An amorphous refractory material containing nanoparticles and its preparation method

Abstract

This invention belongs to the field of refractory materials technology, specifically relating to an amorphous refractory material containing nanoparticles and its preparation method. The amorphous refractory material is composed of the following components in parts by weight: 60-70 parts alumina microparticles, 20-30 parts silicon carbide microparticles, 1-5 parts modified nano-graphite powder, 5-7 parts silica sol, 3-5 parts aluminate coupling agent, 4-7 parts modified carbon fiber, 2-5 parts short-cut mullite fiber, 2-3 parts rare earth composite stabilizer, 1-2 parts nano-titanium powder, 3-5 parts nano-ZrO2-Y2O3, and 2-4 parts composite antioxidant; the alumina microparticles have a particle size of 5-50 μm, and the silicon carbide microparticles have a particle size of 10-80 μm. The amorphous refractory material prepared by this invention exhibits excellent oxidation resistance, erosion resistance, and thermal shock resistance.

Description

Technical Field

[0001] This invention belongs to the field of refractory materials technology, specifically relating to an amorphous refractory material containing nanoparticles and its preparation method. Background Technology

[0002] Unshaped refractories, with their advantages of convenient construction, strong structural integrity, and controllable cost, are gradually replacing traditional fired shaped refractories in industries such as steel and metallurgy. However, with the increasing size of industrial equipment and the complex working conditions such as high-temperature oxidizing atmospheres and strong alkaline corrosion, existing unshaped refractories still have many shortcomings in terms of performance adaptability, application coverage, and production processes.

[0003] In steel industry blast furnaces and similar settings, the furnace gas often contains alkaline components such as sodium and potassium. Traditional corundum and corundum-mullite monolithic refractories are prone to reacting with these alkaline components, resulting in significant volume expansion. This can easily lead to material spalling, thinning of the furnace lining, and reduced service life. In the cement industry, equipment such as rotary kiln openings must withstand temperatures of 1000-1300℃ and frequent temperature fluctuations. Traditional monolithic refractories face the challenge of balancing high-temperature strength and thermal shock stability. While high-alumina castables can achieve high-temperature compressive strength exceeding 60MPa, their poor thermal shock stability makes them susceptible to cracking due to thermal stress. Lightweight insulating castables, while exhibiting excellent thermal shock performance, lack sufficient high-temperature strength to withstand the erosion of molten slag and iron.

[0004] Chinese patent application CN109485437A discloses an unshaped refractory material, which, by weight, comprises the following raw materials: 5-15 parts silicon carbide, 1-5 parts high-carbon raw material, 4-9 parts polypropylene, 8-15 parts surface treatment agent, 4-10 parts titanium, 10-25 parts stabilizer, 3-10 parts barium stearate, and 5-15 parts flame retardant. This technical solution contains components such as polypropylene and barium stearate, which have poor thermal stability. At high temperatures, the organic components decompose easily, generating gases that lead to the formation of pores within the material, reducing density and mechanical strength. Simultaneously, the decomposition of organic matter may damage the antioxidant layer formed by silicon carbide, thereby exacerbating erosion and oxidation of the material. Furthermore, the high-carbon raw material is prone to agglomeration and cannot be evenly distributed, failing to exert the anti-erosion effect of carbon and instead becoming a penetration channel for corrosive media, accelerating material failure. Summary of the Invention

[0005] Existing unshaped refractory materials suffer from poor thermal shock resistance and uneven dispersion of carbon-based materials. To address these issues, this invention provides an unshaped refractory material containing nanoparticles and its preparation method.

[0006] To achieve the objectives of this invention, the following technical solution is adopted:

[0007] In a first aspect, the present invention provides an amorphous refractory material containing nanoparticles, comprising the following components in parts by weight:

[0008] 60-70 parts alumina micro powder, 20-30 parts silicon carbide micro powder, 1-5 parts modified nano-graphite powder, 5-7 parts silica sol, 3-5 parts aluminate coupling agent, 4-7 parts modified carbon fiber, 2-5 parts short-cut mullite fiber, 2-3 parts rare earth composite stabilizer, 1-2 parts nano titanium powder, 3-5 parts nano ZrO2-Y2O3, and 2-4 parts composite antioxidant;

[0009] The alumina micro powder has a particle size of 5-50 μm, and the silicon carbide micro powder has a particle size of 10-80 μm.

[0010] By adopting the above technical solutions, alumina micropowder and silicon carbide micropowder form a continuous and dense matrix framework. Silica sol acts as an inorganic binder, forming a SiO2 ceramic bonding layer at high temperatures. This layer, in conjunction with an aluminate coupling agent, bridges the inorganic powder interface, enhancing matrix bonding and preventing strength reduction caused by interface peeling at high temperatures. Modified nano-graphite powder, nano-titanium powder, and nano-ZrO2-Y2O3 are dispersed in the matrix, exerting a nano-refining effect, reducing the material grain size, and increasing crack propagation resistance. The phase transformation toughening effect of nano-ZrO2-Y2O3 can absorb thermal stress, and combined with rare earth composite stabilizers, it inhibits grain growth, further improving the fracture toughness of the material and preventing cracks caused by impact or thermal stress during use. Modified carbon fiber and short-chopped mullite fiber are randomly distributed, forming a fiber bridging network that can hinder crack propagation. Mullite fiber is resistant to high temperatures and can alleviate internal stress caused by thermal expansion and contraction, reducing spalling failure caused by thermal shock.

[0011] Furthermore, the preparation method of the modified nano-graphite powder includes the following steps:

[0012] Nano-graphite powder, silane coupling agent, anhydrous ethanol and water are mixed in a mass-volume ratio of 10g:0.7-1.2g:80-120mL:10-12mL, ultrasonically dispersed, centrifuged and dried to obtain modified nano-graphite powder.

[0013] By adopting the above technical solution, the siloxane groups of the silane coupling agent are hydrolyzed to form silanol bonds, which are then chemically bonded to the surface of graphite powder, resulting in better compatibility with refractory material systems containing components such as silica sol.

[0014] Furthermore, the method for preparing the modified carbon fiber includes the following steps:

[0015] (1) Mix octaaminophenyl-POSS with epoxy-terminated borosilicate prepolymer evenly, degas under vacuum, heat to 80-100℃ for 1-2 hours, continue to heat to 120-150℃ for 3-5 hours to cure, and obtain POSS-borosilicate hybrid material.

[0016] (2) Mix POSS-borosilicate hybrid material with toluene at a mass-volume ratio of 1g:8-10mL to obtain a POSS-borosilicate hybrid material toluene solution;

[0017] (3) The carbon fiber is immersed in a toluene solution of POSS-borosilicate hybrid material, and after being immersed at a constant temperature, it is taken out and dried. It is then placed in a nitrogen and argon mixed atmosphere for gradient heating reaction, and cooled to room temperature to obtain modified carbon fiber.

[0018] By employing the above technical solution, the amino group of octaaminophenyl-POSS reacts with the epoxy group of the epoxy-terminated borosilicate prepolymer to form a hybrid material containing a POSS cage structure and a Si-OB crosslinked network. This material contains ceramic elements such as Si, B, O, and N. After pyrolysis, a dense SiBON composite ceramic coating is generated on the carbon fiber, effectively blocking the intrusion of oxidizing and corrosive media. Simultaneously, the SiBON ceramic coating covering the modified carbon fiber surface is a polar surface, capable of forming hydrogen bonds with components such as silica sol and alumina micropowder, reducing interfacial repulsion and making the carbon fiber more easily encapsulated by the matrix, thus reducing fiber agglomeration.

[0019] Further, in step (1), the mass ratio of octaaminophenyl-POSS to epoxy-terminated borosilicate prepolymer is 1:(8-12).

[0020] By adopting the above technical solution, this ratio can avoid the problems of insufficient crosslinking density due to excessive amino groups or coating defects caused by epoxy residues. At the same time, this ratio can ensure that the POSS cage structure is uniformly dispersed in borosilicate matrix, which not only avoids the aggregation of POSS due to excessive content, but also prevents the reduction of reinforcement and toughening effect due to excessively low content.

[0021] Furthermore, in step (3), the mass ratio of carbon fiber to toluene in the POSS-borosilicate hybrid material is (15-20):1.

[0022] By adopting the above technical solution, 15-20 parts of carbon fiber combined with 1 part of hybrid material can form a continuous SiBON ceramic coating on the surface of carbon fiber. After pyrolysis, it can effectively block oxidizing and corrosive media. If the ratio is too low, the hybrid material will be excessive, and the coating will be easy to fall off. If the ratio is too high, the hybrid material will be insufficient, and the coating will be discontinuous and exposed. This ratio can ensure that the carbon fiber bundle is uniformly covered and there are no local defects.

[0023] Further, in step (3), the heating reaction steps are as follows: heating to 80-90℃ at a heating rate of 1-2℃ / min and reacting for 9-10h, heating to 240-250℃ at a heating rate of 3-4℃ / min and reacting for 7-8h, and heating to 1500-1550℃ at a heating rate of 4-5℃ / min and reacting for 2-3h.

[0024] By adopting the above technical solution, the temperature is increased in a gradient manner, and the heating rate and holding time of each stage are coordinated to release internal stress and avoid coating cracking or delamination of carbon fiber from coating.

[0025] Furthermore, the rare earth composite stabilizer is prepared by mixing lanthanum oxide and yttrium oxide in a mass ratio of 1:(2-3).

[0026] By adopting the above technical solution, lanthanum oxide and yttrium oxide are both high-melting-point rare earth oxides. This ratio allows them to be uniformly dispersed in the refractory matrix, effectively inhibiting the growth of main crystalline phases such as alumina and silicon carbide at high temperatures and improving structural stability. They can also form a rare earth aluminate protective layer with the oxidation products on the material surface. This protective layer has strong chemical inertness and can effectively block the diffusion of corrosive media such as molten slag and alkaline gases into the material interior, thereby improving the corrosion resistance rate.

[0027] Furthermore, the composite antioxidant is prepared by mixing aluminum powder, silicon powder and ZrB2 powder in a mass ratio of (2-3):2:1.

[0028] By adopting the above technical solutions, the oxidation process of aluminum powder and silicon powder is accompanied by slight volume expansion, which can fill the tiny pores inside the material and reduce stress concentration; the high hardness of ZrB2 powder can enhance the high-temperature mechanical stability of the material, prevent the oxide layer from peeling off, and adapt to multi-media erosion environments.

[0029] Secondly, the present invention also provides a method for preparing the above-mentioned amorphous refractory material containing nanoparticles, comprising the following steps:

[0030] S1: Modified nano-graphite powder, nano-titanium powder, nano-ZrO2-Y2O3, rare earth composite stabilizer, composite antioxidant and part of silica sol are mixed and dispersed at high speed to obtain mixture 1;

[0031] S2: Mix the aluminate coupling agent with the remaining silica sol evenly to obtain mixture 2;

[0032] S3: Mix mixture 1, mixture 2, alumina micro powder, silicon carbide micro powder, modified carbon fiber and short-cut mullite fiber, stir, cure at 30-60℃ for 12-24h, and then dry at 100-120℃ for 24-48h.

[0033] By adopting the above technical solution, mixing is carried out in stages to avoid clumping.

[0034] Furthermore, in step S1, the high-speed dispersion speed is 3000-5000 rpm, and the dispersion time is 20-40 min.

[0035] By adopting the above technical solution, a high rotation speed of 3000-5000 rpm can generate strong shear force, effectively breaking the initial agglomerates of modified nano-graphite powder, nano-titanium powder, nano-ZrO2-Y2O3, etc.

[0036] In summary, the beneficial effects of this invention are:

[0037] 1. This invention improves the dispersion stability of nano-graphite powder in refractory material systems by grafting and modifying it with a silane coupling agent; at the same time, it introduces an aluminate coupling agent to further improve the agglomeration problem between powders; on the other hand, the preparation method adopts a stepwise dispersion process, which avoids the problems of loose structure and easy penetration of corrosive media caused by carbon agglomeration.

[0038] 2. This invention modifies carbon fiber to give it a ceramic coating, which has the properties of anti-oxidation, anti-corrosion, and wear resistance. The rare earth aluminate protective layer formed by the rare earth composite stabilizer blocks the penetration of alkaline gas and slag. It works synergistically with the composite antioxidant and nanoparticles in the refractory material system to further improve the overall anti-oxidation and anti-corrosion properties of the material.

[0039] 3. At the nanoscale, the phase transformation toughening effect of nano-ZrO2-Y2O3 in the refractory material system absorbs thermal stress, and rare earth composite stabilizers inhibit grain growth. At the fiber level, the coated modified carbon fiber and short-cut mullite fiber hinder crack propagation and alleviate internal stress caused by thermal expansion and contraction. They synergistically improve the thermal shock resistance of the material and can be stably adapted to frequent temperature rise and fall scenarios such as cement rotary kilns and steel blast furnaces. Attached Figure Description

[0040] Figure 1 SEM images of unmodified carbon fibers in unshaped refractories;

[0041] Figure 2 This is a SEM image of modified carbon fiber in unshaped refractories. Detailed Implementation

[0042] The technical solution of the present invention will be explained in detail below with reference to several representative embodiments.

[0043] Unless otherwise specified, the experimental methods used in the following examples and comparative examples are conventional methods. Unless otherwise specified, the materials and reagents used in the following examples and comparative examples are commercially available.

[0044] Lanthanum oxide: particle size ≤ 5 μm, purity ≥ 99%;

[0045] Zirconia: Particle size ≤ 5 μm, purity ≥ 99.5%;

[0046] Aluminum powder: particle size 5-10μm, purity ≥99%;

[0047] Silica powder: particle size 5-10μm, purity ≥99%;

[0048] ZrB2 powder: particle size 10-20μm, purity ≥98%;

[0049] Nano ZrO2-Y2O3: Particle size 30-50nm, purity ≥99.5%;

[0050] Nano titanium powder: particle size 30-50nm, purity ≥99%;

[0051] Short-cut mullite fibers: 3-5 mm in length, 10-20 μm in diameter;

[0052] Silica sol: SiO2 content is 35%.

[0053] Preparation example: Preparation of modified nano-graphite powder

[0054] Preparation Example 1

[0055] The particle size of the nano-graphite powder used in the following preparation examples is 100 nm.

[0056] This preparation example provides a method for preparing modified nano-graphite powder, the specific steps of which are as follows:

[0057] 100g of nano-graphite powder, 8g of silane coupling agent KH550, 1200mL of anhydrous ethanol and 120mL of water were mixed and stirred for 5min to obtain a suspension. The suspension was transferred to the reaction tank of an ultrasonic disperser, and the constant temperature water bath was turned on to control the system temperature at 35℃, the ultrasonic power at 500W and the frequency at 30kHz, and ultrasonic dispersion was carried out for 1h. After ultrasonic dispersion, the mixture was transferred to a high-speed centrifuge and centrifuged at 8000r / min for 10min. The mixture was then transferred to a vacuum drying oven and dried at 80℃ for 8h to obtain modified nano-graphite powder.

[0058] Preparation Example 2

[0059] This preparation example provides a method for preparing modified nano-graphite powder, the specific steps of which are as follows:

[0060] Mix 100g of nano-graphite powder, 9g of silane coupling agent KH550, 800mL of anhydrous ethanol and 100mL of water, and stir for 5min to obtain a suspension. Transfer the suspension to the reaction tank of an ultrasonic disperser, turn on the constant temperature water bath, control the system temperature at 35℃, ultrasonic power at 500W and frequency at 30kHz, and ultrasonically disperse for 1h. After ultrasonic dispersion, transfer to a high-speed centrifuge, centrifuge at 8000r / min for 10min, and transfer to a vacuum drying oven to dry at 80℃ for 8h to obtain modified nano-graphite powder.

[0061] Preparation Example 3

[0062] This preparation example provides a method for preparing modified nano-graphite powder, the specific steps of which are as follows:

[0063] 100g of nano-graphite powder, 12g of silane coupling agent KH550, 1100mL of anhydrous ethanol and 120mL of water were mixed and stirred for 5min to obtain a suspension. The suspension was transferred to the reaction tank of an ultrasonic disperser, and the constant temperature water bath was turned on to control the system temperature at 35℃, the ultrasonic power at 500W and the frequency at 30kHz, and ultrasonic dispersion was carried out for 1h. After ultrasonic dispersion, the mixture was transferred to a high-speed centrifuge and centrifuged at 8000r / min for 10min. The mixture was then transferred to a vacuum drying oven and dried at 80℃ for 8h to obtain modified nano-graphite powder.

[0064] Preparation examples, preparation of modified carbon fibers

[0065] The octaaminophenyl-POSS and carbon fibers used in the following preparation examples were both pretreated, and the specific steps are as follows:

[0066] 1. The octaaminophenyl-POSS was dried under vacuum at 60°C for 5 hours to obtain the dried octaaminophenyl-POSS;

[0067] 2. Place the carbon fiber in a tube furnace and heat it to 450℃ for 4 hours under a nitrogen atmosphere at a heating rate of 5℃ / min. Then, let it cool naturally to room temperature. After that, soak it in 65% concentrated nitric acid for 30 minutes, wash it 4 times with deionized water, and dry it in a vacuum drying oven at 80℃ for 8 hours to obtain acid-treated carbon fiber.

[0068] Preparation Example 4

[0069] This preparation example provides a method for preparing modified carbon fiber, the specific steps of which are as follows:

[0070] (1) Add 50g of dried octaaminophenyl-POSS and 400g of epoxy-terminated borosilicate prepolymer to a high-speed disperser and stir for 1h. Transfer to a vacuum drying oven and degas for 30min under -0.09MPa. Pour the degassed mixture into a mold and gradually heat to 85℃ for 1.5h. Gradually heat to 135℃ for 4h and cool naturally to obtain POSS-borosilicate hybrid material.

[0071] (2) Mix 20g of POSS-borosilicate hybrid material with 160mL of toluene, ultrasonically disperse for 30min, add anhydrous ethanol to the solution, stir for 10min, and control the solution viscosity to 0.02Pa using a rotational viscometer. After being left at room temperature for 24 hours, a toluene solution of POSS-borosilicate hybrid material was obtained.

[0072] (3) Add 300g of acid-treated carbon fiber to a toluene solution of POSS-borosilicate hybrid material, seal and impregnate for 1.5h, slowly lift the carbon fiber at a rate of 5mm / s, drain off excess solution, suspend the carbon fiber in a fume hood and allow it to evaporate naturally for 6h; transfer it to a tube furnace, and in a mixed atmosphere of nitrogen and 5% argon, heat it to 85℃ at a heating rate of 1.5℃ / min and react for 10h, heat it to 245℃ at a heating rate of 3.5℃ / min and react for 7.5h, heat it to 1500℃ at a heating rate of 5℃ / min and react for 2h, and cool it naturally to obtain modified carbon fiber.

[0073] Figure 1 The image shows an SEM image of unmodified carbon fibers in unshaped refractory materials, which reveals agglomeration and uneven dispersion of the carbon fibers. Figure 2 SEM images of modified carbon fibers in unshaped refractories, and... Figure 1 In comparison, modified carbon fiber exhibits improved dispersibility and exhibits no large-area agglomeration.

[0074] Preparation Example 5

[0075] This preparation example provides a method for preparing modified carbon fiber, the specific steps of which are as follows:

[0076] (1) Add 50g of dried octaaminophenyl-POSS and 500g of epoxy-terminated borosilicate prepolymer to a high-speed disperser and stir for 1h. Transfer to a vacuum drying oven and degas for 30min under -0.09MPa conditions. Pour the degassed mixture into a mold and gradually heat to 100℃ for 1h. Gradually heat to 150℃ for 3h and cool naturally to obtain POSS-borosilicate hybrid material.

[0077] (2) Mix 20g of POSS-borosilicate hybrid material with 180mL of toluene, ultrasonically disperse for 30min, add anhydrous ethanol to the solution, stir for 10min, and control the solution viscosity to 0.02Pa using a rotational viscometer. After being left at room temperature for 24 hours, a toluene solution of POSS-borosilicate hybrid material was obtained.

[0078] (3) Add 400g of acid-treated carbon fiber to a toluene solution of POSS-borosilicate hybrid material, seal and impregnate for 1.5h, slowly lift the carbon fiber at a rate of 5mm / s, drain off the excess solution, suspend the carbon fiber in a fume hood and allow it to evaporate naturally for 4h; transfer it to a tube furnace, and in a mixed atmosphere of nitrogen and 5% argon, heat it to 90℃ at a heating rate of 2℃ / min and react for 10h, heat it to 240℃ at a heating rate of 3℃ / min and react for 7h, heat it to 1550℃ at a heating rate of 4℃ / min and react for 2.5h, and allow it to cool naturally to obtain modified carbon fiber.

[0079] Preparation Example 6

[0080] This preparation example provides a method for preparing modified carbon fiber, the specific steps of which are as follows:

[0081] (1) Add 50g of dried octaaminophenyl-POSS and 600g of epoxy-terminated borosilicate prepolymer to a high-speed disperser and stir for 1h. Transfer to a vacuum drying oven and degas for 30min under -0.09MPa. Pour the degassed mixture into a mold and gradually heat to 80℃ for 2h. Gradually heat to 120℃ for 4.5h and cool naturally to obtain POSS-borosilicate hybrid material.

[0082] (2) Mix 20g of POSS-borosilicate hybrid material with 200mL of toluene, sonicate for 30min, add anhydrous ethanol to the solution, stir for 10min, and control the solution viscosity to 0.02Pa using a rotational viscometer. After being left at room temperature for 24 hours, a toluene solution of POSS-borosilicate hybrid material was obtained.

[0083] (3) Add 380g of acid-treated carbon fiber to a toluene solution of POSS-borosilicate hybrid material, seal and impregnate for 1.5h, slowly lift the carbon fiber at a rate of 5mm / s, drain off excess solution, suspend the carbon fiber in a fume hood and allow it to evaporate naturally for 4h; transfer it to a tube furnace, and in a mixed atmosphere of nitrogen and 5% argon, heat it to 90℃ at a heating rate of 2℃ / min and react for 9h, heat it to 250℃ at a heating rate of 4℃ / min and react for 8h, heat it to 1500℃ at a heating rate of 4℃ / min and react for 3h, and allow it to cool naturally to obtain modified carbon fiber.

[0084] Preparation Example 7

[0085] The difference from Preparation Example 4 is that the amount of acid-treated carbon fiber used is 350g.

[0086] Preparation Example 8

[0087] The difference from Preparation Example 4 is that the amount of epoxy-terminated borosilicate prepolymer used is 450g.

[0088] Example 1

[0089] This embodiment provides an amorphous refractory material containing nanoparticles, which is composed of the following components by mass:

[0090] Alumina micro powder (particle size 35μm): 60 parts;

[0091] Silicon carbide micro powder (particle size 75μm): 30 parts;

[0092] Preparation Example 1: 1 part of modified nano-graphite powder;

[0093] Silica sol: 5 parts;

[0094] Aluminate coupling agent: 3 parts;

[0095] Modified carbon fiber prepared in Example 4: 4 parts;

[0096] Short-cut mullite fibers: 2 parts;

[0097] Rare earth composite stabilizer: 2 parts;

[0098] Nano titanium powder: 1 part;

[0099] Nano ZrO2-Y2O3: 3 parts;

[0100] Compound antioxidant: 2 parts;

[0101] The rare earth composite stabilizer is a mixture of lanthanum oxide and yttrium oxide in a mass ratio of 1:2;

[0102] The composite antioxidant is a mixture of aluminum powder, silicon powder and ZrB2 powder in a mass ratio of 2:2:1.

[0103] This embodiment provides a method for preparing an amorphous refractory material containing nanoparticles, the specific steps of which are as follows:

[0104] S1: Mix all the modified nano-graphite powder, nano-titanium powder, nano-ZrO2-Y2O3, rare earth composite stabilizer, composite antioxidant and 1 / 2 of the amount of silica sol, and disperse at high speed at 3000 rpm for 20 min to obtain mixture 1;

[0105] S2: Mix the aluminate coupling agent with the remaining 1 / 2 of the silica sol and stir manually until homogeneous to obtain mixture 2;

[0106] S3: Add alumina micro powder and silicon carbide micro powder to a planetary mixer, pour in mixture 2, stir for 5 minutes, then add mixture 1, continue stirring for 10 minutes, finally add modified carbon fiber and short-cut mullite fiber, gently stir for 5 minutes until the fiber is evenly dispersed, place in an environment of 60℃ and humidity >95% for 12 hours, then transfer to a forced-air drying oven at 120℃ for 24 hours to obtain an amorphous refractory material containing nanoparticles.

[0107] Example 2

[0108] This embodiment provides an amorphous refractory material containing nanoparticles, which is composed of the following components by mass:

[0109] Alumina micro powder (particle size 25μm): 65 parts;

[0110] Silicon carbide micro powder (particle size 45μm): 25 parts;

[0111] Modified nano-graphite powder prepared in Example 3: 3 parts;

[0112] Silica sol: 6 parts;

[0113] Aluminate coupling agent: 4 parts;

[0114] Modified carbon fiber prepared in Example 5: 5 parts;

[0115] Short-cut mullite fibers: 3 parts;

[0116] Rare earth composite stabilizer: 2.5 parts;

[0117] Nano titanium powder: 1.5 parts;

[0118] Nano ZrO2-Y2O3: 3 parts;

[0119] Compound antioxidant: 3 parts;

[0120] The rare earth composite stabilizer is a mixture of lanthanum oxide and yttrium oxide in a mass ratio of 1:2;

[0121] The composite antioxidant is a mixture of aluminum powder, silicon powder and ZrB2 powder in a mass ratio of 2.5:2:1.

[0122] This embodiment provides a method for preparing an amorphous refractory material containing nanoparticles, the specific steps of which are as follows:

[0123] S1: Mix all the modified nano-graphite powder, nano-titanium powder, nano-ZrO2-Y2O3, rare earth composite stabilizer, composite antioxidant and 1 / 2 of the amount of silica sol, and disperse at high speed at 4000 rpm for 30 min to obtain mixture 1;

[0124] S2: Mix the aluminate coupling agent with the remaining 1 / 2 of the silica sol and stir manually until homogeneous to obtain mixture 2;

[0125] S3: Add alumina micro powder and silicon carbide micro powder to a planetary mixer, pour in mixture 2, stir for 5 minutes, then add mixture 1, continue stirring for 10 minutes, finally add modified carbon fiber and short-cut mullite fiber, gently stir for 5 minutes until the fiber is evenly dispersed, place in an environment of 35℃ and humidity >95% for 24 hours, then transfer to a 120℃ forced-air drying oven for 36 hours to obtain an amorphous refractory material containing nanoparticles.

[0126] Example 3

[0127] This embodiment provides an amorphous refractory material containing nanoparticles, which is composed of the following components by mass:

[0128] Alumina micro powder (particle size 10μm): 68 parts;

[0129] Silicon carbide micro powder (particle size 20μm): 22 parts;

[0130] Modified nano-graphite powder prepared in Example 2: 5 parts;

[0131] Silica sol: 7 parts;

[0132] Aluminate coupling agent: 5 parts;

[0133] Modified carbon fiber prepared in Example 4: 6 parts;

[0134] Short-cut mullite fibers: 4 parts;

[0135] Rare earth composite stabilizer: 3 parts;

[0136] Nano titanium powder: 2 parts;

[0137] Nano ZrO2-Y2O3: 5 parts;

[0138] Compound antioxidant: 4 parts;

[0139] The rare earth composite stabilizer is a mixture of lanthanum oxide and yttrium oxide in a mass ratio of 1:2;

[0140] The composite antioxidant is a mixture of aluminum powder, silicon powder and ZrB2 powder in a mass ratio of 2:2:1.

[0141] This embodiment provides a method for preparing an amorphous refractory material containing nanoparticles, the specific steps of which are as follows:

[0142] S1: Mix all the modified nano-graphite powder, nano-titanium powder, nano-ZrO2-Y2O3, rare earth composite stabilizer, composite antioxidant and 1 / 2 of the amount of silica sol, and disperse at high speed at 4500 rpm for 40 min to obtain mixture 1;

[0143] S2: Mix the aluminate coupling agent with the remaining 1 / 2 of the silica sol and stir manually until homogeneous to obtain mixture 2;

[0144] S3: Add alumina micro powder and silicon carbide micro powder to a planetary mixer, pour in mixture 2, stir for 5 minutes, then add mixture 1, continue stirring for 10 minutes, finally add modified carbon fiber and short-cut mullite fiber, gently stir for 5 minutes until the fiber is evenly dispersed, place in an environment of 40℃ and humidity >95% for 24 hours, then transfer to a 100℃ forced-air drying oven for 48 hours to obtain an amorphous refractory material containing nanoparticles.

[0145] Example 4

[0146] This embodiment provides an amorphous refractory material containing nanoparticles, which is composed of the following components by mass:

[0147] Alumina micro powder (particle size 30μm): 62 parts;

[0148] Silicon carbide micro powder (particle size 50μm): 28 parts;

[0149] Modified nano-graphite powder prepared in Example 3: 2 parts;

[0150] Silica sol: 5.5 parts;

[0151] Aluminate coupling agent: 3.5 parts;

[0152] Modified carbon fiber prepared in Example 6: 7 parts;

[0153] Short-cut mullite fibers: 5 parts;

[0154] Rare earth composite stabilizer: 2.2 parts;

[0155] Nano titanium powder: 1.2 parts;

[0156] Nano ZrO2-Y2O3: 3.5 parts;

[0157] Compound antioxidant: 2.5 parts;

[0158] The rare earth composite stabilizer is a mixture of lanthanum oxide and yttrium oxide in a mass ratio of 1:3;

[0159] The composite antioxidant is a mixture of aluminum powder, silicon powder and ZrB2 powder in a mass ratio of 3:2:1.

[0160] This embodiment provides a method for preparing an amorphous refractory material containing nanoparticles, the specific steps of which are as follows:

[0161] S1: Mix all the modified nano-graphite powder, nano-titanium powder, nano-ZrO2-Y2O3, rare earth composite stabilizer, composite antioxidant and 1 / 2 of the amount of silica sol, and disperse at high speed at 5000 rpm for 25 min to obtain mixture 1;

[0162] S2: Mix the aluminate coupling agent with the remaining 1 / 2 of the silica sol and stir manually until homogeneous to obtain mixture 2;

[0163] S3: Add alumina micro powder and silicon carbide micro powder to a planetary mixer, pour in mixture 2, stir for 5 minutes, then add mixture 1, continue stirring for 10 minutes, finally add modified carbon fiber and short-cut mullite fiber, gently stir for 5 minutes until the fiber is evenly dispersed, place in an environment of 40℃ and humidity >95% for 12 hours, then transfer to a 100℃ forced-air drying oven for 24 hours to obtain an amorphous refractory material containing nanoparticles.

[0164] Example 5

[0165] This embodiment provides an amorphous refractory material containing nanoparticles, which is composed of the following components by mass:

[0166] Alumina micro powder (particle size 15μm): 70 parts;

[0167] Silicon carbide micro powder (particle size 30μm): 20 parts;

[0168] Modified nano-graphite powder prepared in Example 3: 4 parts;

[0169] Silica sol: 6.5 parts;

[0170] Aluminate coupling agent: 4.5 parts;

[0171] Preparation Example 8: 4.5 parts of modified carbon fiber;

[0172] Short-cut mullite fibers: 2.5 parts;

[0173] Rare earth composite stabilizer: 2.8 parts;

[0174] Nano titanium powder: 1.8 parts;

[0175] Nano ZrO2-Y2O3: 4.5 parts;

[0176] Compound antioxidant: 4 parts;

[0177] The rare earth composite stabilizer is a mixture of lanthanum oxide and yttrium oxide in a mass ratio of 1:3;

[0178] The composite antioxidant is a mixture of aluminum powder, silicon powder and ZrB2 powder in a mass ratio of 3:2:1.

[0179] This embodiment provides a method for preparing an amorphous refractory material containing nanoparticles, the specific steps of which are as follows:

[0180] S1: Mix all the modified nano-graphite powder, nano-titanium powder, nano-ZrO2-Y2O3, rare earth composite stabilizer, composite antioxidant and 1 / 2 of the amount of silica sol, and disperse at high speed at 5000 rpm for 35 min to obtain mixture 1;

[0181] S2: Mix the aluminate coupling agent with the remaining 1 / 2 of the silica sol and stir manually until homogeneous to obtain mixture 2;

[0182] S3: Add alumina micro powder and silicon carbide micro powder to a planetary mixer, pour in mixture 2, stir for 5 minutes, then add mixture 1, continue stirring for 10 minutes, finally add modified carbon fiber and short-cut mullite fiber, gently stir for 5 minutes until the fiber is evenly dispersed, place in an environment of 30℃ and humidity >95% for 20 hours, then transfer to a forced-air drying oven at 120℃ for 48 hours to obtain an amorphous refractory material containing nanoparticles.

[0183] Comparative Example 1

[0184] The difference from Example 3 is that this comparative example uses unmodified nano-graphite powder and unmodified carbon fiber.

[0185] Comparative Example 2

[0186] The difference from Example 3 is that no composite antioxidant was added in this comparative example.

[0187] Comparative Example 3

[0188] The difference from Example 3 is that this comparative example does not contain modified carbon fiber and short-cut mullite fiber.

[0189] Comparative Example 4

[0190] The difference from Example 3 is that this comparative example does not add nano ZrO2-Y2O3 or nano titanium powder.

[0191] Related performance tests

[0192] The amorphous refractory materials prepared in Examples 1-5 and Comparative Examples 1-4 were subjected to relevant performance tests, and the test results are shown in Table 1.

[0193] Table 1 Test Results

[0194]

[0195] The unshaped refractory material prepared by this invention has excellent thermal shock resistance, oxidation resistance and other properties.

[0196] The technical solutions of the present invention have been described above by way of example. It should be noted that, without departing from the core concept of the present invention, any simple modifications, alterations or equivalent substitutions made by those skilled in the art are within the protection scope of the present invention.

Claims

1. An amorphous refractory material containing nanoparticles, characterized in that, It consists of the following components in parts by mass: 60-70 parts alumina micro powder, 20-30 parts silicon carbide micro powder, 1-5 parts modified nano-graphite powder, 5-7 parts silica sol, 3-5 parts aluminate coupling agent, 4-7 parts modified carbon fiber, 2-5 parts short-cut mullite fiber, 2-3 parts rare earth composite stabilizer, 1-2 parts nano titanium powder, 3-5 parts nano ZrO2-Y2O3, and 2-4 parts composite antioxidant; The alumina micro powder has a particle size of 5-50 μm, and the silicon carbide micro powder has a particle size of 10-80 μm; The method for preparing the modified carbon fiber includes the following steps: (1) Mixing octaaminophenyl-POSS with epoxy-terminated borosilicate prepolymer evenly, degassing under vacuum, heating to 80-100℃ for 1-2 hours, and continuing to heat to 120-150℃ for 3-5 hours for curing to obtain POSS-borosilicate hybrid material; (2) Mixing POSS-borosilicate hybrid material with toluene at a mass-volume ratio of 1g:8-10mL evenly to obtain POSS-borosilicate hybrid material toluene solution; (3) Immersing the carbon fiber in the POSS-borosilicate hybrid material toluene solution, immersing at a constant temperature, removing and drying, placing it under a gradient heating reaction in a nitrogen and argon mixed atmosphere, and cooling to room temperature to obtain modified carbon fiber; The rare earth composite stabilizer is prepared by mixing lanthanum oxide and yttrium oxide in a mass ratio of 1:(2-3).

2. The amorphous refractory material containing nanoparticles according to claim 1, characterized in that, The preparation method of the modified nano-graphite powder includes the following steps: Nano-graphite powder, silane coupling agent, anhydrous ethanol and water are mixed in a mass-volume ratio of 10g:0.7-1.2g:80-120mL:10-12mL, ultrasonically dispersed, centrifuged and dried to obtain modified nano-graphite powder.

3. The amorphous refractory material containing nanoparticles according to claim 1, characterized in that, In step (1), the mass ratio of octaaminophenyl-POSS to epoxy-terminated borosilicate prepolymer is 1:(8-12).

4. The amorphous refractory material containing nanoparticles according to claim 1, characterized in that, In step (3), the mass ratio of carbon fiber to toluene in POSS-borosilicate hybrid material is (15-20):

1.

5. The amorphous refractory material containing nanoparticles according to claim 1, characterized in that, In step (3), the heating reaction steps are as follows: heating to 80-90℃ at a heating rate of 1-2℃ / min and reacting for 9-10h, heating to 240-250℃ at a heating rate of 3-4℃ / min and reacting for 7-8h, and heating to 1500-1550℃ at a heating rate of 4-5℃ / min and reacting for 2-3h.

6. The amorphous refractory material containing nanoparticles according to claim 1, characterized in that, The composite antioxidant is prepared by mixing aluminum powder, silicon powder and ZrB2 powder in a mass ratio of (2-3):2:

1.

7. A method for preparing an amorphous refractory material containing nanoparticles according to any one of claims 1-6, characterized in that, Includes the following steps: S1: Modified nano-graphite powder, nano-titanium powder, nano-ZrO2-Y2O3, rare earth composite stabilizer, composite antioxidant and part of silica sol are mixed and dispersed at high speed to obtain mixture 1; S2: Mix the aluminate coupling agent with the remaining silica sol evenly to obtain mixture 2; S3: Mix mixture 1, mixture 2, alumina micro powder, silicon carbide micro powder, modified carbon fiber and short-cut mullite fiber, stir, cure at 30-60℃ for 12-24h, and then dry at 100-120℃ for 24-48h.

8. The method for preparing an amorphous refractory material containing nanoparticles according to claim 7, characterized in that, In step S1, the high-speed dispersion speed is 3000-5000 rpm, and the dispersion time is 20-40 min.

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