WO2024011720A1 - Unfired silicon carbide-magnesium aluminate spinel refractory material and preparation method therefor, and product - Google Patents

Abstract

Disclosed in the present invention are an unfired silicon carbide-magnesium aluminate spinel refractory material and a preparation method therefor, and a product, which belong to the technical field of refractory materials. The raw materials of the refractory material disclosed in the present invention comprise a solid powder and a liquid binding agent, wherein the solid powder comprises silicon carbide particles, a fine magnesium aluminate spinel powder, a metal aluminum powder and a solid additive, the metal aluminum powder being formed by coating metal aluminum particles with an organic polymer, and the solid additive being selected from one or more of calcium aluminate cement, boric oxide and phosphorus pentoxide. In the present invention, the silicon carbide-magnesium aluminate spinel refractory material with good fire resistance and slag resistance can be obtained simply by means of a low-temperature treatment at about 200°C without high-temperature firing, because a series of changes come up in the components in the refractory material, and these changes result in the improved strength, stable volume and improved slag resistance of the material and effectively reduce the fuel waste caused by the high-temperature firing of the silicon carbide-magnesium aluminate spinel composite refractory material in the prior art.

Description

Burn-free silicon carbide-magnesium aluminum spinel refractory material and its preparation method and products

This application claims the priority of the Chinese patent application submitted to the China Patent Office on July 11, 2022, with the application number 2022108154089 and the invention name "Burn-Free Silicon Carbide-Magnesia Aluminum Spinel Refractory Material and Preparation Method and Products", The entire contents of this application are incorporated herein by reference.

Technical field

The invention belongs to the technical field of refractory materials, and in particular relates to a burn-free silicon carbide-magnesia aluminum spinel refractory material and its preparation method and products.

Background technique

High-chromium refractory materials have excellent resistance to slag erosion and are commonly used as lining materials for highly corrosive media and high-temperature vessels such as coal-water slurry coal gasification furnaces. However, they have the potential harm of hexavalent chromium to the human body and the environment, and are urgently needed. Green refractory alternatives.

Silicon carbide-magnesia-aluminum spinel composite refractory material is a potential green chromium-free refractory material that can meet the requirements of high temperature and slag resistance. ZL201711187027.6 discloses a silicon carbide-magnesia-aluminum spinel composite refractory material. The silicon carbide-magnesia-aluminum spinel composite refractory material uses silicon carbide particles as aggregates and uses magnesia-aluminum spinel, alumina, and oxide. Magnesium fine powder or micro powder is used as the matrix, and antioxidants are added; the aggregate, matrix and binding agent are mixed and formed, and then dried and fired under the protection of charcoal or nitrogen atmosphere. The maximum firing temperature is 1450~1600℃ , a composite refractory material with SiC as the main crystal phase and magnesia-aluminum spinel as the sub-crystalline phase is obtained; the sum of the mass fractions of SiC, MgO and Al ₂ O ₃ in the composite refractory material is greater than or equal to 96.6%, of which the mass of SiC The mass fraction is 58.5% to 83.5%, the mass fraction of Al ₂ O ₃ is 10% to 28.5%, the mass fraction of MgO is 2.5% to 11%, the apparent porosity is 15% to 19%, and the volume density is 2.57 to 2.85g/cm ³ .

In order to further improve the high-temperature mechanical strength of silicon carbide-magnesium aluminum spinel composite refractory materials, ZL202010646418.5 discloses a silicon carbide-magnesia aluminum spinel-aluminum composite refractory material, which is mainly based on ZL201711187027.6. Metal aluminum powder coated with aluminum sol is added to the matrix with a particle size range of 10 μm to 45 μm, accounting for 2% to 8% of the total mass of the raw materials. After machine pressing, the green body is fired at high temperature. It mainly uses metal aluminum powder in a carbon-buried atmosphere. When fired at the maximum temperature of 1500°C to 1600°C, the Al-O-N-C fiber reinforcement phase is formed internally, which improves the normal and high-temperature mechanical properties of silicon carbide-magnesium aluminum spinel composite refractory materials.

ZL202010809854. powder, using the "two-step three-stage thermal insulation firing method": that is, in the first step, the Al and Si powder are nitrided at 1150°C ~ 1250°C, and the nitrided Al and Si powder are combined with silicon carbide particles and magnesium aluminum The fine spinel powder is mixed with a binding agent and then formed into a green body. In the second step, the three-stage heat preservation is carried out and nitrided and fired at a maximum temperature of 1300°C to 1600°C. Its main purpose is to form a metal-based sialon phase such as Mg-α-Sialon phase between silicon carbide particles and spinel powder when adding Al and Si powder and performing nitriding treatment to improve mechanical strength and slag resistance.

The above three methods all use high-temperature firing processes in carbon burial or nitriding atmospheres to prepare silicon carbide-magnesia-aluminum spinel composite refractory materials. The firing process is complex, the firing temperature is high, fuel consumption is large, and the cost is high.

In high-temperature devices such as coal-water slurry gasifiers, the air flow, slag and pulverized coal in the furnace seriously erode the refractory materials, which requires high mechanical strength of the refractory materials. Moreover, the gasifier is a high-pressure sealed device, and the vertical height of the furnace lining in the furnace is 10 meters or above, the structural stability of refractory bricks is required to be high. Refractory materials are required to have certain mechanical strength and structural stability from normal temperature ovens to continuous high-temperature operations of 1300 to 1500°C. Therefore, if refractory materials can not only have the above properties but also reduce energy consumption, they will definitely be able to save costs, improve economic benefits, and alleviate the energy crisis.

The information disclosed in this Background section is merely intended to enhance an understanding of the general background of the invention and should not be construed as an admission or in any way implying that the information constitutes prior art that is already known to a person of ordinary skill in the art.

Contents of the invention

The purpose of the present invention is to solve the technical problems of complex refractory preparation methods, high energy consumption and high cost in the existing technology, and to provide a burn-free silicon carbide-magnesia aluminum spinel refractory material and its preparation method and products.

A first aspect of the present invention provides a burn-free silicon carbide-magnesia-aluminum spinel refractory material. The burn-free silicon carbide-magnesia-aluminum spinel refractory material has SiC as the main crystal phase and magnesia-aluminum spinel as the secondary crystal. phase; preferably, the above-mentioned secondary crystalline phase fills the gaps in the above-mentioned main crystalline phase;

And/or, the apparent porosity of the above-mentioned unburned silicon carbide-magnesium aluminum spinel refractory material is 5% to 12%;

And/or, the bulk density of the above-mentioned burn-free silicon carbide-magnesium aluminum spinel refractory material is 2.65~2.90g/cm ³ ;

And/or, the room temperature flexural strength of the above-mentioned unburned silicon carbide-magnesium aluminum spinel refractory material is 25~40MPa;

And/or, the 800°C high temperature flexural strength of the above-mentioned burn-free silicon carbide-magnesium aluminum spinel refractory material is 15~30MPa;

And/or, the 1400°C high temperature flexural strength of the above-mentioned burn-free silicon carbide-magnesium aluminum spinel refractory material is 25-40MPa.

In some embodiments, the above-mentioned free-burning silicon carbide-magnesium aluminum spinel refractory material includes SiC, Al ₂ O ₃ and MgO; preferably, the total mass fraction of the above-mentioned SiC, Al ₂ O ₃ and MgO is ≥95%; more Preferably, the mass fraction of SiC is 53% to 75%, the mass fraction of Al ₂ O ₃ is 18% to 35%, and the mass fraction of MgO is 5% to 10%.

In some embodiments, the raw materials of the above-mentioned burn-free silicon carbide-magnesium aluminum spinel refractory material include solid powder and liquid binder. The solid powder includes silicon carbide particles, magnesium aluminum spinel fine powder, metal aluminum powder and solid additive.

In some embodiments, each raw material of the above-mentioned burn-free silicon carbide-magnesium aluminum spinel refractory material includes, in parts by weight:

55 to 75 parts of silicon carbide particles;

20 to 40 parts of magnesia-aluminum spinel fine powder;

2 to 5 parts of metal aluminum powder;

1 to 5 parts of solid additives;

The added amount of liquid binding agent is 4% to 7% of the total mass of the above-mentioned solid powder.

In some embodiments, the silicon carbide particles are fused silicon carbide particles;

And/or, the above-mentioned magnesium-aluminum spinel fine powder is sintered or fused magnesium-aluminum spinel fine powder;

And/or, the above-mentioned metal aluminum powder is an organic coating coated on the metal aluminum particles;

And/or, the above-mentioned solid additive is selected from one or more types of calcium aluminate cement, boron oxide, and phosphorus pentoxide; preferably, the above-mentioned calcium aluminate cement contains alumina-magnesium spinel;

And/or, the above-mentioned binding agent is a polymer with thermosetting properties; preferably, the above-mentioned binding agent is a phenolic resin.

In some embodiments, the above-mentioned metal aluminum powder has a core-shell structure, the above-mentioned metal aluminum is the core, and the above-mentioned organic coating is the shell; preferably, the thickness of the above-mentioned organic coating is 1 to 10 μm; more preferably, the above-mentioned organic coating is The covering is selected from one or more types of polyamide, polycarbonate, polyethylene terephthalate, polybutylene terephthalate, and polyethersulfone resin.

A second aspect of the present invention provides a method for preparing burn-free silicon carbide-magnesium aluminum spinel refractory material, which includes the following steps:

Mix silicon carbide particles, aluminum magnesium spinel fine powder, metal aluminum powder, solid additives and binding agents evenly, and then press and shape the green body;

After the above green body is dried at low temperature, the above-mentioned unburned silicon carbide-magnesium aluminum spinel refractory material is obtained.

In some embodiments, the preparation method of the above-mentioned metal aluminum powder includes: mixing metal aluminum ions into a liquid organic polymer under an inert atmosphere, and then solidifying and separating to obtain organic-coated metal aluminum powder; preferably, the above-mentioned The particle size of metallic aluminum particles is 0.03~0.07mm.

In some embodiments, the silicon carbide particles are fused silicon carbide particles;

And/or, the above-mentioned magnesium-aluminum spinel fine powder is sintered or fused magnesium-aluminum spinel fine powder;

And/or, the above-mentioned solid additive is selected from one or more types of calcium aluminate cement, boron oxide, and phosphorus pentoxide; preferably, the above-mentioned calcium aluminate cement contains alumina-magnesium spinel;

And/or, the above-mentioned binding agent is a polymer with thermosetting properties; preferably, the above-mentioned binding agent is a phenolic resin;

And/or, the temperature of the above-mentioned low-temperature drying is 150-250°C, and more preferably, the time of the above-mentioned low-temperature drying is 8-24 hours.

A third aspect of the present invention provides a refractory product, including the above-mentioned unburned silicon carbide-magnesium alumina spinel refractory material or the above-mentioned unburned silicon carbide-magnesium alumina spinel refractory material prepared by the above-mentioned preparation method.

Compared with the existing technology, the technical effects achieved by the present invention are as follows:

(1) On the premise of maintaining the basic chemical composition and mineral phase composition of the silicon carbide-magnesium aluminum spinel refractory material to meet the needs of high-temperature applications for material refractory resistance, slag resistance, etc., the present invention does not require high temperature during material preparation. Firing requires only low-temperature treatment at around 200°C. This is because during the use of the silicon carbide-magnesia aluminum spinel refractory material in the present invention, as the furnace temperature changes from low temperature to high temperature, the refractory material is also heated to the corresponding temperature, and the components in the refractory material change accordingly. A series of changes occur in the temperature. These changes lead to an increase in the strength, volume stability, and slag resistance of the material, effectively reducing the waste of fuel and energy consumption in the high-temperature firing of silicon carbide-magnesia aluminum spinel composite refractory materials in the existing technology. Shorten the preparation process and save economic costs and time costs.

(2) In the present invention, the phenolic resin provides mechanical strength from normal temperature to 600°C. The solid additive forms a liquid phase at 400-1000°C to improve the medium-temperature strength of the material. The metal aluminum powder interacts with CO and CO in the heat treatment atmosphere at 900-1500°C. O ₂ , N _2, etc. form the Al-C-N-O fiber reinforcement phase, which improves the high-temperature strength of the material. The composite addition of these components ensures that the bonding strength of the temperature-resistant material does not decay from normal temperature to high temperature, and reduces the risk of burning. Dependence on increasing material strength.

(3) Through the combination of raw material components and reasonable proportions, the green body formed by the present invention only needs low-temperature heat treatment at about 200°C. From masonry to thermal preparation, the waste heat of the oven heating process is used to achieve normal temperature to the highest use environment. High mechanical strength and volume stability achieve the purpose of energy saving and cost reduction.

Description of drawings

Figure 1 is an XRD pattern of the unburned silicon carbide-magnesium aluminum spinel refractory material prepared in Example 1 of the present invention.

Detailed ways

The technical solutions of the present invention will be described below through specific embodiments in conjunction with the accompanying drawings. It should be understood that the mention of one or more steps in the present invention does not exclude the existence of other methods and steps before and after the combination step, or that other methods and steps can be inserted between these explicitly mentioned steps. It should also be understood that these examples are merely illustrative of the invention and are not intended to limit the scope of the invention. Unless otherwise stated, the numbering of each method step is only for the purpose of identifying each method step, and does not limit the order of each method or limit the implementation scope of the present invention. Changes or adjustments in their relative relationships will not change the technical content without substantial changes. Under the conditions, it can also be regarded as the implementable scope of the present invention.

There are no specific restrictions on the sources of the raw materials and instruments used in the examples. They can be purchased in the market or prepared according to conventional methods well known to those skilled in the art.

The invention provides a burn-free silicon carbide-magnesium aluminum spinel refractory material. The raw materials of the above-mentioned burn-free silicon carbide-magnesia aluminum spinel refractory material include solid powder and liquid binder. The above-mentioned solid powder includes silicon carbide particles, magnesium Aluminum spinel fine powder, metallic aluminum powder and solid additives.

In the present invention, the raw materials of the above-mentioned burn-free silicon carbide-magnesium aluminum spinel refractory material include, in parts by weight:

55 to 75 parts of silicon carbide particles;

20 to 40 parts of magnesia-aluminum spinel fine powder;

2 to 5 parts of metal aluminum powder;

1 to 5 parts of solid additives;

The added amount of liquid binding agent is 4% to 7% of the total mass of the above-mentioned solid powder.

In the present invention, the above-mentioned silicon carbide particles are fused silicon carbide particles; preferably, the purity of the fused silicon carbide particles is ≥97%; more preferably, the particle size of the fused silicon carbide is 0.1 mm to 3 mm.

In the present invention, the above-mentioned magnesium-aluminum spinel fine powder is sintered or fused magnesium-aluminum spinel fine powder; preferably, the particle size of the magnesium-aluminum spinel is ≤0.1mm; more preferably, the magnesium-aluminum spinel fine powder The sum of the mass fractions of Al ₂ O ₃ and MgO is ≥99.0%, of which the mass fraction of Al ₂ O ₃ is 72% to 85%. The mass fraction of Al ₂ O ₃ in the stoichiometric magnesia-aluminum spinel is about 72%. On the one hand, the use of aluminum-rich spinel is conducive to the solid solution of the MgO component in the temperature-resistant material. This is due to the fact that MgO and Al ₂ O ₃ In addition to the stoichiometric MgAl ₂ O ₄ formed at a molar ratio of 1:1, it can be seen from the binary phase diagram of MgO-Al ₂ O ₃ that a spinel solid solution can be formed near the stoichiometric ratio, and there are a large number of vacancy defects in the crystal. , there are more divalent ion vacancies in aluminum-rich spinel, which is beneficial to Fe ²⁺ , Mg ²⁺ , Ni ^2+, etc. being absorbed into solid solution; on the other hand, it is beneficial to improve the resistance of temperature-resistant materials to neutral slag components. Corrosion performance, the slag has pH, in metallurgy the CaO/SiO ₂ ratio is often used to reflect the alkalinity of the slag, the higher the ratio, the greater the alkalinity, it is easy to generate calcium silicate and other substances, which is harmful to the acidic component SiO ₂ in refractory materials. The erosion is stronger. Alumina is neutral and magnesium oxide is alkaline. If the concentration of magnesium oxide in spinel is high, it will be easily corroded by acidic slag at high temperatures. On the contrary, if the concentration of alumina in spinel is high (i.e. aluminum-rich spinel), it will be more susceptible to corrosion. Resistant to chemical attack by acidic and neutral residues.

In the present invention, the above-mentioned binding agent is a polymer with thermosetting properties; preferably, the above-mentioned binding agent is a phenolic resin. Phenolic resin has good temperature resistance and flame resistance, and provides mechanical strength from normal temperature to 600°C.

In the present invention, the above-mentioned metal aluminum powder is an organic coating wrapped around the metal aluminum particles. The above-mentioned metal aluminum powder has a core-shell structure, the metal aluminum particles are the core, and the organic coating is the shell. Preferably, the particle size of the metallic aluminum particles is 0.03-0.07 mm; more preferably, the thickness of the organic coating coated on the surface of the metallic aluminum particles is 1-10 μm; further preferably, the particle size of the metallic aluminum powder is ≤0.074 mm.

Because metal aluminum powder is easy to react with water, there is a possibility that the metal aluminum will be hydrated and deteriorated when the green body is heat treated at room temperature or low temperature in a humid environment. As a result, the hydrated metal aluminum cannot generate Al-C-N-O above 900°C. The fiber-reinforced phase cannot satisfy the improvement of high-temperature strength. The metal aluminum particles are coated with organic coatings to prevent the metal aluminum from being reacted by water vapor during the drying process of the temperature-resistant material. The residue of the organic coating during high-temperature heat treatment is mainly carbon, which will not have a negative impact on the high temperature resistance and slag resistance of the temperature-resistant material. The optimal curing temperature of phenolic resin is 150-180°C. Generally, the melting point is greater than 200°C. The organic coating can keep the organic film from being damaged during drying and protect the metal aluminum particles from hydration and oxidation.

In the present invention, the organic coating is selected from one or more types of polyamide, polycarbonate, polyethylene terephthalate, polybutylene terephthalate, and polyethersulfone resin, and has a high melting point. at a dry temperature.

In the present invention, the above-mentioned solid additive is selected from one or more types of calcium aluminate cement, boron oxide, and phosphorus pentoxide; preferably, the particle size of the above-mentioned solid additive is ≤ 200 μm; more preferably, the purity of the above-mentioned solid additive is ≥ 99%.

In the present invention, the above-mentioned calcium aluminate cement contains alumina-magnesium spinel; preferably, the sum of the mass fractions of Al ₂ O ₃ , CaO and MgO in the calcium aluminate cement is greater than or equal to 99.0%, of which Al ₂ O ₃ is 69 %~71%,

MgO is 16% to 22%, and the mineral composition of alumina-magnesium spinel is greater than or equal to 65%. After calcium aluminate cement is hydrated, it will increase the medium temperature (400-1000°C) strength of the heat-resistant material; the magnesium-aluminum spinel component in the cement will improve the slag resistance of the heat-resistant material; in addition, due to Al ₂ O ₃ , CaO The substance formed with MgO has a higher melting point, which is beneficial to maintaining and improving the refractory resistance or high-temperature performance of refractory materials.

In the present invention, the melting point of boron oxide (B ₂ O ₃ ) is 450°C, and the melting point of phosphorus pentoxide (P ₂ O ₅ ) is 580 to 585°C. Adding these solid additives can make the temperature-resistant material at medium temperature (400 to 1000°C) A small amount of liquid phase is formed to promote local sintering and increase strength. At the same time, at high temperatures above 1000°C, B ₂ O ₃ and P ₂ O ₅ escape from the heat-resistant material, so that the high-temperature performance of the heat-resistant material is not negatively affected.

In the present invention, magnesium oxide (MgO) powder is added with the addition of boron oxide and/or phosphorus pentoxide. On the one hand, since MgO is an alkaline substance, it reacts with the acidic boron oxide and phosphorus pentoxide to form The gel material can also easily improve the medium-temperature strength of temperature-resistant materials; on the other hand, adding MgO can also weaken the reaction of boron oxide and phosphorus pentoxide on the magnesium oxide in spinel, causing the spinel to be decomposed, which is beneficial to improving the sharpness of the spinel. Chemical stability of spar in composite materials.

In the present invention, the above-mentioned burn-free silicon carbide-magnesia-aluminum spinel refractory material has SiC as the main crystal phase and magnesia-aluminum spinel as the secondary crystal phase; preferably, the above-mentioned secondary crystal phase fills the gaps between the above-mentioned main crystal phases. . The main crystalline phase SiC is the skeleton of the refractory material, which is resistant to high temperatures, erosion and thermal shock. The secondary phase spinel fills the gaps between the main crystal phases of silicon carbide, connects the silicon carbide particles to each other to form a network, absorbs stress and improves thermal shock resistance; it reacts with the infiltrated slag to improve the slag permeability resistance.

In the present invention, the sum of the mass fractions of SiC, MgO and Al ₂ O ₃ in the burn-free silicon carbide-magnesium aluminum spinel refractory material is greater than or equal to 95%, of which the mass fraction of SiC is 53% to 75% and Al ₂ O ₃ The mass fraction is 18% to 35%, and the MgO mass fraction is 5% to 10%. In addition, the crystal phase of refractory materials may also contain one or more of metal aluminum, corundum, periclase, aluminum phosphate, magnesium phosphate, and magnesium borate, which account for ≤10% of the total crystal phase mass fraction, among which, metal Aluminum is the residue after addition. During heat treatment, the Al-C-N-O whisker reinforcement phase is formed inside the unfired bricks, which improves the mechanical strength and slag resistance; corundum and periclase do not reduce the high temperature performance and resistance of the unfired bricks. Slag properties; aluminum phosphate, magnesium phosphate, and magnesium borate have decomposed and escaped before the slag melts and erodes when the temperature is lower than 1300°C, which will not have a negative impact on the high temperature resistance and slag resistance of the final product.

In the present invention, the apparent porosity of the unburned silicon carbide-magnesium aluminum spinel refractory material is 5% to 12%, the volume density is 2.65 to 2.90g/cm ³ , the normal temperature flexural strength is 25 to 40MPa, and the 800°C high temperature The flexural strength is 15~30MPa, and the 1400℃ high temperature flexural strength is 25~40MPa. Since the refractory material disclosed in the present invention has a non-burning property, the phenolic resin in the refractory material fills the pores inside the material, reducing the apparent porosity. The low porosity is conducive to reducing the penetration of slag and gas into the interior of the material, which can improve Material resistance to slag penetration and oxidation.

In the present invention, the above-mentioned free-burning silicon carbide-magnesium aluminum spinel refractory material includes SiC, Al ₂ O ₃ and MgO; preferably, the total mass fraction of the above-mentioned SiC, Al ₂ O ₃ and MgO is ≥95%; more preferably , the above-mentioned SiC mass fraction is 53% to 75%, the above-mentioned Al ₂ O ₃ mass fraction is 18% to 35%, and the above-mentioned MgO mass fraction is 5% to 10%.

The invention also provides a method for preparing burn-free silicon carbide-magnesium aluminum spinel refractory material, which includes the following steps:

Mix silicon carbide particles, aluminum magnesium spinel fine powder, metal aluminum powder, solid additives and binding agents evenly, first and then press them into a green body; specifically, first mix aluminum magnesium spinel fine powder, metal aluminum powder, The solid additives are mixed in advance to form a uniform solid fine powder mixture. The uniformly dispersed solid powders can fully contact and react with each other during later heat treatment and use to improve the performance and structural uniformity of the material; and then combined with silicon carbide particles. The agent is mixed evenly on the wheel-type sand mixer to form mud, and the mud is loaded into the mold to form the green body on a friction brick press, hydraulic press or vibration forming machine;

The above-mentioned green body is dried with hot air at 150-250°C for 8-24 hours, and the above-mentioned burn-free silicon carbide-magnesium aluminum spinel refractory material can be obtained without high-temperature heat treatment above 1000°C. Among them, the drying temperature should be lower than the melting point temperature of the above-mentioned organic coating to prevent the drying temperature from being too high, causing the organic coating to melt and break, causing the metal aluminum particles covered by it to be hydrated or oxidized. The molded green body adopts segmented drying temperature. The green body is left naturally for more than 4 hours and dried at 60-90°C for 4-8 hours to remove the alcohol used to dilute the phenolic resin in the green body. 110 Dry at 130°C for 4 to 8 hours to remove moisture from the green body, and dry at 150 to 250°C for 8 to 24 hours to fully solidify the resin.

In the present invention, the preparation method of the above-mentioned metal aluminum powder includes: mixing metal aluminum ions into a liquid organic polymer under an inert atmosphere, and then solidifying and separating to obtain organic-coated metal aluminum powder; preferably, the above-mentioned metal aluminum powder The particle size is 0.03~0.07mm.

Specifically, a method for preparing metal aluminum powder includes: melting an organic polymer under an inert atmosphere, dipping metal aluminum particles into the melted organic polymer, filtering out, cooling, crushing, and screening to obtain organic-coated metal. Aluminum powder; the second preparation method of metal aluminum powder includes: adding metal aluminum particles to an organic polymer dissolved in a solvent under an inert atmosphere and mixing evenly, and then evaporating the solvent to obtain organic-coated metal aluminum powder. .

The silicon carbide-magnesium aluminum spinel refractory material is stored dry and stored at room temperature. It can be built with water-containing or anhydrous refractory mud when used. It is used in reducing atmosphere kilns or inert atmosphere kilns with a maximum operating temperature not higher than 1700°C. .

In order to further illustrate the present invention, the burn-free silicon carbide-magnesia aluminum spinel refractory material provided by the present invention and its preparation method and products are described in detail below in conjunction with the examples. However, it should be understood that these examples are based on the present invention. The technical solution of the invention is premised on the implementation, and the detailed implementation mode and specific operating process are given. This is only to further illustrate the features and advantages of the invention, but not to limit the claims of the invention, and the scope of protection of the invention is not limited to Examples below.

Example 1

Weigh 30kg of fused magnesia-aluminum spinel fine powder with particle size ≤0.1mm and w(MgO)=14.2%w(Al ₂ O ₃ )=85% respectively. The particle size is ≤0.02mm and the surface is coated with polyamide with a thickness of about 5 μm. 5kg of metal aluminum powder, chemical composition w (Al ₂ O ₃ ) = 70%, w (MgO) = 22%, w (CaO) = 7.5%, particle size ≤ 0.2mm, containing magnesium aluminum spinel 70% aluminate 5kg of calcium cement, after dry mixing, mix together with 60kg of fused silicon carbide particles with a particle size of 0.1-3mm, w (SiC) = 98.5%, and 6kg of thermosetting phenolic resin binder diluted with alcohol in a wheel-type sand mixer The mud material is formed, and the mud material is put into a steel mold and formed into a 230mm×114mm×65mm standard brick body on a vibrating press. After the green body is left naturally for 24 hours, it is dried at 80°C for 6 hours, at 130°C for 4 hours, and at 180°C for 24 hours. Finally, the burning-free silicon carbide-magnesia-aluminum spinel composite refractory material is obtained.

XRD test: The silicon carbide-magnesia-aluminum spinel composite refractory material has SiC as the main crystal phase, magnesia-aluminum spinel as the secondary crystal phase, and contains 5% corundum phase and 2% aluminum metal phase. Its XRD spectrum is shown in Figure 1 As shown in the figure, the peak marked 1 is silicon carbide, the peak marked 2 is spinel, the peak marked 3 is corundum, and the peak marked 4 is metallic aluminum. The mass fraction of SiC in this composite refractory material is 59%, the mass fraction of Al ₂ O ₃ is 35%, the mass fraction of MgO is 5.5%, the apparent porosity is 10%, the bulk density is 2.75g/cm ³ , and the normal temperature flexural strength is 32MPa, 800 The high temperature flexural strength at ℃ is 19MPa, and the high temperature flexural strength at 1400℃ is 38MPa.

Example 2

Weigh 35kg of fused magnesia-aluminum spinel fine powder with particle size ≤0.1mm and w(MgO)=14.2%w(Al ₂ O ₃ )=85% respectively. The surface is coated with polyether with a thickness of about 2 μm and the particle size is ≤0.074mm. 4kg of metal aluminum powder of sulfone resin, 1kg of analytically pure boron oxide with a particle size of ≤0.2mm, dry-mixed evenly, and 60kg of fused silicon carbide particles with a particle size of 0.1-3mm, w (SiC) = 98%, and a thermosetting thermosetting material diluted with alcohol. Mix 5kg of phenolic resin binder together in a wheel sand mixer to form mud. Put the mud into a steel mold and form a 230mm × 114mm × 65mm standard brick body on a friction brick press. After the body is naturally placed for 4 hours After drying at 60°C for 6 hours, drying at 110°C for 8 hours, and drying at 150°C for 24 hours, a burning-free silicon carbide-magnesia aluminum spinel composite refractory material is obtained.

XRD test shows that the silicon carbide-magnesia-aluminum spinel composite refractory material has SiC as the main crystal phase and magnesia-aluminum spinel as the secondary crystalline phase. The mass fraction of SiC in this composite refractory material is 59%, the mass fraction of Al ₂ O ₃ is 33%, the mass fraction of MgO is 5%, the apparent porosity is 8%, the volume density is 2.78g/cm ³ , and the normal temperature flexural strength is 35MPa, 800 The high temperature flexural strength at ℃ is 15MPa, and the high temperature flexural strength at 1400℃ is 26MPa.

Example 3

Weigh 29kg of sintered magnesia-aluminum spinel fine powder with particle size ≤0.1mm and w(MgO)=21.3%w(Al ₂ O ₃ )=78% respectively. The surface is coated with polyparaphenylene with a particle size of ≤0.074mm and a thickness of about 5 μm. 3kg of metal aluminum powder of ethylene glycol diformate, 3kg of analytically pure phosphorus pentoxide with particle size ≤0.2mm, dry-mixed evenly, and 65kg of fused silicon carbide particles with particle size 0.1-2mm, w(SiC)=98.2%, 6kg of thermosetting phenolic resin binder diluted with alcohol is mixed together in a roller sand mixer to form mud. The mud is loaded into a steel mold and formed into a 230mm×114mm×65mm standard brick body on a friction brick press. After being left naturally for 8 hours, dried at 70°C for 8 hours, dried at 110°C for 8 hours, and dried at 200°C for 8 hours, the burning-free silicon carbide-magnesia aluminum spinel composite refractory material was obtained.

XRD test shows that the silicon carbide-magnesia-aluminum spinel composite refractory material has SiC as the main crystal phase, magnesia-aluminum spinel as the secondary crystal phase, and contains 10% aluminum phosphate phase. The mass fraction of SiC in this composite refractory material is 64%, the mass fraction of Al ₂ O ₃ is 26%, the mass fraction of MgO is 6.5%, the apparent porosity is 9%, the bulk density is 2.80g/cm ³ , and the normal temperature flexural strength is 32MPa, 800 The high temperature flexural strength at ℃ is 19MPa, and the high temperature flexural strength at 1400℃ is 33MPa.

Example 4

Weigh 23kg of sintered magnesia-aluminum spinel fine powder with particle size ≤0.045mm and w(MgO)=14.3%w(Al ₂ O ₃ )=85%. The surface is coated with polyethersulfone with a particle size of ≤0.045mm and a thickness of about 1 μm. Resin metal aluminum powder 2kg, particle size ≤ 0.045mm, chemical composition w (MgO) = 99.2% light-burned magnesium oxide powder 3kg, particle size ≤ 0.2mm analytically pure phosphorus pentoxide 2kg, dry-mixed evenly, with particle size 0.1-1mm , 70kg of fused silicon carbide particles with w (SiC) = 97.5%, and 7kg of thermosetting phenolic resin binder diluted with alcohol are mixed together in a wheel-type sand mixer to form mud, and the mud is loaded into a steel mold. A standard brick body of 230 mm × 114 mm × 65 mm is formed on a vibration molding machine. After the body is naturally placed for 8 hours, it is dried at 90°C for 4 hours, 110°C for 8 hours, and 200°C for 12 hours. The unburned silicon carbide-magnesia aluminum spinel is obtained. Composite refractory materials.

XRD test shows that the silicon carbide-magnesia-aluminum spinel composite refractory material has SiC as the main crystal phase and magnesia-aluminum spinel as the secondary crystalline phase. The mass fraction of SiC in this composite refractory material is 68%, the mass fraction of Al ₂ O ₃ is 23%, the mass fraction of MgO is 6.5%, the apparent porosity is 10%, the bulk density is 2.65g/cm ³ , and the normal temperature flexural strength is 25MPa, 800 The high temperature flexural strength at ℃ is 15MPa, and the high temperature flexural strength at 1400℃ is 25MPa.

Example 5

Weigh 20kg of sintered magnesia-aluminum spinel fine powder with a particle size ≤0.045mm and w(MgO)=21.5%w(Al ₂ O ₃ )=78%. The surface is coated with polyparaphenylene with a particle size ≤0.045mm and a thickness of about 5 μm. 3kg of metal aluminum powder of butylene dicarboxylate, 1kg of analytically pure magnesium oxide with a particle size ≤0.2mm, 1kg analytically pure boron oxide with a particle size ≤0.2mm, dry-mix evenly, and mix with 0.5-3mm particle size, w (SiC) = 99.5% 75kg of fused silicon carbide particles and 4.5kg of thermosetting phenolic resin binder diluted with alcohol are mixed together in a wheel sand mixer to form mud. The mud is loaded into a steel mold and formed into a φ100mm×h100mm cylindrical blank on a hydraulic press. After the green body was left naturally for 12 hours, dried at 90°C for 4 hours, dried at 130°C for 8 hours, and dried at 200°C for 12 hours, the burning-free silicon carbide-magnesia aluminum spinel composite refractory material was obtained.

XRD test shows that the silicon carbide-magnesia-aluminum spinel composite refractory material has SiC as the main crystal phase, magnesia-aluminum spinel as the secondary crystal phase, and contains 3% magnesium borate phase. The mass fraction of SiC in this composite refractory material is 75%, the mass fraction of Al ₂ O ₃ is 18%, the mass fraction of MgO is 5.5%, the apparent porosity is 11%, the bulk density is 2.70g/cm ³ , and the normal temperature flexural strength is 28MPa, 800 The high temperature flexural strength at ℃ is 22MPa, and the high temperature flexural strength at 1400℃ is 33MPa.

Example 6

Weigh 27kg of sintered magnesia-aluminum spinel fine powder with particle size ≤0.045mm and w(MgO)=21.5%w(Al ₂ O ₃ )=78%. The surface is coated with polyethersulfone with a thickness of about 8 μm. The particle size is ≤0.045mm. Resin metal aluminum powder 3kg, particle size ≤0.1mm analytically pure phosphorus pentoxide 2kg, particle size ≤0.1mm analytically pure magnesium oxide 2kg, after dry mixing, with particle size 0.1-3mm, w (SiC) = 98.5% electrofusion 66kg of silicon carbide particles and 4kg of thermosetting phenolic resin binder diluted with alcohol are mixed together in a wheel sand mixer to form mud. The mud is loaded into a steel mold and a 230mm×114mm×65mm standard brick body is formed on a hydraulic press. , after the green body was left naturally for 12 hours, dried at 90°C for 4 hours, dried at 130°C for 4 hours, and dried at 200°C for 12 hours, the burning-free silicon carbide-magnesia aluminum spinel composite refractory material was obtained.

XRD test shows that the silicon carbide-magnesia-aluminum spinel composite refractory material has SiC as the main crystal phase, magnesia-aluminum spinel as the secondary crystal phase, and contains 5% magnesium phosphate phase. The mass fraction of SiC in this composite refractory material is 65%, the mass fraction of Al ₂ O ₃ is 22%, the mass fraction of MgO is 8%, the apparent porosity is 12%, the bulk density is 2.68g/cm ³ , and the normal temperature flexural strength is 29MPa, 800 The high temperature flexural strength at ℃ is 27MPa, and the high temperature flexural strength at 1400℃ is 36MPa.

Example 7

Weigh 30kg of sintered magnesia-aluminum spinel fine powder with a particle size ≤0.074mm and w(MgO)=27.5% w(Al ₂ O ₃ )=72%. The particle size is ≤0.074mm and the surface is coated with polyamide with a thickness of about 5 μm. 3kg of metal aluminum powder, 2kg of analytically pure boron oxide with a particle size ≤0.074mm, dry-mixed evenly, and 65kg of fused silicon carbide particles with a particle size of 0.1-3mm, w (SiC) = 97.3%, and a thermosetting phenolic resin binder diluted with alcohol. 5kg are mixed together in a wheel-type sand mixer to form mud. The mud is put into a steel mold and formed on a hydraulic press to form a 230mm×114mm×65mm standard brick body. After the green body is naturally placed for 12 hours, it is dried at 90°C for 4 hours. After drying at 130°C for 4 hours and drying at 200°C for 12 hours, a burning-free silicon carbide-magnesia-aluminum spinel composite refractory material is obtained.

XRD test shows that the silicon carbide-magnesia-aluminum spinel composite refractory material has SiC as the main crystal phase, magnesium-aluminum spinel as the secondary crystal phase, and contains 3% corundum phase. The mass fraction of SiC in this composite refractory material is 63%, the mass fraction of Al ₂ O ₃ is 27%, the mass fraction of MgO is 8%, the apparent porosity is 9%, the volume density is 2.82g/cm ³ , and the normal temperature flexural strength is 36MPa, 800 The high temperature flexural strength at ℃ is 20MPa, and the high temperature flexural strength at 1400℃ is 27MPa.

Example 8

Weigh 40kg of fused magnesia-aluminum spinel fine powder with particle size ≤0.1mm, w(MgO)=24%, w(Al ₂ O ₃ )=75% respectively. The particle size is ≤0.074mm and the surface is coated with polyethylene with a thickness of about 10 μm. 2kg of amide metal aluminum powder, chemical composition w (Al ₂ O ₃ ) = 69%, w (MgO) = 22%, w (CaO) = 8%, particle size ≤ 0.2mm, containing 75% aluminum of magnesium aluminum spinel 3kg of calcium acid cement, after dry mixing, together with 55kg of fused silicon carbide particles with a particle size of 0.1-3mm, w (SiC) = 97%, and 7kg of thermosetting phenolic resin binder diluted with alcohol, are placed in a wheel sand mixer Mix to form a mud material, put the mud material into a steel mold, and form a 230mm×114mm×65mm standard brick body on a friction brick press. After the green body is naturally placed for 4 hours, it is dried at 60°C for 8 hours, 110°C for 8 hours, and 250°C. After 8 hours, the burning-free silicon carbide-magnesia-aluminum spinel composite refractory material is obtained.

XRD test shows that the silicon carbide-magnesia-aluminum spinel composite refractory material has SiC as the main crystal phase, magnesia-aluminum spinel as the secondary crystal phase, and contains 2% corundum phase. The mass fraction of SiC in this composite refractory material is 53%, the mass fraction of Al ₂ O ₃ is 35%, the mass fraction of MgO is 10%, the apparent porosity is 5%, the volume density is 2.90g/cm ³ , and the normal temperature flexural strength is 40MPa, 800 The high temperature flexural strength at ℃ is 30MPa, and the high temperature flexural strength at 1400℃ is 40MPa.

Example 9

Weigh 39kg of sintered magnesia-aluminum spinel fine powder with particle size ≤0.1mm and w(MgO)=21.5%w(Al ₂ O ₃ )=78%. The particle size is ≤0.074mm and the surface is coated with polyethersulfone with a thickness of about 5 μm. Resin metal aluminum powder 3kg, chemical composition w (Al ₂ O ₃ ) = 71%, w (MgO) = 20%, w (CaO) = 8.3%, particle size ≤ 0.2mm, containing magnesium aluminum spinel 80% aluminum 3kg of calcium acid cement, after dry mixing, together with 55kg of fused silicon carbide particles with a particle size of 0.5-3mm, w (SiC) = 98.5%, and 5kg of thermosetting phenolic resin binder diluted with alcohol, are placed in a wheel sand mixer Mix to form a mud material, put the mud material into a steel mold, and form a 230mm×114mm×65mm standard brick body on a friction brick press. After the green body is naturally placed for 24 hours, it is dried at 80°C for 6 hours, at 120°C for 6 hours, and at 180°C. After 24 hours, the burning-free silicon carbide-magnesia aluminum spinel composite refractory material is obtained.

XRD test shows that the silicon carbide-magnesia-aluminum spinel composite refractory material has SiC as the main crystal phase and magnesia-aluminum spinel as the secondary crystalline phase. The mass fraction of SiC in this composite refractory material is 54%, the mass fraction of Al ₂ O ₃ is 35%, the mass fraction of MgO is 7.5%, the apparent porosity is 9%, the bulk density is 2.82g/cm ³ , and the normal temperature flexural strength is 38MPa, 800 The high temperature flexural strength at ℃ is 19MPa, and the high temperature flexural strength at 1400℃ is 26MPa.

Example 10

Weigh 27kg of sintered magnesia-aluminum spinel fine powder with particle size ≤0.1mm and w(MgO)=21.5%w(Al ₂ O ₃ )=78% respectively. The particle size is ≤0.074mm and the surface is coated with polyethersulfone with a thickness of about 5 μm. Resin metal aluminum powder 4kg, chemical composition w (Al ₂ O ₃ ) = 70%, w (MgO) = 18%, w (CaO) = 11.5%, particle size ≤ 0.2mm, containing magnesium aluminum spinel 70% aluminum 4kg of calcium acid cement, after dry mixing, is mixed with 65kg of fused silicon carbide particles with a particle size of 0.5-3mm, w (SiC) = 98.5%, and 5kg of thermosetting phenolic resin binder diluted with alcohol in a wheel sand mixer Mix to form a mud material, put the mud material into a steel mold, and form a 230mm×114mm×65mm standard brick body on a friction brick press. After the green body is naturally placed for 24 hours, it is dried at 80°C for 6 hours, 110°C for 8 hours, and 200°C. After 24 hours, the burning-free silicon carbide-magnesia aluminum spinel composite refractory material is obtained.

XRD test shows that the silicon carbide-magnesia-aluminum spinel composite refractory material has SiC as the main crystal phase and magnesia-aluminum spinel as the secondary crystalline phase. The mass fraction of SiC in this composite refractory material is 64%, the mass fraction of Al ₂ O ₃ is 29%, the mass fraction of MgO is 6.5%, the apparent porosity is 6%, the bulk density is 2.85g/cm ³ , and the normal temperature flexural strength is 36MPa, 800 The high temperature flexural strength at ℃ is 25MPa, and the high temperature flexural strength at 1400℃ is 33MPa.

Example 11

Weigh 22kg of sintered magnesia-aluminum spinel fine powder with particle size ≤0.1mm and w(MgO)=21.5%w(Al ₂ O ₃ )=78%. The particle size is ≤0.074mm and the surface is coated with polyethersulfone with a thickness of about 5 μm. Resin metal aluminum powder 5kg, chemical composition w (Al ₂ O ₃ ) = 70%, w (MgO) = 16%, w (CaO) = 13%, particle size ≤ 0.2mm, containing magnesium aluminum spinel 65% aluminum 3kg of calcium acid cement, after dry mixing, together with 70kg of fused silicon carbide particles with a particle size of 0.5-3mm, w (SiC) = 98.5%, and 4kg of thermosetting phenolic resin binder diluted with alcohol, are placed in a wheel sand mixer Mix to form a mud material, put the mud material into a steel mold, and form a 230mm × 114mm × 65mm standard brick body on a friction brick press. After the body is naturally placed for 24 hours, it is dried at 80°C for 6 hours, 110°C for 8 hours, and 180°C. After 24 hours, the burning-free silicon carbide-magnesia aluminum spinel composite refractory material is obtained.

XRD test shows that the silicon carbide-magnesia-aluminum spinel composite refractory material has SiC as the main crystal phase, magnesia-aluminum spinel as the secondary crystal phase, and 1% aluminum metal phase. The mass fraction of SiC in this composite refractory material is 69%, the mass fraction of Al ₂ O ₃ is 25.5%, the mass fraction of MgO is 5%, the apparent porosity is 9%, the bulk density is 2.87g/cm ³ , and the normal temperature flexural strength is 40MPa, 800 The high temperature flexural strength at ℃ is 22MPa, and the high temperature flexural strength at 1400℃ is 39MPa.

Example 12

Weigh 27kg of sintered magnesia-aluminum spinel fine powder with particle size ≤0.1mm and w(MgO)=21.5%w(Al ₂ O ₃ )=78% respectively. The particle size is ≤0.074mm and the surface is coated with polyethersulfone with a thickness of about 5 μm. Resin metal aluminum powder 3kg, chemical composition w (Al ₂ O ₃ ) = 70%, w (MgO) = 16%, w (CaO) = 13.3%, particle size ≤ 0.2mm, containing magnesium aluminum spinel 70% aluminum 5kg of calcium acid cement, after dry mixing, is mixed with 65kg of fused silicon carbide particles with a particle size of 0.5-3mm, w (SiC) = 98.5%, and 4.5kg of thermosetting phenolic resin binder diluted with alcohol in a wheel sand mixer. Mix in the medium to form a mud material, put the mud material into a steel mold, and form a 230mm × 114mm × 65mm standard brick body on a friction brick press. After the body is naturally placed for 24 hours, it is dried at 80°C for 6 hours, 110°C for 8 hours, and 180°C. After drying for 24 hours, the burning-free silicon carbide-magnesia aluminum spinel composite refractory material is obtained.

XRD test shows that the silicon carbide-magnesia-aluminum spinel composite refractory material has SiC as the main crystal phase and magnesia-aluminum spinel as the secondary crystalline phase. The mass fraction of SiC in this composite refractory material is 64%, the mass fraction of Al ₂ O ₃ is 29%, the mass fraction of MgO is 6.5%, the apparent porosity is 8%, the bulk density is 2.75g/cm ³ , and the normal temperature flexural strength is 35MPa, 800 The high temperature flexural strength at ℃ is 30MPa, and the high temperature flexural strength at 1400℃ is 36MPa.

Example 13

A refractory product, including the burn-free silicon carbide-magnesium aluminum spinel refractory material prepared in Example 1, is used as the lining material of a high-temperature kiln. After the product is prepared according to the designed shape, it is built with matching fire mud at high temperatures. The interior of the kiln serves as a protective lining. During use, as the use temperature increases, different raw materials in the refractory materials react differently at different temperatures to enhance the performance of the refractory bricks. Specifically, phenolic resin provides a temperature range from normal temperature to 600 Mechanical strength of ℃, the solid additive forms a liquid phase at 400~1000℃, which improves the medium temperature strength of the material. The metal aluminum powder forms Al-C-N- with CO, O ₂ , N ₂ , etc. in the heat treatment atmosphere at 900~1500℃. The O fiber reinforcement phase improves the high temperature strength of the material.

The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and illustration. These descriptions are not intended to limit the invention to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teachings. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and its practical applications, thereby enabling others skilled in the art to make and utilize various exemplary embodiments of the invention and various different applications. Choice and change. The scope of the invention is intended to be defined by the claims and their equivalents.

Claims (10)

A kind of unburned silicon carbide-magnesium aluminum spinel refractory material, which is characterized in that the burn-free silicon carbide-magnesia aluminum spinel refractory material has SiC as the main crystal phase and magnesium aluminum spinel as the secondary crystalline phase. ; Preferably, the secondary crystalline phase fills the gaps in the main crystalline phase; And/or, the apparent porosity of the unburned silicon carbide-magnesium aluminum spinel refractory material is 5% to 12%; And/or, the volume density of the unburned silicon carbide-magnesium aluminum spinel refractory material is 2.65~2.90g/cm ³ ; And/or, the room temperature flexural strength of the unburned silicon carbide-magnesium aluminum spinel refractory material is 25-40MPa; And/or, the 800°C high temperature flexural strength of the burn-free silicon carbide-magnesium aluminum spinel refractory material is 15-30MPa; And/or, the 1400°C high temperature flexural strength of the burn-free silicon carbide-magnesium aluminum spinel refractory material is 25-40MPa. The unburned silicon carbide-magnesium aluminum spinel refractory material according to claim 1, characterized in that the unburned silicon carbide-magnesia aluminum spinel refractory material includes SiC, Al ₂ O ₃ and MgO; preferred , the total mass fraction of SiC, Al ₂ O ₃ and MgO is ≥95%; more preferably, the mass fraction of SiC is 53% to 75%, and the mass fraction of Al ₂ O ₃ is 18% to 35%, The MgO mass fraction is 5% to 10%. A kind of unburned silicon carbide-magnesium aluminum spinel refractory material, characterized in that the raw materials of the unburned silicon carbide-magnesia aluminum spinel refractory material include: solid powder and liquid binder, and the solid powder includes carbonized Silicon particles, magnesia-aluminum spinel fine powder, metallic aluminum powder and solid additives. The unburned silicon carbide-magnesium aluminum spinel refractory material according to claim 3, characterized in that the raw materials of the burn-free silicon carbide-magnesium aluminum spinel refractory material include, in parts by weight: 55 to 75 parts of silicon carbide particles; 20 to 40 parts of magnesia-aluminum spinel fine powder; 2 to 5 parts of metal aluminum powder; 1 to 5 parts of solid additives; The added amount of liquid binding agent is 4% to 7% of the total mass of the solid powder. The burn-free silicon carbide-magnesium aluminum spinel refractory material according to claim 3, characterized in that the silicon carbide particles are fused silicon carbide particles; And/or, the magnesium-aluminum spinel fine powder is sintered or fused magnesia-aluminum spinel fine powder; And/or, the metal aluminum powder is an organic coating coated on the metal aluminum particles; And/or, the solid additive is selected from one or more of calcium aluminate cement, boron oxide, and phosphorus pentoxide; preferably, the calcium aluminate cement contains alumina-magnesium spinel; And/or, the binding agent is a polymer with thermosetting properties; preferably, the binding agent is a phenolic resin. The burn-free silicon carbide-magnesium aluminum spinel refractory material according to claim 5, characterized in that the metal aluminum powder has a core-shell structure, wherein the metal aluminum is a core and the organic coating is a shell ; Preferably, the thickness of the organic coating is 1 to 10 μm; more preferably, the organic coating is selected from the group consisting of polyamide, polycarbonate, polyethylene terephthalate, and polyterephthalate. One or more of butylene formate and polyethersulfone resin. A method for preparing burn-free silicon carbide-magnesium aluminum spinel refractory material, which is characterized by including the following steps: Mix silicon carbide particles, aluminum magnesium spinel fine powder, metal aluminum powder, solid additives and binding agents evenly, and then press and shape the green body; After drying the green body at low temperature, the burn-free silicon carbide-magnesia aluminum spinel refractory material is obtained. The preparation method according to claim 7, characterized in that the preparation method of the metal aluminum powder includes: mixing metal aluminum ions into a liquid organic polymer under an inert atmosphere, and then solidifying and separating to obtain organic coating. Metal aluminum powder; preferably, the particle size of the metal aluminum particles is 0.03 to 0.07 mm. The preparation method according to claim 7, characterized in that the silicon carbide particles are fused silicon carbide particles; And/or, the magnesium-aluminum spinel fine powder is sintered or fused magnesia-aluminum spinel fine powder; And/or, the solid additive is selected from one or more of calcium aluminate cement, boron oxide, and phosphorus pentoxide; preferably, the calcium aluminate cement contains alumina-magnesium spinel; And/or, the binding agent is a polymer with thermosetting properties; preferably, the binding agent is a phenolic resin; And/or, the low-temperature drying temperature is 150-250°C, and more preferably, the low-temperature drying time is 8-24 hours. A refractory product, characterized in that it includes the burn-free silicon carbide-magnesium aluminum spinel refractory material described in any one of claims 1 to 6 or the burn-free carbonized refractory material obtained by the preparation method in any one of claims 7-9. Silicon-magnesia-aluminum spinel refractory material.

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