12results about How to "Improves ablation resistance" patented technology

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.

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.

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 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 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.