Low-cost si3n4-sic-mgo composite refractory and method for producing the same

Abstract

The application relates to the technical field of refractory materials, in particular to a low-cost SiAlON-SiC-MgO composite refractory material and a preparation method thereof, which comprises the following steps: (1) raw material pretreatment; (2) mixing: electric smelting magnesia processing waste, bauxite tailing fine powder, calcined pretreated crystal silicon cutting waste and industrial AlN powder are weighed according to a mass ratio, then ethanol is used as a ball milling medium in a high-energy planetary ball mill, ball milling is carried out at a rotating speed of 300-500 r / min for 5-10 h, and mixed raw materials are formed; (3) forming: 3-8% of a binder in mass content is added into the uniformly ball-milled mixed raw materials, and green bodies are pressed under 100-200 MPa; (4) drying; (5) high-temperature carbon-embedding sintering. The SiAlON-SiC-MgO composite refractory material is prepared by adopting an one-step process carbon-embedding solid-phase reaction method with industrial waste and tailings as main raw materials, the densification degree is higher, and the comprehensive performance is better.

Description

Technical Field

[0001] This invention relates to the field of refractory materials technology, and also to the field of waste resource recycling, and particularly to a low-cost SiAlON-SiC-MgO composite refractory material and its preparation method. Background Technology

[0002] Refractory materials are fundamental materials in high-temperature industries, closely related to the development of high-temperature technologies; the two are interdependent, mutually reinforcing, and develop together. As a consumable material, refractories are primarily used in the steel industry. With the continuous development of metallurgical technology, ladle refining technology places higher demands on furnace lining materials. Currently, magnesia-carbon bricks are mostly used in the slag line section of refining ladles. High-temperature oxidation leads to a relatively porous material, reducing its performance and lifespan. Furthermore, the resulting carbon increase problem hinders the development of smelting technology to some extent. Addressing the overall problems faced by ladles, it is hoped that non-oxides can be incorporated into MgO refractories to improve their mechanical properties and chemical stability. Therefore, introducing non-oxides SiAlON and SiC into MgO refractories is expected to enhance the key properties of refractory materials.

[0003] With the development of the photovoltaic industry, the amount of photovoltaic waste has also increased significantly along with the consumption of crystalline silicon. During the crystalline silicon cutting process, nearly half of the crystalline silicon is lost as silicon powder in the cutting waste, making crystalline silicon cutting waste the largest solid waste in terms of annual output and incremental volume in the photovoltaic industry chain. This not only causes a huge waste of resources, but also causes serious environmental pollution to the air, water and soil if not handled properly.

[0004] Fused magnesia is produced by melting natural magnesite in an electric arc furnace. It has advantages such as strong slag resistance, large crystal grains, and dense structure. When fused magnesia is used in different downstream fields, it needs to be processed into magnesia aggregates and fine powders of different particle sizes. This process generates a certain amount of fused magnesia processing waste, which should be fully utilized.

[0005] Therefore, how to rationally utilize bauxite tailings, fused magnesia processing waste, and crystalline silicon cutting waste to produce SiAlON-SiC-MgO composite materials is a technical problem that urgently needs to be solved. This is of great significance for reducing the cost of magnesia refractory materials and alleviating the pressure on the corresponding industries. Summary of the Invention

[0006] In view of this, the present invention aims to overcome the defects of the prior art, and aims to improve the comprehensive performance of SiAlON-SiC-MgO composite refractory material while reducing the preparation cost of SiAlON-SiC-MgO composite refractory material. Specifically, it provides a low-cost SiAlON-SiC-MgO composite refractory material and its preparation method.

[0007] Based on the above objectives, the present invention provides a low-cost SiAlON-SiC-MgO composite refractory material, the composition and mass content of which are: SiAlON mass content of 25%~50%, SiC mass content of 15%~25%, MgO mass content of 15%~35%, and the remainder being MgAl2O4 phase.

[0008] This invention also provides a method for preparing a low-cost SiAlON-SiC-MgO composite refractory material, comprising the following steps:

[0009] (1) Raw material pretreatment:

[0010] ① After fully crushing the bauxite ore, pass it through a 200-mesh sieve to obtain fine bauxite ore powder;

[0011] ② Calcine the crystalline silicon cutting waste at 600~700 °C for 3~5 h to obtain calcined pretreated crystalline silicon cutting waste;

[0012] (2) Mixing: Weigh the fused magnesia, bauxite fine powder, calcined pretreated crystalline silicon cutting waste and industrial AlN powder according to the mass ratio, and then ball mill them in a high-energy planetary ball mill with ethanol as the ball milling medium at a speed of 300~500 r / min for 5~10 h to form a mixed raw material;

[0013] (3) Molding: Add 3% to 8% by mass of binder to the uniformly mixed raw materials from the ball mill, and press them into green blanks at 100 to 200 MPa;

[0014] (4) Drying: The pressed green bodies are dried in batches in a hot air drying oven at 100~200 ℃ for 15~30h;

[0015] (5) High-temperature sintering: Under a carbon-buried atmosphere, the dried green body is heated to 1450~1650 ℃ in a high-temperature kiln and held for 3~8 h, and then cooled with the furnace to obtain the final product.

[0016] Furthermore, by mass percentage, the chemical composition of the bauxite tailings in step (1) is: Al2O3 content is 45%~50%, SiO2 content is 3%~6%, and loss on ignition is 44~50%.

[0017] Furthermore, by mass percentage, the main chemical composition of the crystalline silicon cutting waste in step (1) is: Si content is 60%~90%, SiO2 content is 10%~20%, and it also contains a small amount of SiC and C; the Si in the crystalline silicon cutting waste melts at high temperature to form a certain amount of liquid phase, which helps to reduce the porosity of the finished product.

[0018] Furthermore, in step (2), the ratio of the amount of fused magnesia processing waste, bauxite tailings fine powder, calcined pretreated crystal silicon cutting waste, industrial AlN powder, and ethanol is (10~40)kg:(10~18)kg:(48~65)kg:(4~8)kg:150L.

[0019] Furthermore, in step (3), the adhesive is one or more of polyvinyl alcohol, liquid phenolic resin, and water glass.

[0020] Furthermore, the heating program in step (5) is as follows: the temperature is increased to 900 ℃ at a rate of 1~3 ℃ / min, and then increased to 1450~1650 ℃ at a rate of 5~10 ℃ / min.

[0021] The beneficial effects of this invention are:

[0022] This invention is the first to use fused magnesia processing waste, bauxite tailings, crystal silicon cutting waste, and industrial AlN powder as raw materials to produce SiAlON-SiC-MgO composite refractory material with excellent comprehensive performance through a one-step carbon-embedded solid-phase reaction method under pre-mixed proportions.

[0023] Under the backdrop of "carbon peaking" and "carbon neutrality," compared to conventionally chosen industrial raw materials such as MgO, SiO2, and Al2O3, fused magnesia processing waste, bauxite tailings, and crystalline silicon cutting waste, all industrial waste, exhibit significant advantages. They not only save on high raw material costs but also alleviate the environmental pressure and pollution problems caused by tailings and waste accumulation. Converting fused magnesia processing waste, lightly calcined bauxite tailings powder, and crystalline silicon cutting waste in situ into high-performance SiAlON-SiC-MgO refractory materials via carbon-embedded solid-state sintering not only achieves resource recycling and reduces production costs and environmental pollution risks but also benefits from the unique state of impurities in industrial waste, which promotes the sintering process. Furthermore, the Si in the silicon waste melts at high temperatures to form a certain amount of liquid phase, helping to reduce the porosity of the refractory material. The resulting SiAlON-SiC-MgO product has a higher degree of densification and better overall performance.

[0024] The performance indicators of the SiAlON-SiC-MgO refractory material prepared by this invention were tested and found to be as follows: apparent porosity of 19.2%~25.8%, linear shrinkage of 12.1%~25.7%, and bulk density of 2.0~2.6 g / cm³. 3 The room temperature compressive strength is 60~120 MPa, and the residual strength retention rate after two air quenchings at 1100℃ is 25%~43%. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only for this invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a microstructure diagram of the SiAlON-SiC-MgO composite refractory material prepared in Example 1 of the present invention. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments.

[0028] The performance testing of the SiAlON-SiC-MgO composite refractory materials prepared in the following examples is based on the following criteria:

[0029] The apparent porosity (Pa) and bulk density (Db) of the prepared sample were measured using the Archimedes method according to GB / T 2997-2015, and the impregnation liquid used was kerosene.

[0030] The room temperature compressive strength of the prepared specimens was measured according to GB / T 5072-2008;

[0031] Thermal shock tests were conducted according to GB / T30873-2014.

[0032] Example 1

[0033] A low-cost SiAlON-SiC-MgO composite refractory material, the composition and composition ratio of which are: 40% SiAlON by mass, 20% SiC by mass, 35% MgO by mass, and the remainder being MgAl2O4 phase.

[0034] Example 2

[0035] A low-cost SiAlON-SiC-MgO composite refractory material, the composition and composition ratio of which are: SiAlON mass content 44%, SiC mass content 18%, MgO mass content 25%, and the remainder is MgAl2O4 phase.

[0036] Example 3

[0037] A low-cost SiAlON-SiC-MgO composite refractory material, the composition and composition ratio of which are: SiAlON mass content 38%, SiC mass content 25%, MgO mass content 24%, and the remainder is MgAl2O4 phase.

[0038] Example 4

[0039] A method for preparing a low-cost SiAlON-SiC-MgO composite refractory material, the specific steps of which are as follows:

[0040] (1) Raw material pretreatment:

[0041] ① After fully crushing the bauxite tailings, pass them through a 200-mesh sieve to obtain fine bauxite tailings powder;

[0042] ② The crystalline silicon cutting waste was calcined at 600 °C for 3 h to obtain calcined pretreated crystalline silicon cutting waste;

[0043] By mass percentage, the chemical composition of the bauxite tailings is: Al2O3 content is 45%, SiO2 content is 5%, and loss on ignition is 50%; the main chemical composition of the crystalline silicon cutting waste in step (1) is: Si content is 78%, SiO2 content is 16%, and SiC+C content is 6%.

[0044] (2) Mixing: Weigh the fused magnesia processing waste, bauxite tailings fine powder, calcined pretreated crystal silicon cutting waste and industrial AlN powder in a mass ratio of 10:18:65:7, and then use ethanol as the ball milling medium in a high-energy planetary ball mill with a fused magnesia to ethanol ratio of 10kg:150L. Ball mill at 300 r / min for 5 h to form a mixed raw material.

[0045] (3) Molding: Add 5% by mass of liquid phenolic resin binder to the ball-milled and uniformly mixed raw materials, and press them into green blanks at 100MPa;

[0046] (4) Drying: The pressed green bodies are dried in batches in a hot air drying oven at 100 °C for 15 h;

[0047] (5) High-temperature sintering: Under the carbon-buried atmosphere, the dried green body is heated to 1460 ℃ in a high-temperature kiln and held for 3 hours. The specific heating program is as follows: the temperature is raised to 900 ℃ at a rate of 1 ℃ / min, then raised to 1460 ℃ at a rate of 5 ℃ / min, and then cooled with the furnace to obtain the final product.

[0048] The microstructure of the prepared SiAlON-SiC-MgO composite refractory material is shown in the figure below. Figure 1 As shown, the performance indicators of the SiAlON-SiC-MgO composite refractory material prepared in this embodiment, as tested, are as follows: apparent porosity of 24.8%, linear shrinkage rate of 12.4%, and bulk density of 2.0 g / cm³. 3 The room temperature compressive strength is 60 MPa, and the residual strength retention rate after two air quenchings at 1100 ℃ is 25%.

[0049] Example 5

[0050] A method for preparing a low-cost SiAlON-SiC-MgO composite refractory material, the specific steps of which are as follows:

[0051] (1) Raw material pretreatment:

[0052] ① After fully crushing the bauxite tailings, pass them through a 200-mesh sieve to obtain fine bauxite tailings powder;

[0053] ② The crystalline silicon cutting waste was calcined at 600 °C for 3 h to obtain calcined pretreated crystalline silicon cutting waste;

[0054] By mass percentage, the chemical composition of the bauxite tailings is: Al2O3 content is 47%, SiO2 content is 3%, and loss on ignition is 50%; the main chemical composition of the crystalline silicon cutting waste in step (1) is: Si content is 79%, SiO2 content is 15%, and SiC+C content is 6%.

[0055] (2) Mixing: The fused magnesia processing waste, bauxite tailings fine powder, calcined pretreated crystal silicon cutting waste and industrial AlN powder are weighed in a mass ratio of 20:14:58:8. Then, in a high-energy planetary ball mill, ethanol is used as the ball milling medium, and the ratio of fused magnesia to ethanol is 20kg:150L. The mixture is ball milled at 300 r / min for 8 h to form a mixed raw material.

[0056] (3) Molding: Add 3% water glass binder to the ball-milled and uniformly mixed raw materials, and press them into green blanks at 100 MPa;

[0057] (4) Drying: The pressed green bodies are dried in batches in a hot air drying oven at 150 °C for 20 h;

[0058] (5) High-temperature sintering: Under the carbon-buried atmosphere, the dried green body is heated to 1500 ℃ in a high-temperature kiln and held for 3 hours. The specific heating program is as follows: the temperature is raised to 900 ℃ at a rate of 1 ℃ / min, then raised to 1500 ℃ at a rate of 5 ℃ / min, and then cooled with the furnace to obtain the final product.

[0059] The performance indicators of the SiAlON-SiC-MgO composite refractory material prepared in this embodiment were tested as follows: apparent porosity of 23.1%, linear shrinkage rate of 16.6%, and bulk density of 2.2 g / cm³. 3 The room temperature compressive strength is 90 MPa, and the residual strength retention rate after two air quenchings at 1100 ℃ is 31%.

[0060] Example 6

[0061] A method for preparing a low-cost SiAlON-SiC-MgO composite refractory material, the specific steps of which are as follows:

[0062] (1) Raw material pretreatment:

[0063] ① After fully crushing the bauxite tailings, pass them through a 200-mesh sieve to obtain fine bauxite tailings powder;

[0064] ② The crystalline silicon cutting waste was calcined at 600 °C for 5 h to obtain calcined pretreated crystalline silicon cutting waste;

[0065] By mass percentage, the chemical composition of the bauxite tailings is: Al2O3 content is 48%, SiO2 content is 4%, and loss on ignition is 48%; the main chemical composition of the crystalline silicon cutting waste in step (1) is: Si content is 79%, SiO2 content is 16%, and SiC+C content is 5%.

[0066] (2) Mixing: Weigh the fused magnesia processing waste, bauxite tailings fine powder, calcined pretreated crystal silicon cutting waste and industrial AlN powder in a mass ratio of 30:15:54:5. Then, in a high-energy planetary ball mill, use ethanol as the ball milling medium and the ratio of fused magnesia to ethanol is 30kg:150L. Ball mill at 400 r / min for 5 h to form a mixed raw material.

[0067] (3) Molding: Add 5% polyvinyl alcohol binder to the ball-milled and uniformly mixed raw materials, and press them into green blanks at 100 MPa;

[0068] (4) Drying: The pressed green bodies are dried in batches in a hot air drying oven at 200 °C for 15 h;

[0069] (5) High-temperature sintering: Under the carbon-buried atmosphere, the dried green body is heated to 1550 ℃ in a high-temperature kiln and held for 5 hours. The specific heating program is as follows: the temperature is raised to 900 ℃ at a rate of 2 ℃ / min, then raised to 1550 ℃ at a rate of 10 ℃ / min, and then cooled with the furnace to obtain the final product.

[0070] The performance indicators of the SiAlON-SiC-MgO composite refractory material prepared in this embodiment were tested as follows: apparent porosity of 22.1%, linear shrinkage rate of 18.5%, and bulk density of 2.3 g / cm³. 3 The room temperature compressive strength is 101 MPa, and the residual strength retention rate after two air quenchings at 1100 ℃ is 35%.

[0071] Example 7

[0072] A method for preparing a low-cost SiAlON-SiC-MgO composite refractory material, the specific steps of which are as follows:

[0073] (1) Raw material pretreatment:

[0074] ① After fully crushing the bauxite tailings, pass them through a 200-mesh sieve to obtain fine bauxite tailings powder;

[0075] ② The crystalline silicon cutting waste was calcined at 700 °C for 3 h to obtain calcined pretreated crystalline silicon cutting waste;

[0076] By mass percentage, the chemical composition of the bauxite tailings is: Al2O3 content is 49%, SiO2 content is 5%, and loss on ignition is 46%; the main chemical composition of the crystalline silicon cutting waste in step (1) is: Si content is 79%, SiO2 content is 16%, and SiC+C content is 5%.

[0077] (2) Mixing: Weigh the fused magnesia processing waste, bauxite tailings fine powder, calcined pretreated crystal silicon cutting waste and industrial AlN powder in a mass ratio of 40:14:48:5, and then use ethanol as the ball milling medium in a high-energy planetary ball mill with a fused magnesia to ethanol ratio of 40kg:150L. Ball mill at 500 r / min for 5 h to form a mixed raw material.

[0078] (3) Molding: Add 5% by mass of polyvinyl alcohol binder to the ball-milled and uniformly mixed raw materials, and press them into green blanks at 200 MPa;

[0079] (4) Drying: The pressed green bodies are dried in batches in a hot air drying oven at 200 °C for 20 h;

[0080] (5) High-temperature sintering: Under the carbon-buried atmosphere, the dried green body is heated to 1600 ℃ in a high-temperature kiln and held for 3 hours. The specific heating program is as follows: the temperature is raised to 900 ℃ at a rate of 2 ℃ / min, then raised to 1600 ℃ at a rate of 8 ℃ / min, and then cooled with the furnace to obtain the final product.

[0081] The performance indicators of the SiAlON-SiC-MgO composite refractory material prepared in this embodiment were tested as follows: apparent porosity of 20.8%, linear shrinkage rate of 21.9%, and bulk density of 2.41 g / cm³. 3 The room temperature compressive strength is 112 MPa, and the residual strength retention rate after two air quenchings at 1100 ℃ is 40%.

[0082] Example 8

[0083] A method for preparing a low-cost SiAlON-SiC-MgO composite refractory material, the specific steps of which are as follows:

[0084] (1) Raw material pretreatment:

[0085] ① After fully crushing the bauxite tailings, pass them through a 200-mesh sieve to obtain fine bauxite tailings powder;

[0086] ② The crystalline silicon cutting waste was calcined at 700 °C for 3 h to obtain calcined pretreated crystalline silicon cutting waste;

[0087] By mass percentage, the chemical composition of the bauxite tailings is: Al2O3 content is 49%, SiO2 content is 4%, and loss on ignition is 47%; the main chemical composition of the crystalline silicon cutting waste in step (1) is: Si content is 79%, SiO2 content is 16%, and SiC+C content is 5%.

[0088] (2) Mixing: Weigh the fused magnesia processing waste, bauxite tailings fine powder, calcined pretreated crystal silicon cutting waste and industrial AlN powder in a mass ratio of 25:16:55:4. Then, in a high-energy planetary ball mill, use ethanol as the ball milling medium and the ratio of fused magnesia to ethanol is 25kg:150L. Ball mill at 400 r / min for 10 h to form a mixed raw material.

[0089] (3) Molding: Add 8% by mass of liquid phenolic resin to the ball-milled and uniformly mixed raw materials, and press them into green bodies at 150 MPa;

[0090] (4) Drying: The pressed green bodies are dried in batches in a hot air drying oven at 150 °C for 30 h;

[0091] (5) High-temperature sintering: Under the carbon-buried atmosphere, the dried green body is heated to 1550 ℃ in a high-temperature kiln and held for 8 hours. The specific heating program is as follows: the temperature is raised to 900 ℃ at a rate of 3 ℃ / min, then raised to 1550 ℃ at a rate of 10 ℃ / min, and then cooled with the furnace to obtain the final product.

[0092] The performance indicators of the SiAlON-SiC-MgO composite refractory material prepared in this embodiment were tested as follows: apparent porosity of 21.7%, linear shrinkage rate of 21.2%, and bulk density of 2.4 g / cm³. 3 The room temperature compressive strength is 105 MPa, and the residual strength retention rate after two air quenchings at 1100 ℃ is 39%.

[0093] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of the invention (including the claims) is limited to these examples; within the framework of the invention, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of the different aspects of the invention as described above, which are not provided in the details for the sake of brevity.

[0094] This invention is intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A low-cost SiAlON-SiC-MgO composite refractory material, characterized in that, Its composition and mass content are as follows: SiAlON mass content is 25%~50%, SiC mass content is 15%~25%, MgO mass content is 15%~35%, and the remainder is MgAl2O4 phase; The method for preparing a low-cost SiAlON-SiC-MgO composite refractory material includes the following steps: (1) Raw material pretreatment: ① After fully crushing the bauxite tailings, pass them through a 200-mesh sieve to obtain fine bauxite tailings powder; ② Calcine the crystalline silicon cutting waste at 600~700 °C for 3~5 h to obtain calcined pretreated crystalline silicon cutting waste; (2) Mixing: Weigh the fused magnesia processing waste, bauxite tailings fine powder, calcined pretreated crystal silicon cutting waste and industrial AlN powder according to the mass ratio, and then ball mill them in a high-energy planetary ball mill with ethanol as the ball milling medium at a speed of 300~500 r / min for 5~10 h to form a mixed raw material; In step (2), the ratio of the amount of fused magnesia processing waste, bauxite tailings fine powder, calcined pretreated crystal silicon cutting waste, industrial AlN powder, and ethanol is (10~40)kg:(10~18)kg:(48~65)kg:(4~8)kg:150L. (3) Molding: Add 3% to 8% by mass of binder to the uniformly mixed raw materials from the ball mill, and press them into green blanks at 100 to 200 MPa; (4) Drying: The pressed green bodies are dried in batches in a hot air drying oven at 100~200 ℃ for 15~30 h; (5) High-temperature sintering: Under a carbon-buried atmosphere, the dried green body is heated to 1450~1650 ℃ in a high-temperature kiln and held for 3~8 h, and then cooled with the furnace to obtain the final product.

2. The method for preparing a low-cost SiAlON-SiC-MgO composite refractory material according to claim 1, characterized in that, Includes the following steps: (1) Raw material pretreatment: ① After fully crushing the bauxite tailings, pass them through a 200-mesh sieve to obtain fine bauxite tailings powder; ② Calcine the crystalline silicon cutting waste at 600~700 °C for 3~5 h to obtain calcined pretreated crystalline silicon cutting waste; (2) Mixing: Weigh the fused magnesia processing waste, bauxite tailings fine powder, calcined pretreated crystal silicon cutting waste and industrial AlN powder according to the mass ratio, and then ball mill them in a high-energy planetary ball mill with ethanol as the ball milling medium at a speed of 300~500 r / min for 5~10 h to form a mixed raw material; (3) Molding: Add 3% to 8% by mass of binder to the uniformly mixed raw materials from the ball mill, and press them into green blanks at 100 to 200 MPa; (4) Drying: The pressed green bodies are dried in batches in a hot air drying oven at 100~200 ℃ for 15~30 h; (5) High-temperature sintering: Under a carbon-buried atmosphere, the dried green body is heated to 1450~1650 ℃ in a high-temperature kiln and held for 3~8 h, and then cooled with the furnace to obtain the final product.

3. The method for preparing a low-cost SiAlON-SiC-MgO composite refractory material according to claim 2, characterized in that, The chemical composition of the bauxite tailings in step (1) by mass percentage is as follows: Al2O3 content is 45%~50%, SiO2 content is 3%~6%, and loss on ignition is 44~50%.

4. The method for preparing a low-cost SiAlON-SiC-MgO composite refractory material according to claim 2, characterized in that, By mass percentage, the main chemical composition of the crystalline silicon cutting waste in step (1) is: Si content of 60%~90%, SiO2 content of 10%~20%, and also contains a small amount of SiC and C.

5. A method for preparing a low-cost SiAlON-SiC-MgO composite refractory material according to any one of claims 2-4, characterized in that, In step (3), the adhesive is one or more of polyvinyl alcohol, liquid phenolic resin, and water glass.

6. A method for preparing a low-cost SiAlON-SiC-MgO composite refractory material according to any one of claims 2-4, characterized in that, The specific heating program in step (5) is as follows: heat up to 900 ℃ at a rate of 1~3 ℃ / min, and then heat up to 1450~1650 ℃ at a rate of 5~10 ℃ / min.

Images