An ultra-high temperature resistant refractory material and a preparation method thereof

Abstract

This invention provides an ultra-high temperature resistant refractory material and its preparation method, relating to the field of refractory and high temperature resistant materials technology. The ultra-high temperature resistant refractory material comprises an aggregate system, an aerogel system, a flame retardant system, a binder system, and a pore-forming agent system. The aggregate system contains 25-30 parts by weight of an aerogel that has undergone atmospheric high temperature and high pressure (2000℃) treatment. 0 C) Burned, finely ground meteorite powder and its substitutes, wherein the meteorite powder, after being activated by atmospheric high-temperature, high-pressure oxidation plasma, produces an aggregate of hydrogen-helium-silicon-calcium nonmetallic alloys with a particle size of 0.5μm to 5μm, along with various trace atomic alloys such as Fe-Ni, Ti-Ni, Ti-Cr, and Zr-Cr, forming an ultra-high temperature refractory aggregate. Furthermore, the Fe-Ni, Ti-Ni, Ti-Cr, and Zr-Cr trace alloys utilize the unique trace element alloy phases in the meteorite powder as natural sintering aids and catalysts, constructing a chemical sintering mechanism within the material. Through catalytic action, it exhibits high temperature resistance (3000...). 0 (C and above) It is corrosion resistant, has high damping, and improves the stability of refractory delay, breaking through the industry bottleneck of high temperature resistance of ultra-high temperature ceramics and opening up a new research topic in the field of refractory materials.

Description

Technical Field

[0001] This invention relates to the field of refractory and high-temperature resistant materials technology, specifically to an ultra-high temperature resistant refractory material and its preparation method. Background Technology

[0002] With the rapid development of aerospace, new energy, and extreme manufacturing, the industry has placed almost stringent demands on thermal protection materials. These materials not only need to withstand instantaneous ultra-high temperatures exceeding 3000℃ or long-term heat flux exceeding 2000℃, but also need to possess extremely low thermal conductivity to prevent heat transfer to the internal components of equipment. Especially in the military and deep space exploration fields, materials must maintain structural integrity and dimensional stability under the coupled environment of aerodynamic heating and particle irradiation. Currently, mainstream high-temperature resistant materials are mainly divided into two categories: oxide ceramic systems and ultra-high temperature ceramic systems. Oxide ceramic systems and ultra-high temperature ceramic systems constitute the two main branches of the modern advanced ceramic materials family. Oxide ceramic systems, with their excellent electrical insulation properties, chemical stability, and thermal stability, are used in electronics, energy, and chemical industries.

[0003] Existing ultra-high temperature refractory materials still have some problems. Although ultra-high temperature ceramics can withstand temperatures of over 3000 degrees Celsius, they are brittle, like glass, and break easily. On the other hand, existing thermal insulation materials on the market also have obvious shortcomings. Some are extremely hard but cannot be further processed, making it difficult to drill holes or cut corners. Others are made too soft in pursuit of low density and cannot provide structural support. Therefore, those skilled in the art provide an ultra-high temperature refractory material and its preparation method to solve the problems mentioned in the background. Summary of the Invention

[0004] (a) Technical problems to be solved To address the shortcomings of existing technologies, this invention provides an ultra-high temperature resistant refractory material and its preparation method. This solves the problems that while ultra-high temperature ceramics can withstand temperatures of over 3000 degrees Celsius, they are also brittle, like glass, and break easily. On the other hand, existing thermal insulation materials on the market also exhibit significant shortcomings. Some are extremely hard but cannot be further processed, making it difficult to drill holes or cut corners. Others are made too soft and flimsy in pursuit of low density, failing to provide structural support.

[0005] (II) Technical Solution To achieve the above objectives, the present invention is implemented through the following technical solution: an ultra-high temperature resistant refractory material, comprising an aggregate system, a cementing system, a flame retardant system, a binder system, and a pore-forming agent; The aggregate system comprises 25-30 parts by weight of meteorite powder, which is activated by oxygen plasma, resulting in the in-situ growth of trace element iron-nickel-titanium-zirconium-chromium alloy phases (Fe-Ni-S), (Ti-Ni), (Ti-Cr), and (Zr-Cr) with a particle size of 0.5 μm to 5 μm on its surface. The surface area to volume ratio (S / V) of the iron-nickel-titanium-zirconium-chromium alloy phase is ≥1.5 μm. -1 ; The aerogel system is composed of 20-25 parts by weight of fine aluminum dihydrogen phosphate powder; The flame retardant powder is composed of 5-10 parts by weight of ammonium dihydrogen phosphate flame retardant powder; The adhesive consists of 1-3 parts by weight of lanthanum oxide crosslinked PVA adhesive; The pore-forming agent is composed of 1-3 parts by weight of sodium bicarbonate microspheres modified with stearic acid or borate-modified polyethylene polypropylene. During the 600℃-800℃ heat treatment stage, the iron-nickel-titanium-zirconium-chromium alloy phase acts as a Lewis acid catalyst, inducing a topological chemical reaction of aluminum dihydrogen phosphate at the aggregate interface. This results in in-situ self-assembly of a 2μm-10μm thick layer of aluminum pyrophosphate nanoneedle-like whiskers with a normal infrared emissivity ≥0.92. These whisker layers are staggered with the matrix at a 45°-60° angle, causing a negative exponential decay in the backwall heat flux density under a continuous heat source of 1000℃. Within the 600℃-800℃ heat treatment window, these active metal sites induce phosphorus… Aluminum dihydrogen phosphate undergoes an in-situ topological chemical reaction, self-assembling and growing a layer of aluminum pyrophosphate nanoneedle-like whiskers with a thickness of 2μm-10μm on the surface of the lubricant. This microstructure endows the material with extremely high normal infrared emissivity, completely subverting the heat storage logic of traditional thermal insulation materials and realizing a negative heat flux density effect. Under the action of a continuous heat source, the material no longer heats up, but actively dissipates heat through infrared radiation. The measured cooling rate is no less than 5℃ / min, truly achieving cooling down the more it is heated, providing a physical basis for high-energy laser protection at 10,000 degrees and blocking battery thermal runaway.

[0006] Preferably, the pore-forming agent undergoes controlled decomposition at 100℃-300℃, releasing trace amounts of CO2 gas and forming a closed pore array with a pore size distribution of 0.5μm-5μm inside the material. The porosity of the closed-pore array is controlled between 35% and 45%, and the pore wall surface is coated with nano-radiative units derived from the aluminum pyrophosphate whisker layer, resulting in an effective thermal conductivity of the material at 1000℃ ranging from 0.08 W / (m·K) to 0.12. Within the W / (m·K) range and with a thermal hysteresis time constant ≥300s, a controlled decomposition mechanism was constructed by introducing stearic acid-coated modified sodium bicarbonate microspheres as a pore-forming agent. The stearic acid coating layer precisely controlled the decomposition temperature of sodium bicarbonate, slowly releasing trace amounts of CO2 within the 100℃-300℃ range, thereby forming a uniformly distributed array of closed pores inside the material. This solid-gas bimodal distribution structure greatly increases the path resistance of heat conduction and effectively blocks gas convection heat transfer. The effective thermal conductivity of the material at 1000℃ is locked in an extremely low range of 0.08W / (m·K) to 0.12W / (m·K), while the thermal hysteresis time constant ≥300s significantly delays the penetration of heat to the back wall and improves the thermal buffering capacity of the equipment.

[0007] Preferably, the aggregate system further comprises 5-10 parts by weight of ammonium dihydrogen phosphate flame retardant powder, wherein the specific surface area of ​​the ammonium dihydrogen phosphate powder is 800-1000 m². 2 / g; The aluminum dihydrogen phosphate and ammonium dihydrogen phosphate undergo esterification with the hydroxyl groups in the boric acid crosslinked polyvinyl alcohol fiber, forming a "Si-OC" covalent bridging network with a node density ≥10. 6 pcs / mm 3 To suppress grain boundary slip at high temperatures, the "Si-OC" covalent bond bridging network formed after the hydrolysis of the silane coupling agent firmly bridging the inorganic aerogel powder with boric acid crosslinked polyvinyl alcohol fibers. This interface bridging mechanism eliminates the slip defects between interfaces of traditional composite materials, allowing stress to be uniformly transmitted between the matrices. This endows the material with both rigidity and flexibility, maintaining the high hardness of refractory materials on the surface to resist erosion, while the matrix possesses toughness and plasticity. The material can be cut and drilled arbitrarily like wood without chipping, greatly reducing the construction difficulty of aerospace curved parts and complex battery modules.

[0008] Preferably, the nano-carbon dots formed by the complete carbonization of the boric acid cross-linked polyvinyl alcohol fiber at temperatures above 500°C produce a synergistic effect with the iron-nickel alloy phase through π-d orbital coupling. The synergistic effect enables the material to withstand more than 50 rapid cooling and heating cycles from 1100℃ to room temperature, with a residual compressive strength retention rate of ≥90% after the cycles. At high temperatures, the π electron cloud of nano carbon dots overlaps with the d orbitals of the iron-nickel-titanium-zirconium-chromium alloy, forming a π-d orbital coupling effect. This microscopic electronic coupling can absorb and dissipate the crack propagation energy generated during thermal shock, inhibit the initiation of microcracks, and maximize the material's thermal shock resistance. It can withstand more than 50 rapid cooling and heating cycles from 1100℃ to room temperature without cracking, and the residual compressive strength retention rate is ≥90%, which greatly extends the service life of industrial kilns and military equipment under extreme temperature differences.

[0009] Preferably, in the test of burning the material with an oxyacetylene flame at 1000°C for 1 hour, the back wall temperature does not exceed 200°C. As the burning time increases, the proportion of radiative heat transfer in the aluminum pyrophosphate nanoneedle whisker layer increases to more than 70% of the total heat transfer, and the material body temperature exhibits a logarithmic decay trend, achieving a cooling rate of not less than 5°C / min as it is heated. As the burning time increases, the proportion of radiative heat dissipation in the total heat transfer gradually increases to more than 70%, exceeding the input of heat conduction, resulting in a logarithmic decay trend in the material body temperature. This provides a quantifiable safety threshold. In the test of burning the material with an oxyacetylene flame at 1000°C for 1 hour, the back wall temperature is strictly controlled below 200°C. This provides definitive data support for the thermal safety protection of new energy battery packs and effectively prevents the chain propagation of thermal runaway.

[0010] A method for preparing ultra-high temperature resistant refractory materials includes the following steps: S1. Meteorite activation: Meteorite powder is placed in a low-temperature plasma jet device with a power of 300W-500W and treated for 10-30 minutes to generate dangling bonds on its surface and expose active sites of iron, nickel, titanium, zirconium and chromium metals. S2. Rheology-controlled mixing: Aluminum dihydrogen phosphate solution was mixed with boric acid-modified PVA solution, and the pH was adjusted to 4.0-5.0. The mixture was then subjected to ultrasonic-shear dispersion for 30 minutes under a vacuum of -0.08 MPa to -0.1 MPa. Perform ultrasonic-shear composite dispersion treatment for 30 minutes. This forms a non-Newtonian fluid slurry with a thixotropic index (TI) of 3.0-4.5. S3. Gradient curing employs a three-stage temperature control process. First, wet curing is carried out at 60℃-80℃, followed by constant temperature at 150℃ for 2 hours to remove crystal water, and finally, crystal transformation sintering is performed in an inert atmosphere at 1100℃-1300℃ for 3-5 hours. Through oxygen plasma activation treatment, the passivation layer on the surface of meteorite micro powder is removed, exposing highly active metal sites, significantly reducing the sintering activation energy of the phosphate system. Combined with the gradient curing process, an orderly transition from low-temperature physical crosslinking to high-temperature chemical bonding is achieved, breaking the industry bottleneck that ultra-high temperature ceramics must be sintered above 2000℃. The sintering temperature is reduced to the conventional range of 1100℃-1300℃, saving more than 40% of production energy consumption. At the same time, it avoids grain coarsening caused by high temperature and ensures the fineness of the microstructure.

[0011] Preferably, in the crystal transformation sintering stage of step S3, the heating rate is controlled at 5℃ / min, and the temperature is held at 800℃ for 1 hour to induce the iron-nickel alloy phase to catalyze the formation of needle-shaped aluminum pyrophosphate whiskers. The whiskers are inserted into the gaps between the aggregates at an angle of 45°-60° to form a three-dimensional interlocking structure, which greatly improves the mechanical strength of the material. The needle-shaped whiskers rivet the aggregates like nails, which increases the compressive strength of the material by 30% and effectively inhibits creep and shrinkage at high temperatures.

[0012] Preferably, after step S2, a vacuum slurry kneading step is also included, in which the slurry is squeezed and degassed 3-5 times using a three-roll mill to control the volatile content of the slurry to below 0.5wt%, thereby eliminating bubbling defects during the sintering process of the material. This completely solves the bubbling and warping defects in the sintering process of large-size plates, increasing the yield from 60% in the traditional process to over 95%, and meeting the yield requirements of large-scale industrial production.

[0013] (III) Beneficial Effects This invention provides an ultra-high temperature resistant refractory material and its preparation method. It has the following beneficial effects: 1. In this invention, the unique trace iron-nickel-titanium-zirconium-chromium alloy phase in meteorite micropowder is used as a natural sintering aid and catalyst to construct a low-temperature catalytic sintering mechanism inside the material. Traditional ultra-high temperature ceramics must rely on high-temperature sintering above 2000℃, which consumes a lot of energy. However, this invention can achieve densification and whisker growth of the material at only 1100℃-1300℃ through catalysis. This not only significantly reduces production energy consumption and equipment wear by more than 40%, but also breaks through the industry bottleneck that ultra-high temperature ceramics must be fired at high temperatures, and realizes low-cost large-scale preparation.

[0014] 2. In this invention, the aluminum pyrophosphate nanoneedle whisker layer formed by in-situ self-assembly endows the material with extremely high infrared emissivity. Unlike the heat accumulation effect of traditional materials that get hotter the longer they are heated, this material, when burned in a 1000℃ flame, not only maintains a back wall temperature below 200℃, but also exhibits a negative temperature rise characteristic of getting cooler the longer it is heated. This is because the material actively dissipates the heat accumulated inside in the form of infrared radiation, rather than simply relying on blocking, thus fundamentally blocking the propagation path of thermal runaway.

[0015] 3. In this invention, π-d orbital coupling is used to enhance interfacial bonding, combined with a gradient porosity structure design, resulting in a hard material surface and a surface area to volume ratio (S / V) of the iron-nickel-titanium-zirconium-chromium alloy phase ≥ 1.5 μm. -1 The internal toughening network eliminates the brittleness of ceramics. Unlike traditional refractory bricks that require mold pressing, this material can be cut, drilled, and bent on the construction site like wood or plastic boards without breaking, greatly reducing the installation difficulty and construction cost of irregular parts.

[0016] 4. In this invention, the micron-sized closed pores formed by the decomposition of the pore-forming agent buffer the stress generated by thermal expansion and contraction. The material can withstand more than 50 cycles of rapid cooling and heating from 1100℃ to room temperature without cracking or peeling. Compared with the defects of traditional oxide ceramics that are prone to cracking, this invention significantly improves the service life and safety of the equipment under extreme working conditions. It is particularly suitable for military and deep space exploration equipment where temperature differences change drastically. Detailed Implementation

[0017] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0018] Example 1: This invention provides a durable Ultra-high temperature refractory materials, including aggregate systems, cementing systems, flame retardant systems and pore-forming agents; The aggregate system contains 25-30 parts by weight of meteorite powder. The meteorite powder is activated by oxygen plasma, and trace element iron-nickel alloy phases (Fe-Ni-S), titanium-nickel alloy, titanium-chromium alloy, and zirconium-chromium alloy phases with a particle size of 0.5μm to 5μm grow in situ on its surface. The surface area to volume ratio (S / V) of the iron-nickel-titanium-zirconium-chromium alloy phase is ≥1.5μm. -1 ; The gelling system consists of 20 parts by weight of aluminum dihydrogen phosphate micro powder and 1-3 parts by weight of lanthanum oxide cross-linked polyvinyl alcohol fiber; The pore-forming agent consists of 1-3 parts by weight of stearic acid-coated modified sodium bicarbonate microspheres and 1-3 parts by weight of polyethylene polypropylene; the coating layer thickness is 50nm-200nm. During the 600℃-800℃ heat treatment stage, the iron-nickel alloy phase acts as a Lewis acid catalyst, inducing a topological chemical reaction at the aggregate interface of aluminum dihydrogen phosphate. This results in in-situ self-assembly of a 2μm-10μm thick layer of aluminum pyrophosphate nanoneedle-like whiskers with a normal infrared emissivity ≥0.92. The whisker layer is staggered with the matrix at an angle of 45°-60°, causing a negative exponential decay in the backwall heat flux density under a continuous heat source of 1000℃. Within the 600℃-800℃ heat treatment window, these active metal sites induce a topological reaction in aluminum dihydrogen phosphate. Aluminum undergoes an in-situ topological chemical reaction, self-assembling and growing a layer of aluminum pyrophosphate nanoneedle-like whiskers with a thickness of 2μm-10μm on the aggregate surface. This microstructure endows the material with extremely high normal infrared emissivity, completely subverting the heat storage logic of traditional thermal insulation materials and realizing a negative heat flux density effect. Under the action of a continuous heat source, the material no longer heats up, but actively dissipates heat through infrared radiation. The measured cooling rate is no less than 5℃ / min, truly achieving cooling down the more it is heated, providing a physical basis for high-energy laser protection and battery thermal runaway prevention.

[0019] The pore-forming agent undergoes controlled decomposition in the 100℃-300℃ range, releasing trace amounts of CO2 gas and forming a closed pore array with a pore size distribution of 0.5μm-5μm inside the material. The porosity of the closed-pore array is controlled between 35% and 45%, and the pore wall surface is coated with nano-radiative units derived from aluminum pyrophosphate whisker layers, which locks the effective thermal conductivity of the material at 1000℃ between 0.08 W / (m·K) and 0.12. Within the W / (m·K) range and with a thermal hysteresis time constant ≥300s, a controlled decomposition mechanism was constructed by introducing stearic acid-coated modified sodium bicarbonate microspheres as a pore-forming agent. The stearic acid coating layer precisely controlled the decomposition temperature of sodium bicarbonate, slowly releasing trace amounts of CO2 within the 100℃-300℃ range, thereby forming a uniformly distributed array of closed pores inside the material. This solid-gas bimodal distribution structure greatly increases the path resistance of heat conduction and effectively blocks gas convection heat transfer. The effective thermal conductivity of the material at 1000℃ is locked in an extremely low range of 0.08W / (m·K) to 0.12W / (m·K), while the thermal hysteresis time constant ≥300s significantly delays the penetration of heat to the back wall and improves the thermal buffering capacity of the equipment.

[0020] The aggregate system also contains 5-10 parts by weight of ammonium dihydrogen phosphate, and the specific surface area of ​​the ammonium dihydrogen phosphate flame retardant powder is 800-1000 m². 2 / g; Aluminum dihydrogen phosphate and ammonium dihydrogen phosphate undergo esterification with the hydroxyl groups in boric acid-crosslinked polyvinyl alcohol fibers, forming a "Si-OC" covalent bridging network with a node density ≥10. 6 pcs / mm 3 To suppress grain boundary slip at high temperatures, the "Si-OC" covalent bond bridging network formed after the hydrolysis of silane coupling agent firmly bridging the inorganic aerogel powder with boric acid crosslinked polyvinyl alcohol fibers. This interface bridging mechanism eliminates the slip defects between interfaces of traditional composite materials, allowing stress to be uniformly transmitted between the matrices. This endows the material with both rigidity and flexibility, maintaining the high hardness of ceramics to resist erosion, while the matrix possesses the toughness and plasticity of metals. The material can be cut and drilled arbitrarily like wood without chipping, greatly reducing the construction difficulty of aerospace curved parts and complex battery modules.

[0021] The nano-carbon dots formed by the complete carbonization of boric acid cross-linked polyvinyl alcohol fibers at temperatures above 500℃ produce a synergistic effect with the iron-nickel-titanium-zirconium-chromium alloy phase through π-d orbital coupling. The synergistic effect increases the number of rapid cooling and heating cycles from 1100℃ to room temperature to more than 50, and the residual compressive strength retention rate after the cycle is ≥90%. At high temperature, the π electron cloud of nano carbon dots overlaps with the d orbitals of the iron-nickel-titanium-zirconium-chromium alloy, forming a π-d orbital coupling effect. This microscopic electronic coupling can absorb and dissipate the crack propagation energy generated during thermal shock, inhibit the initiation of microcracks, and improve the thermal shock resistance of the material to the extreme. It can withstand more than 50 rapid cooling and heating cycles from 1100℃ to room temperature without cracking, and the residual compressive strength retention rate is ≥90%, which greatly extends the service life of industrial kilns and military equipment under extreme temperature differences.

[0022] In the test of burning the material in an oxyacetylene flame at 1000℃ for 1 hour, the back wall temperature did not exceed 200℃. As the burning time increased, the radiative heat transfer ratio of the aluminum pyrophosphate nanoneedle whisker layer increased to more than 70% of the total heat transfer, and the material body temperature showed a logarithmic decay trend, achieving a cooling rate of no less than 5℃ / min as it was heated. As the burning time increased, the proportion of radiative heat dissipation in the total heat transfer gradually increased to more than 70%, exceeding the input of heat conduction, resulting in a logarithmic decay trend in the material body temperature. This provides a quantifiable safety threshold. In the test of burning the material in an oxyacetylene flame at 1000℃ for 1 hour, the back wall temperature was strictly controlled below 200℃. This provides definitive data support for the thermal safety protection of new energy battery packs and effectively prevents the chain propagation of thermal runaway.

[0023] A method for preparing ultra-high temperature resistant refractory materials includes the following steps: S1. Meteorite activation: Meteorite powder is placed in a low-temperature plasma jet device with a power of 300W-500W and treated for 10-30 minutes to generate dangling bonds on its surface and expose active sites of iron, nickel, titanium, zirconium and chromium metals. S2. Rheology-controlled mixing: Aluminum dihydrogen phosphate micro powder and boric acid modified PVA micro powder are mixed with water, and the pH value is adjusted to 4.0-5.0. Ultrasonic-shear composite dispersion is carried out for 30 minutes under vacuum conditions of -0.08MPa to -0.1MPa to form a non-Newtonian fluid slurry with a thixotropic index (TI) of 3.0-4.5. S3. Gradient curing employs a three-stage temperature control process. First, wet curing is carried out at 60℃-80℃, followed by constant temperature at 150℃ for 2 hours to remove crystal water, and finally, crystal transformation sintering is performed in an inert atmosphere at 1100℃-1300℃ for 3-5 hours. Through oxygen plasma activation treatment, the passivation layer on the surface of meteorite micro powder is removed, exposing highly active metal sites, significantly reducing the sintering activation energy of the phosphate system. Combined with the gradient curing process, an orderly transition from low-temperature physical crosslinking to high-temperature chemical bonding is achieved, breaking the industry bottleneck that ultra-high temperature ceramics must be sintered above 2000℃. The sintering temperature is reduced to the conventional range of 1100℃-1300℃, saving more than 40% of production energy consumption. At the same time, it avoids grain coarsening caused by high temperature and ensures the fineness of the microstructure.

[0024] In the crystal transformation sintering stage of step S3, the heating rate is controlled at 5℃ / min, and the temperature is held at 800℃ for 1 hour to induce the iron-nickel-titanium-zirconium-chromium alloy phase to catalyze the formation of needle-shaped aluminum pyrophosphate whiskers. The whiskers are inserted into the gaps between the aggregates at an angle of 45°-60° to form a three-dimensional interlocking structure, which greatly improves the mechanical strength of the material. The needle-shaped whiskers rivet the aggregates like nails, which increases the compressive strength of the material by 30% and effectively inhibits creep and shrinkage at high temperature.

[0025] After step S2, a vacuum slurry mixing step is also included, in which the slurry is squeezed and degassed 3-5 times using a three-roll mill to control the volatile content of the slurry to below 0.5wt%, thereby eliminating bubbling defects during the sintering process of the material. This completely solves the bubbling and warping defects in the sintering process of large-size plates, increasing the yield from 60% in the traditional process to over 95%, meeting the yield requirements of large-scale industrial production.

[0026] Example 2: This embodiment is based on Embodiment 1: a rigid large plate for aerospace thermal protection.

[0027] The target characteristics are extreme resistance to laser ablation and structural strength.

[0028] Formula composition: Meteorite micro powder activated by oxygen plasma: 30 parts by weight (particle size D50=5μm); Aluminum dihydrogen phosphate powder: 20 parts by weight (specific surface area 950 m²) 2 / g); Ammonium dihydrogen phosphate powder: 10 parts by weight; Lanthanum oxide powder: 3 parts by weight; stearic acid-coated sodium bicarbonate microspheres or boric acid and polyethylene polypropylene: 1.5-2 parts by weight; (PVA) adhesive: 3 parts by weight; water: appropriate amount. In the preparation process, bone powder is first placed in a container, followed by aluminum dihydrogen phosphate and ammonium dihydrogen phosphate. Then, lanthanum oxide and polyethylene polypropylene are placed in separate containers and slowly stirred evenly with wooden chopsticks. Next, glue is added, and then an appropriate amount of water is added and stirred until it becomes a paste. Let it stand for 10 minutes.

[0029] Preparation process: According to S1. Meteorite activation, meteorite powder is placed in a low-temperature plasma jet device with a power of 300W-500W for 10-30 minutes to generate dangling bonds on its surface and expose active sites of iron, nickel, titanium, zirconium and chromium metals. S2. Stirring material variable control mixing: Fine aluminum dihydrogen phosphate powder is mixed with boric acid and lanthanum oxide modified powder, sodium bicarbonate or polyethylene polypropylene and water are added, the pH value is adjusted to 4.0-5.0, and ultrasonic-shear composite dispersion is carried out for 10 minutes under vacuum conditions of -0.08MPa to -0.1MPa to form a non-Newtonian fluid slurry with a thixotropic index (TI) of 3.0-4.5. S3. Gradient curing adopts a three-stage temperature control process. First, wet curing is carried out at 60℃-80℃, then the crystal water is removed by constant temperature at 150℃ for 2 hours, and finally crystal transformation sintering is carried out in an inert atmosphere at 1100℃-1300℃ for 3-5 hours. In the S3 gradient curing stage, the temperature is held at 800℃ for 1 hour to promote the growth of needle-like whiskers, and then the temperature is raised to 1300℃ for sintering for 3 hours.

[0030] Employing a 10000℃-level CO2 laser (power density 10 4 W / cm 2 After irradiation for 60 seconds, the results showed that the material surface only underwent slight ablation without perforation, and the peak temperature of the back wall was only 185℃. SEM observation revealed that a large number of aluminum pyrophosphate whiskers with a length of 5-10μm were interspersed at a 45° angle to form a dense three-dimensional interlocking structure, proving that it has excellent resistance to high-energy particle erosion.

[0031] Example 3: This embodiment is based on Embodiment 1: a flexible thermal insulation pad for new energy vehicle batteries.

[0032] The target characteristics are ultra-low thermal conductivity, anomalous cooling effect, and customizability.

[0033] Formula composition: Meteorite micro powder activated by oxygen plasma: 30 parts by weight (particle size D50=10μm, coarser to reduce density): Aluminum dihydrogen phosphate powder: 20 parts by weight (aerogel); Ammonium dihydrogen phosphate (flame retardant powder): 10 parts by weight; Lanthanum oxide powder (binder) 3 parts by weight Polyethylene polypropylene: 2 parts by weight (high fiber content to improve toughness); Stearic acid-coated sodium bicarbonate microspheres: 3 parts by weight. (Pore-forming agent) Preparation process: The process is the same as in Example 1, but the sintering temperature is adjusted to 1150℃ to avoid excessively high temperatures from damaging the aerogel structure. In step S2, the thixotropic index (TI) of the slurry is controlled to be 4.0 to ensure that it has a certain degree of flexibility after molding.

[0034] The sample was attached to the nozzle of a 1000℃ flame gun and burned for 1 hour. The results showed that the temperature of the material body gradually decreased from the initial 190℃ to 165℃, while the temperature of the back wall stabilized at 180℃. The material has moderate hardness and can be cut into any shape with ordinary scissors. There was no powdering or cracking at the edges, making it very suitable for filling the gaps between power battery modules.

[0035] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A high-temperature resistant refractory material, characterized in that: This includes aggregate systems, aerogel systems, flame retardant systems, PVA binder systems, and pore-forming agent systems. The material system comprises 25-30 parts by weight of non-metallic fine powder from stony meteorite. This meteorite powder undergoes oxygen plasma activation treatment, resulting in in-situ growth of various trace element alloy phases with particle sizes ranging from 0.5 μm to 5 μm, including Fe-Ni-S, Ti-Ni, Ti-Cr, and Zr-Cr alloys. Furthermore, the surface area to volume ratio (S / V) of these Fe-Ni-Ti-Cr alloy phases is ≥1.5 μm. -1 ; The gelling system consists of 20-25 parts by weight of aluminum dihydrogen phosphate powder and 1-3 parts by weight of lanthanum oxide binder adhesive. The flame retardant is composed of 5-10 parts by weight of ammonium dihydrogen phosphate. The pore-forming agent is composed of 1-3 parts by weight of sodium bicarbonate and borate polyethylene polypropylene. During the heat treatment stage at 600℃-800℃, the trace iron-nickel-titanium-chromium-zirconium alloy phase acts as a Lewis acid catalyst, inducing aluminum dihydrogen phosphate to undergo a topological chemical reaction at the aggregate interface, forming an in-situ self-assembly layer of aluminum pyrophosphate nanoneedle-like whiskers with a thickness of 2μm-10μm and a normal infrared emissivity ≥0.

92. The whisker layer is staggered with the matrix at an angle of 45°-60°, causing the back wall heat flux density of the material to exhibit a negative exponential decay under a continuous heat source of 1000℃.

2. The ultra-high temperature resistant refractory material according to claim 1, characterized in that: The pore-forming agent undergoes controlled decomposition at 100℃-300℃, releasing trace amounts of CO2 gas and forming a closed pore array with a pore size distribution of 0.5μm-5μm inside the material. The porosity of the closed pore array is controlled between 35% and 45%, and the surface of the pore wall is coated with nano-radiative units derived from the aluminum pyrophosphate whisker layer, so that the effective thermal conductivity of the material at 1000℃ is locked in the range of 0.08 W / (m·K) to 0.12 W / (m·K), and the thermal hysteresis time constant is ≥300s.

3. The ultra-high temperature resistant refractory material according to claim 1, characterized in that: The material system also contains 5-10 parts by weight of ammonium dihydrogen phosphate flame-retardant fine powder, the specific surface area of ​​which is 800-1000 m². 2 / g; The aerogel powder surface is grafted with γ-methacryloyloxypropyltrimethoxysilane (KH-570), whose double bonds undergo esterification with the hydroxyl groups in the boric acid crosslinked polyvinyl alcohol fiber to form a "Si-OC" covalent bridging network with a node density ≥10. 6 pcs / mm 3 It is used to suppress grain boundary slip at high temperatures.

4. The ultra-high temperature resistant refractory material according to claim 1, characterized in that: The nano carbon dots formed by the complete carbonization of the boric acid cross-linked polyvinyl alcohol fiber at above 500°C produce a synergistic effect with the iron-nickel-titanium-zirconium-chromium alloy phase through π-d orbital coupling. The synergistic effect enables the material to undergo more than 50 rapid cooling and heating cycles from 1100°C to room temperature, and the residual compressive strength retention rate after the cycles is ≥90%.

5. The ultra-high temperature resistant refractory material according to claim 1, characterized in that: In the test of burning the material in an oxyacetylene flame at 1000℃ for 1 hour, the back wall temperature did not exceed 200℃. Moreover, as the burning time increased, the material body temperature showed a logarithmic decay trend because the radiative heat transfer ratio of the aluminum pyrophosphate nanoneedle whisker layer increased to more than 70% of the total heat transfer, and the cooling rate was no less than 5℃ / min.

6. A method for preparing an ultra-high temperature resistant refractory material, using an ultra-high temperature refractory material as described in any one of claims 1 to 5, characterized in that: Includes the following steps: S1. Meteorite activation: Meteorite powder is placed in a low-temperature plasma jet device with a power of 300W-500W and treated for 10-30 minutes to generate dangling bonds on its surface and expose active sites of iron, nickel, titanium, zirconium and chromium metals. S2. Rheology-controlled mixing: Fine aluminum dihydrogen phosphate powder is mixed with boric acid-modified PVA solution, and the pH value is adjusted to 4.0-5.

0. The mixture is then ultrasonically mixed under a vacuum of -0.08 MPa to -0.1 MPa. Ultrasonic treatment was performed under conditions ranging from -0.08 MPa to -0.1 MPa. Shear-dispersed for 30 minutes, a non-Newtonian fluid slurry with a thixotropic index (TI) of 3.0-4.5 is formed; S3. Gradient curing adopts a three-stage temperature control process. First, wet curing is carried out at 60℃-80℃, then the crystal water is removed by constant temperature at 150℃ for 2 hours, and finally crystal transformation sintering is carried out in an inert atmosphere at 1100℃-1300℃ for 3-5 hours.

7. The method for preparing an ultra-high temperature resistant refractory material according to claim 6, characterized in that: In the crystal transformation sintering stage of step S3, the heating rate is controlled at 5℃ / min and held at 800℃ for 1 hour to induce the iron-nickel-titanium-zirconium-chromium alloy phase to catalyze the formation of needle-shaped aluminum pyrophosphate whiskers. The whiskers are inserted into the gaps between the aggregates at an angle of 45°-60° to form a three-dimensional interlocking structure.

8. The method for preparing an ultra-high temperature resistant refractory material according to claim 6, characterized in that: The process after step S2 also includes a vacuum slurry mixing step, in which the slurry is extruded and degassed 3-5 times using a three-roll mill to control the volatile content of the slurry to below 0.5 wt%, thereby eliminating bubbling defects during the sintering process of the material.

9. According to claim 12345678: A method for preparing ultra-high temperature resistant refractory material, characterized in that: This refractory coating is used to protect the surface of electronic components and critical areas of the outer casing of the transport equipment.