; and then compounding hafnium carbide powder with different particle sizes into the adhesive, selectively adding boron powder and silicon powder, uniformly mixing, removing the solvent, grinding and forming, and curing in an air environment without pressure to obtain the ultrahigh-temperature ceramic material. Polymeric zirconium dihydrogen phosphate is adopted as a novel curing agent, the problems that a traditional epoxy system is high in porosity and poor in heat resistance and ablation resistance are solved, and meanwhile the advantage of high bonding strength is reserved; the technology is low in temperature, free of pressure, easy and convenient to operate and rapid in forming, the ultrahigh-temperature ceramic material with high temperature resistance and ablation resistance is obtained, and the ultrahigh-temperature ceramic material is suitable for thermal protection in extreme thermal environments such as aerospace and the like.

The invention relates to the field of preparation of zirconium carbide workpieces, in particular to a zirconium carbide-based end cap and a preparation method thereof. Comprising the following steps: S1, preparing a preform: weaving a carbon fiber prepreg to prepare the preform; s2, preparation of a preparation body: depositing a BN interface layer and a SiC interface layer on the surface of the preform in the step S1 to prepare the preparation body; s3, preparation of a pre-finished product: putting the preparation body prepared in the step S2 into a vacuum heating furnace, mixing SiC and ZrC to form precursor slurry, adding the precursor slurry into the vacuum heating furnace, performing heating reaction, introducing reaction gas into the vacuum heating furnace in the reaction process, and enabling the reaction gas to react with oxygen; s4, cooling and taking materials; the purpose is to effectively improve the overall mechanical property of the prepared zirconium carbide-based end cap.

The invention discloses a heat-proof and heat-insulation composite material and a preparation method and application thereof, relates to the field of phenolic resin-based composite materials, and firstly provides a modified phenolic resin composition for the heat-proof and heat-insulation composite material, which comprises phenolic resin, a curing agent, a phenolic aldehyde modifier, a coupling agent and an organic solvent; and then impregnating fiber cloth with the modified phenolic resin composition to obtain a prepreg, laying the prepreg, and carrying out gradient heating hot-pressing curing treatment to obtain the heat-proof and heat-insulation composite material. The composite material has relatively low density, has mechanical properties, large heat flow ablation resistance and reusable performance, is suitable for being applied to a thermal protection system, and is particularly applied to thermal protection of the bottom of an outsole of a return type carrier rocket.

The application discloses a kind of thermosetting polyaryletherketone, composite material and the preparation method and application of thermosetting polyaryletherketone, belong to special polymer material field.The amino-containing crosslinkable thermosetting polyaryletherketone is synthesized by nucleophilic polycondensation reaction in the application.The thermosetting polyaryletherketone in the application can be self-crosslinked to form thermosetting polyaryletherketone product without adding crosslinking agent such as diamine monomer, and the influence of uneven distribution of crosslinking agent on thermosetting polyaryletherketone product is completely avoided.

The application relates to the technical field of ablation-resistant materials, in particular to a high-performance composite material and a preparation method thereof, which comprises the following steps: surface modification of coated carbon fibers and carbon nanotubes by using silane coupling agents respectively to obtain modified carbon fibers and modified carbon nanotubes; uniform stirring of polyphenyl ether resin, an antioxidant, anti-precipitation flame-retardant microspheres and the modified carbon nanotubes to obtain a mixture; side feeding of the modified carbon fibers in a double-screw extruder, extrusion granulation and preparation of the high-performance composite material. By adding the coated carbon fibers, the anti-precipitation flame-retardant microspheres and the carbon nanotubes in the resin matrix, the ablation resistance and the friction resistance of the prepared composite material are greatly improved; specifically, the zirconium oxide film is coated on the surface of the carbon fibers, the coated carbon fibers have the characteristics of high-temperature oxidation resistance, corrosion resistance and high hardness, and the coated carbon fibers and the carbon nanotubes jointly act, so that the overall performance of the composite material is enhanced.

The invention relates to the technical field of polyphenyl ether composite materials, in particular to an in-situ polymerization reaction extrusion device and method.The method comprises the steps that cuprous bromide, di-n-butylamine and methylbenzene are added into a reaction kettle to be stirred and dissolved; 2, 6-dimethylphenol and nano-zirconia are added into the reaction kettle, toluene is supplemented, and stirring is continued; introducing oxygen into the reaction kettle for reaction; adding sufficient methanol into the reaction kettle for precipitation to form a mixed material liquid in the reaction kettle; the mixed material liquid is injected into the packing auger through the material conveying pipe, the liquid enters the liquid storage tank along the filter plate, the separated precipitate continues to move, enters the screw extruder after being dried by the heating jacket, and is extruded and granulated to prepare the polyphenyl ether composite resin material. The nano zirconium oxide is added in the in-situ polymerization process of the polyphenyl ether, so that the nano zirconium oxide can be uniformly dispersed in a resin matrix, the problems of agglomeration and non-uniform dispersion during later addition of the nano zirconium oxide are avoided, and the ablation resistance of the polyphenyl ether composite resin material can be improved.

The application discloses a tungsten-copper alloy reinforced by tungsten carbide grains and a preparation method thereof, and the method comprises the following steps: (1) drying carbon-modified tungsten-copper composite powder and placing the powder in a mold of a tablet press; (2) applying pressure to the powder in the step (1) to press a green body; (3) performing high-temperature sintering on the green body obtained in the step (2) under an argon atmosphere to obtain the tungsten-copper alloy reinforced by tungsten carbide grains; and (4) performing mechanical processing on the tungsten-copper alloy to manufacture an electric contact of a circuit breaker. Thus, the tungsten-copper alloy is prepared by the method, in-situ carburization of tungsten surface is performed by using carbon without additional tungsten carbide grains, and abnormal growth of the tungsten carbide grains in the sintering process is effectively slowed down; a small amount of in-situ generated tungsten carbide grains avoids the limitation of unqualified indexes such as alloy brittleness and low density caused by unevenness of traditional additional tungsten carbide grains, and the prepared tungsten-copper alloy has high strength, high wear resistance and high-temperature ablation resistance.

The present application relates to the technical field of gas detection, and provides an inert gas measuring device, which comprises a laser, a first beam splitter, a hollow cathode discharge cavity, two optical filters, two photodetectors and a data acquisition card; the laser is used for emitting laser; the first beam splitter is used for splitting the laser into two beams, one of which is emitted to one photodetector after passing through the hollow cathode discharge cavity and one optical filter, and the other of which is emitted to the other photodetector after passing through the other optical filter; the hollow cathode discharge cavity is filled with inert gas; the data acquisition card is connected with the two photodetectors and is used for collecting signals of the two photodetectors and outputting the metastable particle number density in the hollow cathode discharge cavity. The scheme can improve the plasma density generated by discharge and the metastable atom conversion efficiency, reduce the detection limit under the condition of ensuring the measurement accuracy, and accurately measure the inert gas content.

This invention discloses a fire control blanket for extinguishing fires in new energy batteries. The fire control blanket is characterized by being composed of a layer of high-silica glass fiber cloth and a layer of high-oxygen-index pre-oxidized fiber cloth. The high-silica glass fiber cloth has a silica weight content ≥96%, and the pre-oxidized fiber cloth has an oxygen index greater than 45%. The fire control blanket provides breathability through the composite structure of the high-silica glass fiber cloth and the pre-oxidized fiber cloth to release flammable gases generated by battery fires, and filters burning particles when covering open flames. It fully utilizes the heat insulation, non-combustibility, high-temperature resistance, ease of use, and breathability of the high-silica glass fiber cloth and the high-oxygen-index fiber cloth. This can solve the problem of deflagration or explosion caused by the accumulation of large amounts of flammable gases released from new energy battery fires, and can filter out burning particles to purify the air, reduce the adsorption of harmful particles, and achieve the advantages of being environmentally friendly and non-toxic.

The invention discloses a tungsten carbide grain reinforced tungsten-copper alloy and a preparation method thereof.The method comprises the steps that 1, carbon modified tungsten-copper composite powder is dried and then placed in a mold of a tablet press; (2) applying pressure to the powder in the step (1), and pressing into a green body; (3) carrying out high-temperature sintering on the green body obtained in the step (2) in an argon atmosphere to obtain the tungsten carbide grain reinforced tungsten-copper alloy; and (4) machining the tungsten-copper alloy to manufacture the electrical contact of the circuit breaker. Therefore, by adopting the method for preparing the tungsten-copper alloy, in-situ carburization can be carried out on the tungsten surface by utilizing carbon under the condition that tungsten carbide grains are not additionally added, and abnormal growth of the tungsten carbide grains in the sintering process is effectively slowed down; a small amount of tungsten carbide crystal grains are generated in situ, the limitation of unqualified indexes such as alloy brittleness and low density caused by non-uniform traditional additional tungsten carbide crystal grains is avoided, and the prepared tungsten-copper alloy has high strength, high wear resistance and high-temperature ablation resistance.

The invention relates to the technical field of wires and cables, and specifically to a fire-resistant building wire and cable and a preparation method thereof. A mica tape, a cross-linked polyethylene insulation layer, and a tear-resistant fiber reinforcement layer are wrapped on the outer surface of a copper core to form an oxygen-isolating layer of a combined core. A plurality of combined cores are wrapped together with a mica tape layer, and flame-retardant alkali-free glass fiber as a filler is filled in the plurality of combined cores and the mica tape layer to obtain a cable core. Then, a tear-resistant fiber reinforcement layer and an outer sheath that is low-smoke, halogen-free, flame-retardant and has self-healing ability are sequentially coated on the outside of the cable core; magnesium hydroxide is modified; and a self-healing elastomer is introduced into the outer sheath, thereby greatly extending the service life of the wire and cable.