21 results about "Boron fiber" patented technology

The invention belongs to the technical field of velvet glaze preparation, and particularly relates to high-texture velvet glaze and a preparation process thereof. By optimizing the raw material formula, such as adopting kaliophilite high-strontium frit, modified boron fiber, hydroxyapatite powder and the like and process parameters, the comprehensive performance of the velvet glaze is remarkably improved. The kaliophilite high-strontium frit prepared by the invention is subjected to pre-melting treatment, so that components such as KO, SrO and the like are uniformly dispersed in the form of a glass phase, local segregation is avoided, and a microcrystalline network induced by hydroxyapatite powder is matched, so that the glossiness of a glaze surface is stabilized at 16-18 degrees, the surface roughness Ra is less than or equal to 0.3 mu m, and the touch feeling is silky and soft; the cerium acetate modified boron fiber is adopted to form cerium oxide attached to the surface of the boron fiber, so that the binding force with a glaze interface is improved, the raw materials are uniformly dispersed, fiber agglomeration is avoided, and the touch feeling of the glaze is improved; the raw materials promote the stability of the glaze in the sintering process through a synergistic effect, and a solution is provided for industrial application of the high-texture velvet glaze.

The invention belongs to the technical field of neutron radiation protection, and discloses a flexible neutron radiation protection material and a preparation method thereof. Comprising a high-density polyethylene / modified boron nitride composite fabric, and the surface of the composite fabric is coated with a polymer / boron powder composite coating. The preparation method comprises the following steps: (1) preparing modified boron nitride; (2) preparing a polyethylene / boron nitride blend; (3) spinning polyethylene / boron nitride fibers; (4) weaving the fabric; (5) preparing a coating dispersion liquid; and (6) fabric coating treatment. The shielding efficiency of the product prepared by the invention at a 5.3-wavelength neutron absorption position can reach 50.9-78%, and the protection requirement of neutron radiation is met; the surface coating of the composite fabric obtained after batch production is good in quality, and the composite fabric has good popularization significance.

The invention provides a preparation method of a boron nitride fiber reinforced ceramic-based composite material, and belongs to the technical field of boron nitride fiber reinforced ceramic-based composite materials. The preparation method comprises the steps of mixed slurry preparation, fiber cloth pretreatment, coating curing and sintering. The step of preparing the mixed slurry comprises the steps of preparing silicon-boron-oxygen-nitrogen powder, coating and pulping; the preparation method of the silicon-boron-oxygen-nitrogen powder comprises the following steps: mixing tetraethoxysilane and absolute ethyl alcohol, uniformly stirring, dropwise adding trimethyl borate at a dropwise adding rate of 1-2 mL / min while maintaining a stirring speed of 480-520 r / min, adjusting the pH value to 3-4 after dropwise adding, adding hexamethyldisilazane, stirring at 40-50 DEG C for 2-3 h to obtain sol, standing, aging, drying and roasting to obtain the silicon-boron-oxygen-nitrogen powder. The silicon-boron-oxygen-nitrogen powder is obtained; the composite material prepared through the method is high in mechanical property, good in high temperature resistance and excellent in long-term service performance.

The application discloses a temperature self-balancing fine stone concrete and a preparation method thereof, and belongs to the technical field of building materials. The concrete comprises the following components in parts by weight: cementing material, high-thermal-conductivity and high-heat-storage aggregate, fine stone, sand, high-thermal-conductivity boron nitride fiber, water and additive. The preparation method of the high-thermal-conductivity and high-heat-storage aggregate is as follows: S1. uniformly mixing coal gangue, fly ash and mineral powder, adding pore-forming agent and water, aging, granulating, sintering and then obtaining high-heat-storage fine stone ceramsite; S2. uniformly mixing cement, fly ash and mineral powder, adding water and stirring, then adding boron nitride powder, uniformly mixing to obtain a slurry, and then adding the high-heat-storage fine stone ceramsite into the slurry, and taking out and curing to obtain the high-thermal-conductivity and high-heat-storage aggregate. The high-thermal-conductivity and high-heat-storage aggregate and the high-thermal-conductivity boron nitride fiber are introduced into the concrete, and the two components are used in combination to improve the rapid temperature change response capability of the fine stone concrete, so that the internal temperature gradient of the fine stone concrete is self-balanced with the change of the external temperature.

The invention discloses a rotor magnet yoke assembly and processing equipment thereof, the rotor magnet yoke assembly comprises an outer ring and an inner ring fixed with the inner wall of the outer ring through a connecting rib, and the outer ring is provided with a plurality of heat dissipation holes; and the outer ring comprises the following raw materials in percentage by weight: 75-82% of aluminum alloy, 8-12% of nano aluminum nitride, 3-5% of nano boron fiber and the balance of additives. In the application, the outer ring mainly adopts the aluminum alloy as the raw material, the light weight and structural strength of the outer ring are realized, the heat-conducting property of the outer ring is greatly improved through the synergistic effect of the nano aluminum nitride and the nano boron fibers, and a high-efficiency heat dissipation system is formed in cooperation with the plurality of heat dissipation holes in the outer ring; meanwhile, the structural design that the inner ring and the outer ring are fixed through the connecting ribs guarantees the overall stability of the assembly, the temperature rise problem of the novel energy automobile driving motor under high-power-density operation is effectively solved, and then the working reliability of the driving motor is improved.

This invention relates to the field of coating technology, specifically to anti-condensation coatings, methods of application, and coating apparatus. The anti-condensation coating includes an individually packaged coating body and an individually packaged surface spray powder. The surface spray powder comprises nano-sized boron fiber powder, nano-sized graphene powder, and nano-sized metal oxide powder, wherein the nano-sized metal oxide powder is at least one of nano-sized cerium oxide powder, nano-sized yttrium oxide powder, and nano-sized neodymium oxide powder. Such an anti-condensation coating has the advantage of better anti-condensation effect. The anti-condensation coating coating apparatus includes a frame, a first roller wound with cable raw material wire, a second roller wound with coated cable wire, a first coating chamber, and a second coating chamber. Such an anti-condensation coating coating apparatus also has the advantage of being able to apply the anti-condensation coating.

This invention discloses a method for repairing local defects in carbon fiber reinforced ceramic matrix composites, characterized by the following steps: preparing a first fiber slurry, comprising carbon fiber, water glass, and ceramic powder; preparing a second fiber slurry, comprising long-fiber boron nitride fibers, ceramic powder, and solvent; preparing a third fiber slurry, comprising short-fiber boron nitride fibers, ceramic powder, polymer monomers, crosslinking agent, initiator, and solvent; impregnating the local defect in the carbon fiber reinforced ceramic matrix composite with the first fiber slurry, filling 60-80% of the defect; then filling with the second fiber slurry, filling the remaining 60-80% of the defect, and then squeezing out excess solvent; then filling with the third fiber slurry to fill the defect, and then curing at room temperature. This method achieves rapid repair of local defects in carbon fiber reinforced ceramic matrix composites without the need for high-temperature heating.

The utility model discloses a tunnel kiln with novel heat preservation structure relates to tunnel kiln technical field, a tunnel kiln with novel heat preservation structure, include: tunnel kiln main part, the tunnel kiln main part includes charging delivery platform, the inside of tunnel kiln main part is provided with heat insulating layer, the inside of heat insulating layer is provided with heat preservation layer, the inside of heat preservation layer is provided with heat -resisting layer, the heat insulating layer includes asbestos layer, the inside of asbestos layer is provided with nitrogen layer boron fiber board layer, and the thickness of asbestos layer is same with the thickness of nitrogen layer boron fiber board layer, and the heat preservation layer includes aluminium silicate refractory board layer, and the inside of aluminium silicate refractory board layer is provided with mullite material layer. The tunnel kiln of existing has solved, and the heat preservation effect is poor, when people use tunnel kiln, is easy to cause internal temperature loss too fast, leads to energy consumption to be too high, increases use cost, and the technical problem of inconvenient people's use is solved.

The invention provides a surface coating preparation method of a boron nitride fiber reinforced ceramic matrix composite material and a product prepared by the surface coating preparation method, and relates to the field of ceramic materials. The preparation method of the surface coating of the boron nitride fiber reinforced ceramic-based composite material comprises the following steps: sintering to prepare a ceramic repair layer, vapor deposition to prepare a ceramic compact layer, and spraying and curing to prepare a surface smooth layer. According to the preparation method of the surface coating of the boron nitride fiber reinforced ceramic matrix composite material, on the premise that the wave-transparent performance of the composite material is not affected, the matching performance of the surface coating and the composite material is good, and the surface coating and the composite material can be effectively combined; the surface coating can uniformly form a film on the surface of the composite material, surface defects of the composite material are effectively filled, and the air tightness of the composite material is good; and meanwhile, the surface coating also has anti-pollution performance.

The invention provides an aluminum-based silicon carbide composite plate strip, and relates to the technical field of plate strips, a high-temperature transition layer is used for realizing gradient transition of high-temperature resistance and thermal stress, can effectively relieve high-temperature temperature difference stress between a zirconium modified pure aluminum anti-cracking main body layer and the high-temperature transition layer of a plate, and avoids deformation and cracking of the whole structure of the plate due to overlarge cold and hot gradient; the low-temperature buffer layer is matched with the boron fiber enrichment transition layer, so that the high-temperature-resistant strength of the transition area can be further improved, the boron fiber enrichment transition layer is prevented from structural instability at high temperature, the low-temperature buffer layer can realize gradient transition of low-temperature resistance and stress, and the low-temperature shrinkage stress of the lower layer of the plate can be effectively relieved; the temperature-resistant composite main body layer can bear the stress of all upper-layer structures and uniformly disperse the stress to the whole region, stable support is provided for all upper-layer functional structures, meanwhile, the temperature resistance of the temperature-resistant composite main body layer is complementary with the temperature-resistant and low-temperature-resistant structures of all the layers, and finally the comprehensive effects of heat resistance, cold resistance, cracking resistance and protection of the plate are achieved.

The invention designs a preparation method of an emulsion sizing agent for boron nitride fibers, which comprises the following steps: S11, mixing polyethylene glycol and 4-diphenylmethane diisocyanate, and heating for the first time in the presence of a catalyst to obtain PEG / MDI system polyurethane; s12, mixing the PEG / MDI system polyurethane with phenol, and heating for the second time in the presence of a catalyst to obtain modified polyurethane; s21, the modified polyurethane and bisphenol A epoxy resin are mixed, stirred and heated, and epoxy resin premixed liquid is obtained; s31, adding a nonionic surfactant and a flatting agent into the epoxy resin premixed solution, and stirring and heating to obtain a sizing premixed solution; s41, adding deionized water into the sizing premixed liquid, and stirring to obtain the emulsion sizing agent for the ceramic fibers; polyethylene glycol is added as a linear molecular polymer and forms a spring effect with the hard chain segment MDI, so that the wear resistance of the boron nitride fiber is improved; wettability between the sizing agent and the boron nitride fibers is good, and bundling of the boron nitride fibers is facilitated.

The application belongs to the technical field of aerospace materials, and provides a continuous boron fiber reinforced aluminum alloy matrix composite material, which is prepared by laying and hot isostatic pressing of boron fiber precursor filaments; the boron fiber precursor filaments comprise boron fiber filaments, a B4C layer, a Ti layer and an aluminum alloy layer which are sequentially deposited on the boron fiber filaments. The application introduces a B4C / Ti double coating layer on the boron fiber filaments, improves the interface bonding strength between the reinforcing boron fiber and the aluminum alloy matrix, and also maintains the integrity of the boron fiber; so that the interface bonding strength and the tensile strength of the continuous boron fiber reinforced aluminum alloy matrix composite material are significantly improved. f Compared with the interface bonding strength and the tensile strength of the B4C / Al matrix composite material without introducing the B4C / Ti double coating layer, the interface bonding strength and the tensile strength of the continuous boron fiber reinforced aluminum alloy matrix composite material are significantly improved, which has important significance for meeting the strong demand for lightweight high-strength materials in the field of aerospace.

The invention discloses a high-buffering and heat-insulating mica composite part for a new energy vehicle battery, and the high-buffering and heat-insulating mica composite part comprises a buffering and heat-insulating layer which is used for buffering and heat insulating, is arranged at the bottom of a mica layer and is used for improving thermal runaway protection of a lithium battery cell module; according to the invention, through the arrangement of the buffer thermal insulation layer, the damping and basic thermal insulation capabilities of the composite part are greatly improved, the vibration impact when the battery cell works or is out of control can be buffered, the boron nitride fiber layer and the expanded graphite are mounted in the second organic silicon modified polyurethane foaming buffer thermal insulation layer, and when thermal runaway occurs, the expanded graphite is combusted to form carbon residues, so that the thermal runaway is avoided. Boron nitride fibers and a second organic silicon modified polyurethane foaming buffering and heat-insulating layer are covered with the first organic silicon modified polyurethane foaming buffering and heat-insulating layer, so that the flame-retardant and fireproof performance of a composite part is greatly improved, the damping and heat-insulating capacity of the composite part is enhanced, and the thermal runaway protection effect on a lithium battery cell module is effectively improved; and the safety of the battery of the new energy vehicle and the safety of a driver are better guaranteed.

This invention provides a high-conversion boron nitride fiber and its continuous preparation method and system. The method includes: spinning a boron nitride organic precursor to obtain precursor fiber; guiding the precursor fiber to a coating zone to coat it with protective oil, obtaining precursor fiber with a protective oil layer on its surface; guiding the precursor fiber with the protective oil layer to an oil control zone for oil control, controlling the oil content to a preset value, obtaining oil-controlled precursor fiber; guiding the oil-controlled precursor fiber to an inert atmosphere multi-temperature zone for sequentially performing protective oil layer curing treatment and boron nitride organic precursor fiber thermal stability treatment; guiding the thermally stabilized precursor fiber to a reaction atmosphere multi-temperature zone for sequentially performing degreasing treatment and sintering treatment, obtaining boron nitride fiber. The preparation method of this invention eliminates upstream and downstream disconnection in each process, enabling continuous production; the protective oil combined with the temperature zone design allows for precise control of the timing of fiber protection, improving the conversion rate.

The invention discloses halogen-free flame-retardant nylon. The halogen-free flame-retardant nylon is prepared from the following raw materials: matrix resin, a heat-resistant agent, a flame retardant and a functional auxiliary agent, the heat-resistant agent is functionalized nano boron fiber, and the raw materials of the functionalized nano boron fiber comprise nano boron fiber, trichloromethylsilane and black phosphorus nanosheets; the flame retardant is gradient type hyperbranched polyol, and the hyperbranched polyol is prepared from the following raw materials: trimethylolpropane, diphenyl phosphate, epoxy chloropropane, glycidyl stearate and tetrabutylammonium bromide. The invention provides halogen-free flame-retardant nylon as well as a preparation method and application thereof. The flame retardant property, the mechanical property and the upper limit of heat resistance of the halogen-free flame-retardant nylon can be improved.

The invention provides a preparation method of hydroxyl boron nitride fibers and propane oxidative dehydrogenation application of the hydroxyl boron nitride fibers. The invention provides a hydroxyl boron nitride fiber preparation method, which comprises: (1) dissolving boric acid and melamine in deionized water, carrying out recrystallization at a temperature of 85 DEG C, and carrying out vacuum drying to obtain a white precursor; (2) calcining the obtained precursor at high temperature to obtain boron nitride fibers; and (3) carrying out normal-temperature chemical activation treatment on the obtained boron nitride fiber to obtain the hydroxyl boron nitride fiber. The method has the advantages of being wide in raw material source, low in cost, simple and convenient in preparation method, capable of realizing large-scale synthesis, simplified in freeze drying step and capable of avoiding high-temperature hydroxylation treatment. The advantages of more defects and larger specific surface area are realized; and the hydroxyl boron nitride fiber obtained by the invention has excellent performance when being used for the oxidative dehydrogenation reaction of propane.

The invention discloses a preparation method of wear-resistant polytetrafluoroethylene, and relates to the technical field of high polymer materials, the wear-resistant polytetrafluoroethylene is prepared from the following raw materials by weight: 80-90 parts of polytetrafluoroethylene resin, 10-20 parts of acrylic acid modified polyether-ether-ketone, 1-3 parts of graphene oxide quantum dots, 1-3 parts of a coupling agent, 8-12 parts of nanoparticles, and 3-5 parts of nano boron fibers. The polytetrafluoroethylene is excellent in wear resistance, sufficient in performance stability and processability and long in service life.

The invention discloses a high-temperature-resistant boron nitride fiber sleeve and a preparation method and application thereof, and belongs to the technical field of ceramic fiber sleeves, the preparation method comprises the steps of slurry preparation, forming and post-treatment; the step of preparing the slurry comprises the following steps: treating boron nitride fibers, hydroxylating, treating powder, compounding and mixing; the step of treating the boron nitride fibers comprises the following steps: mixing the boron nitride fibers, hydroxyethyl cellulose and water, stirring at room temperature, filtering, taking filter residues, and drying; compounding: mixing the treated boron nitride fiber and water, stirring at room temperature, adding the treated powder dispersion liquid, stirring after the addition is finished, adding the hydroxyethyl cellulose aqueous solution, stirring after the addition is finished, filtering, taking filter residues, and drying; the prepared high-temperature-resistant boron nitride fiber sleeve is good in high temperature resistance, insulativity and breakdown resistance, good in crease resistance and durability and free of sparking hidden danger in application.

The utility model discloses an electrical energy-saving control switch, and relates to the field of control switches. An electrical energy-saving control switch comprises a control switch main body, the lower end of the control switch main body is fixedly connected with a mounting plate, the surface of the control switch main body is provided with a flame-retardant layer, the surface of the flame-retardant layer is provided with a heat insulation layer, the surface of the heat insulation layer is provided with a corrosion-resistant layer, the flame-retardant layer comprises a ceramic fiber layer, and the ceramic fiber layer is arranged on the surface of the heat insulation layer. The heat insulation layer comprises a ceramic fiber layer, a basalt fiber layer is arranged on the surface of the ceramic fiber layer, the thickness of the basalt fiber layer is the same as that of the ceramic fiber layer, the heat insulation layer comprises a PSU plastic layer, and a nitrogen boron fiber layer is arranged on the surface of the PSU plastic layer. The technical problems that an existing control switch does not have a flame-retardant function, when people use the control switch for a long time and poor contact occurs at the connecting position of a switch contact piece and a wire, hot smoking and sparks can occur, short circuit can be caused, and then the control switch is on fire are solved.

The invention discloses a low-temperature self-heat-sealing single-material PVC packing material and a preparation method thereof, and belongs to the technical field of high polymer materials. The packaging material comprises a heat sealing layer, a base layer and a functional coating which are sequentially stacked, and each layer takes polyvinyl chloride as a compatible matrix. The heat sealing layer comprises polyvinyl chloride resin, an ethylene-vinyl acetate copolymer and a GPE type modified material, and low-temperature heat sealing of 70-80 DEG C is achieved; the base layer comprises polyvinyl chloride resin and nano boron fibers, so that the packing material is endowed with high mechanical strength; the functional coating contains a waterborne polyurethane dispersion and nano SiO2, and provides excellent barrier properties. According to the invention, the technical contradiction that the traditional PVC packaging material is easy to degrade due to high-temperature heat sealing and the multi-layer composite material is difficult to recover is solved, and an innovative packaging solution with low-temperature processability, high performance and complete recoverability is provided.

The invention provides a boron nitride fiber, a preparation method thereof and a heat-conducting composite material. The device with the confinement space is used as a reaction place of the boron nitride fibers, the concentration of reactants in the reaction process is controlled, the diffusion path of the reactants is limited, uniform deposition of the boron nitride fibers is achieved, and the purity is improved; meanwhile, the transition metal magnesium oxide and the transition metal iron oxide are used as precursors to catalyze the boron nitride fiber, so that the shape of the boron nitride fiber is regulated and controlled. The boron nitride fiber prepared by the invention has high length-diameter ratio and anisotropic thermal conductivity, a longer network path can be constructed in matrix resin, so that the boron nitride fiber has excellent interface bonding capacity with the matrix resin, the interface thermal resistance is small, and the prepared thermal conductive composite material has excellent thermal conductivity, mechanical property and electrical property and is suitable for industrial production. The radiator can be widely applied to heat dissipation of electronic devices.