Low-oxygen steel smelting refractory and method for manufacturing the same

Abstract

The present application relates to a kind of low oxygen steel smelting refractory and its preparation method.The technical scheme is: with 60-75wt% calcium carbon particles, 15-25wt% calcium carbon fine powder, 2-10wt% spinel-calcium aluminate composite material and 2-5wt% calcium hydroxide as raw material, plus the raw material 2-6wt% aluminum titanate solution, stirring, compression molding, then under the condition of 120-300 ℃ vacuum drying 8-24 hours, cooling, the low oxygen steel smelting refractory is prepared.The present application has the characteristics of simple process, low cost, the prepared low oxygen steel smelting refractory has strong ability to adsorb oxide inclusions in molten steel, is high-quality refractory for low oxygen steel smelting.

Description

Technical Field

[0001] This invention belongs to the technical field of refractory materials for metallurgy. In particular, it relates to a refractory material for low-oxygen steel smelting and its preparation method. Background Technology

[0002] Oxide-nonoxide composite materials are an important direction in the development of refractory materials. Among them, carbon composite refractories are non-burning carbon composite refractories made by using high-melting-point alkaline oxides and high-melting-point carbon materials that are difficult to be wetted by slag as the main raw materials, adding various additives, and binding them with carbonaceous binders.

[0003] Currently, the most commonly used carbon composite refractory material is magnesia-carbon brick, mainly used as a lining material for converters, electric arc furnaces, and steel ladles. Its main characteristics are excellent high-temperature resistance, strong slag resistance, good thermal shock resistance, and low high-temperature creep. Magnesia-carbon refractories have become important refractory materials in the steel industry and are widely used as linings for metallurgical furnaces and containers. However, existing magnesia-carbon materials, due to the large coefficient of thermal expansion of magnesia sand, are prone to cracking and spalling during use. This damages the material's structure, making it susceptible to erosion by molten slag and steel, reducing its service performance and posing safety hazards. Furthermore, the spalling of oxide particles increases the total oxygen content of the molten steel, affecting its cleanliness.

[0004] Although carbon composite refractories played a crucial role in significantly improving the service life of refractory materials in the late 20th century, the development of clean steel production has shifted the focus from simply pursuing long service life to considering the impact of refractories on steel quality. The total oxygen content in steel is a key indicator, representing the cleanliness of the molten steel. Oxides in refractory materials are a significant source of oxide inclusions in steel. Therefore, reducing the impact of refractories on the total oxygen content of molten steel or leveraging the adsorption effect of refractories on oxide inclusions in molten steel has received increasing attention and importance.

[0005] Existing magnesia-carbon refractories increase the amount of oxide inclusions in molten steel due to structural spalling during use. While magnesia in magnesia-carbon refractories has a relatively small oxygenation effect on molten steel, its adsorption of oxide inclusions in molten steel is also very low, and it does not significantly reduce the total oxygen content of molten steel. Li Chengjiang et al. (Li Chengjiang, Zhang Zhengwei. Tundish steel purification technology [J]. Hebei Metallurgy, 2023(9):46-51.) pointed out that it is necessary to develop higher quality refractory materials to reduce pollution of molten steel and improve its cleanliness. Liu Jinglong et al. (Liu Jinglong, Luo Yan, Liu Nan et al. Wetting behavior of heavy rail steel molten steel with magnesia refractories [J], Steelmaking, 2023(2):73-80) and Li Nan (Li Nan. Reaction of Refractory Materials with Steel and Its Influence on Steel Quality [M]. Metallurgical Industry Press, 2005) pointed out that magnesia refractories are commonly used in the steelmaking industry, although they have a certain advantage in resisting molten steel erosion. However, the high-temperature thermodynamic properties of magnesia, the main raw material of magnesia refractories, are unstable and easily introduce oxygen into molten steel. Moreover, magnesia refractories have a weak ability to adsorb inclusions in molten steel, while calcium oxide has much more stable properties and will not introduce oxygen into molten steel. Although Chao Zengwu et al. (Chao Zengwu, Mu Jinwen, Chang Quanju et al. Research and optimization application of the influence of ladle material on inclusions in high carbon steel [J], Gansu Metallurgy, 2024(1):54-56) proposed the idea of ​​improving the aluminum-magnesia-carbon refractories of ladle to improve the cleanliness of molten steel, this study ignored the problem that the main raw material in this system has a weak adsorption capacity for oxide inclusions in molten steel. In addition, aluminum-magnesia-carbon refractories also have the problem of peeling during use, which will cause an increase in the content of oxide inclusions in steel. This study shows that the compliance rate of Al2O3 inclusions in molten steel after refractory material optimization is only 90%, which is due to the above reasons. Summary of the Invention

[0006] The present invention aims to overcome the shortcomings of the prior art and provides a simple and low-cost method for preparing refractory materials for low-oxygen steel smelting. The refractory materials prepared by this method have the ability to adsorb oxide inclusions in molten steel and can be used as refractory materials for smelting low-oxygen steel.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0008] Using 60–75 wt% calcium carbon particles, 15–25 wt% calcium carbon fine powder, 2–10 wt% spinel-calcium aluminate multiphase material and 2–5 wt% calcium hydroxide as raw materials, and adding 2–6 wt% of the above raw materials in an aluminotitanium ester solution, the mixture is stirred, pressed into shape, and then vacuum dried at 120–300°C for 8–24 hours and cooled to obtain a refractory material for low-oxygen steel smelting.

[0009] The method for preparing the calcium carbon particles is as follows: The calcium oxide fine powder and graphite are mixed at a mass ratio of 7:(0.9-1) to obtain a mixed powder. The mixed powder is placed in the hopper of a granulation device, and 20-30 wt% of an alumina titanate solution is added at a rotation speed of 1000-2000 r / min. When particles are formed in the device, the rotation speed is adjusted to 500-1000 r / min. After all the mixed powder has been converted into particles, the particles are removed and then kept at 110-200℃ and 1K-2KPa for 12-24 hours, followed by cooling to obtain the calcium carbon particles.

[0010] The particle size of the calcium carbon particles is 0.2–8 mm.

[0011] The calcium carbon fine powder is obtained by grinding the calcium carbon particles, and the particle size of the calcium carbon fine powder is 5-300 μm.

[0012] The spinel-calcium aluminate composite material has a particle size of 0.1–1 mm; in the spinel-calcium aluminate composite material: MgO content ≥15 wt%, Al2O3 content ≥65 wt%, and CaO content ≤15 wt%.

[0013] The calcium hydroxide contains ≥95wt% Ca(OH)2 and has a particle size of 1–300μm.

[0014] The aluminotitanium ester solution contains Ti content ≥ 4 wt% and Al content ≥ 4 wt%.

[0015] The fine calcium oxide powder has a particle size of 1–300 μm and a CaO content of ≥95 wt%.

[0016] The graphite has a particle size of 1–200 μm and a C content of ≥95%.

[0017] The pressure during the pressing process is 50MPa to 200MPa.

[0018] The vacuum degree of the vacuum drying is 50-1000 Pa.

[0019] By adopting the above technical solution, the present invention has the following advantages compared with the prior art:

[0020] 1. This invention does not require high-temperature firing, the process is simple, and the cost is low.

[0021] 2. The main raw materials used in this invention are self-made calcium carbon particles and fine powder, which can bring the following significant technical progress to the refractory materials for low oxygen steel smelting: (1) Prepare a non-segregated oxide-carbon mixture, mix and granulate, which can effectively prevent the segregation of calcium carbon components; (2) Disperse graphite evenly to prevent layered cracking in the molded products; (3) Improve the flow characteristics of powdered raw materials and improve the stability, density and non-segregation of mold feeding during molding; (4) Calcium oxide has stable thermodynamic properties, will not add oxygen to the steel or generate oxide inclusions, and has the ability to adsorb oxide inclusions in the steel; (5) Improve the thermal shock stability of refractory materials.

[0022] 3. During high-temperature use, no volume expansion reaction occurs in the refractory material system for low-oxygen steel smelting, and the problem of oxygenation in molten steel will not occur due to spalling caused by volume effect during service.

[0023] 4. The adhesive properties of calcium hydroxide used in this invention are beneficial to molding. At the same time, calcium hydroxide generates highly active calcium oxide during use, which is beneficial for adsorbing oxide inclusions in molten steel.

[0024] 5. This invention introduces a spinel-calcium aluminate multiphase material, whose typical phase composition is CaAl2O4, CaAl4O7, and MgAl2O4. The main oxide inclusions in molten steel are Al2O3 and SiO2. When the spinel-calcium aluminate multiphase material is used as a raw material for refractory materials in low-oxygen steelmaking, it reacts with the Al2O3 and SiO2 oxide inclusions in the molten steel as follows:

[0025] CaAl₂O₄ + Al₂O₃ = CaAl₄O₇ (1)

[0026] CaAl₄O₇ + 4Al₂O₃ = CaAl 12 O 19 (2)

[0027] CaAl₂O₄ + SiO₂ = CaAl₂SiO₆ (3)

[0028] CaAl2O4+2SiO2=CaAl2Si2O8 (4)

[0029] 2MgAl₂O₄ + 5SiO₂ = Mg₂Al₄Si₅O 18 (5)

[0030] The reactions in equations (1)-(5) represent the relationship between the standard Gibbs free energy and temperature. It can be seen that the enthalpy change of the relevant reactions is less than zero within the steelmaking temperature range. That is, when Al2O3 and SiO2 inclusions in the molten steel undergo disordered motion, they react with the minerals in the spinel-calcium aluminate composite material of the refractory material to generate CaAl4O7 and CaAl...12 O 19 CaAl2SiO6, CaAl2Si2O8 and Mg2Al4Si5O 18 The reaction products are retained in the refractory material, thereby achieving the purpose of removing oxide inclusions in molten steel and reducing the total oxygen content of molten steel.

[0031] The refractory material for low-oxygen steel smelting prepared by this invention was tested and found to have the following properties: CaO content of 77.51–83.72 wt%; C content of 10.12–12.62 wt%; and compressive strength of 21–340 MPa.

[0032] Therefore, the present invention has the characteristics of simple process and low cost. The refractory material prepared for low oxygen steel smelting has a strong ability to adsorb oxide inclusions in molten steel, and is a high-quality refractory material for smelting low oxygen steel. Attached Figure Description

[0033] Figure 1 This is a graph showing the relationship between temperature and spinel-calcium aluminate multiphase material adsorbing oxide inclusions in molten steel in the refractory material for low-oxygen steel smelting prepared in this invention. Detailed Implementation

[0034] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the scope of protection thereof.

[0035] A refractory material for low-oxygen steelmaking and its preparation method. The preparation method described in this specific embodiment is as follows:

[0036] Using 60–75 wt% calcium carbon particles, 15–25 wt% calcium carbon fine powder, 2–10 wt% spinel-calcium aluminate multiphase material and 2–5 wt% calcium hydroxide as raw materials, and adding 2–6 wt% of the above raw materials in an aluminotitanium ester solution, the mixture is stirred, pressed into shape, and then vacuum dried at 120–300°C for 8–24 hours and cooled to obtain a refractory material for low-oxygen steel smelting.

[0037] The method for preparing the calcium carbon particles is as follows: The calcium oxide fine powder and graphite are mixed at a mass ratio of 7:(0.9-1) to obtain a mixed powder. The mixed powder is placed in the hopper of a granulation device, and 20-30 wt% of an alumina titanate solution is added at a rotation speed of 1000-2000 r / min. When particles are formed in the device, the rotation speed is adjusted to 500-1000 r / min. After all the mixed powder has been converted into particles, the particles are removed and then kept at 110-200℃ and 1K-2KPa for 12-24 hours, followed by cooling to obtain the calcium carbon particles.

[0038] The pressure during the pressing process is 50–200 MPa.

[0039] The vacuum degree of the vacuum drying is 50-1000 Pa.

[0040] In this specific implementation:

[0041] The particle size of the calcium carbon particles is 0.2–8 mm.

[0042] The calcium carbon fine powder is obtained by grinding the calcium carbon particles, and the particle size of the calcium carbon fine powder is 5-300 μm.

[0043] The spinel-calcium aluminate composite material has a particle size of 0.1–1 mm; in the spinel-calcium aluminate composite material: MgO content ≥15 wt%, Al2O3 content ≥65 wt%, and CaO content ≤15 wt%.

[0044] The calcium hydroxide contains ≥95wt% Ca(OH)2 and has a particle size of 1–300μm.

[0045] The aluminotitanium ester solution contains Ti content ≥ 4 wt% and Al content ≥ 4 wt%.

[0046] The fine calcium oxide powder has a particle size of 1–300 μm and a CaO content of ≥95 wt%.

[0047] The graphite has a particle size of 1–200 μm and a C content of ≥95%.

[0048] The details will not be repeated in the examples.

[0049] Example 1

[0050] A refractory material for low-oxygen steelmaking and its preparation method. The preparation method described in this embodiment is as follows:

[0051] Using 60wt% calcium carbon particles, 25wt% calcium carbon fine powder, 10wt% spinel-calcium aluminate multiphase material and 5wt% calcium hydroxide as raw materials, and adding 2wt% of the above raw materials in an aluminotitanium ester solution, the mixture is stirred, pressed into shape, and then vacuum dried at 120℃ for 24 hours and cooled to obtain a refractory material for low-oxygen steel smelting.

[0052] The pressure during the pressing process is 50 MPa.

[0053] The vacuum degree of the vacuum drying is 50 Pa.

[0054] The method for preparing the calcium carbon particles is as follows: The calcium oxide fine powder and graphite are mixed at a mass ratio of 7:0.9 to obtain a mixed powder. The mixed powder is placed in the hopper of a granulation device, and a 30wt% alumina titanate solution is added at a rotation speed of 1000 r / min. When particles are formed in the device, the rotation speed is adjusted to 500 r / min. After all the mixed powder has been converted into particles, the particles are removed and then kept at 110℃ and 1 kPa for 12 hours, followed by cooling to obtain the calcium carbon particles.

[0055] The refractory material for low-oxygen steel smelting prepared in this embodiment was tested and found to have the following properties: CaO content of 77.51 wt%; C content of 10.12 wt%; and compressive strength of 21 MPa.

[0056] Example 2

[0057] A refractory material for low-oxygen steelmaking and its preparation method. The preparation method described in this embodiment is as follows:

[0058] Using 70wt% calcium carbon particles, 15wt% calcium carbon fine powder, 10wt% spinel-calcium aluminate multiphase material and 5wt% calcium hydroxide as raw materials, and adding 6wt% of the above raw materials in an aluminotitanium ester solution, the mixture is stirred, pressed into shape, and then vacuum dried at 300℃ for 8 hours and cooled to obtain a refractory material for low-oxygen steel smelting.

[0059] The pressure during the pressing process is 200 MPa.

[0060] The vacuum degree of the vacuum drying is 1000 Pa.

[0061] The method for preparing the calcium carbon particles is as follows: The calcium oxide fine powder and graphite are mixed at a mass ratio of 7:0.94 to obtain a mixed powder. The mixed powder is placed in the hopper of a granulation device, and a 20wt% alumina titanate solution is added at a rotation speed of 2000 r / min. When particles are formed in the device, the rotation speed is adjusted to 1000 r / min. After all the mixed powder has been converted into particles, the particles are removed and then kept at 200℃ and 2 kPa for 24 hours, followed by cooling to obtain the calcium carbon particles.

[0062] The refractory material for low-oxygen steel smelting prepared in this embodiment was tested and found to have the following properties: CaO content of 79.27 wt%; C content of 11.25 wt%; and compressive strength of 25.2 MPa.

[0063] Example 3

[0064] A refractory material for low-oxygen steelmaking and its preparation method. The preparation method described in this embodiment is as follows:

[0065] Using 75wt% calcium carbon particles, 21wt% calcium carbon fine powder, 2wt% spinel-calcium aluminate multiphase material and 2wt% calcium hydroxide as raw materials, and adding 6wt% of the above raw materials in an aluminotitanium ester solution, the mixture is stirred, pressed into shape, and then vacuum dried at 200℃ for 12 hours and cooled to obtain a refractory material for low-oxygen steel smelting.

[0066] The pressure during the pressing process is 150 MPa.

[0067] The vacuum degree of the vacuum drying is 500 Pa.

[0068] The method for preparing the calcium carbon particles is as follows: The calcium oxide fine powder and graphite are mixed at a mass ratio of 7:0.98 to obtain a mixed powder. The mixed powder is placed in the hopper of a granulation device, and a 25wt% alumina titanate solution is added at a rotation speed of 1500 r / min. When particles are formed in the device, the rotation speed is adjusted to 800 r / min. After all the mixed powder has been converted into particles, the particles are removed and then kept at 150℃ and 1.5 kPa for 18 hours, followed by cooling to obtain the calcium carbon particles.

[0069] The refractory material for low-oxygen steel smelting prepared in this embodiment was tested and found to have the following properties: CaO content of 83.72 wt%; C content of 12.62 wt%; and compressive strength of 31.5 MPa.

[0070] Example 4

[0071] A refractory material for low-oxygen steelmaking and its preparation method. The preparation method described in this embodiment is as follows:

[0072] Using 67wt% calcium carbon particles, 23wt% calcium carbon fine powder, 7wt% spinel-calcium aluminate multiphase material and 3wt% calcium hydroxide as raw materials, and adding 4wt% of the above raw materials in an aluminotitanium ester solution, the mixture was stirred, pressed into shape, and then vacuum dried at 250℃ for 18 hours and cooled to obtain a refractory material for low-oxygen steel smelting.

[0073] The pressure during the pressing process is 100 MPa.

[0074] The vacuum degree of the vacuum drying is 300 Pa.

[0075] The method for preparing the calcium carbon particles is as follows: The calcium oxide fine powder and graphite are mixed at a mass ratio of 7:1 to obtain a mixed powder. The mixed powder is placed in the hopper of a granulation device, and a 23wt% alumina titanate solution is added at a rotation speed of 1800 r / min. When particles are formed in the device, the rotation speed is adjusted to 700 r / min. After all the mixed powder has been converted into particles, the particles are removed and then kept at 180℃ and 1.6 kPa for 20 hours, followed by cooling to obtain the calcium carbon particles.

[0076] The refractory material for low-oxygen steelmaking prepared in this embodiment was tested and found to have the following properties: CaO content of 80.74 wt%; C content of 12.32 wt%; and compressive strength of 40 MPa.

[0077] This specific implementation method has the following advantages compared with the prior art:

[0078] 1. This specific implementation method does not require high-temperature firing, the process is simple, and the cost is low.

[0079] 2. The main raw materials used in this specific embodiment are self-made calcium carbon particles and fine powder, which can bring the following significant technical progress to the refractory materials for low oxygen steel smelting: (1) Prepare a non-segregated oxide-carbon mixture, mix and granulate, which can effectively prevent the segregation of calcium carbon components; (2) Disperse graphite evenly to prevent layered cracking in the molded products; (3) Improve the flow characteristics of powdered raw materials and improve the stability, density and non-segregation of mold feeding during molding; (4) Calcium oxide has stable thermodynamic properties, will not add oxygen to the steel or generate oxide inclusions, and has the ability to adsorb oxide inclusions in the steel; (5) Improve the thermal shock stability of refractory materials.

[0080] 3. In this specific embodiment, no volume expansion reaction occurs in the refractory material system for low-oxygen steel smelting during high-temperature use, and there will be no problem of molten steel oxygenation caused by spalling due to volume effect during service.

[0081] 4. The adhesive properties of calcium hydroxide used in this specific embodiment are beneficial to molding. At the same time, calcium hydroxide generates highly active calcium oxide during use, which is beneficial for adsorbing oxide inclusions in molten steel.

[0082] 5. This specific embodiment introduces a spinel-calcium aluminate multiphase material, whose typical phase composition is CaAl2O4, CaAl4O7, and MgAl2O4. The main oxide inclusions in molten steel are Al2O3 and SiO2. When the spinel-calcium aluminate multiphase material is used as a raw material for refractory materials in low-oxygen steelmaking, it will react with the Al2O3 and SiO2 oxide inclusions in the molten steel as follows:

[0083] CaAl₂O₄ + Al₂O₃ = CaAl₄O₇ (1)

[0084] CaAl₄O₇ + 4Al₂O₃ = CaAl 12 O 19 (2)

[0085] CaAl₂O₄ + SiO₂ = CaAl₂SiO₆ (3)

[0086] CaAl2O4+2SiO2=CaAl2Si2O8 (4)

[0087] 2MgAl₂O₄ + 5SiO₂ = Mg₂Al₄Si₅O 18 (5)

[0088] Figure 1 This is a graph showing the relationship between the Gibbs free energy and temperature of the spinel-calcium aluminate multiphase material adsorbing oxide inclusions in molten steel in the low-oxygen steelmaking refractory material prepared according to this specific embodiment; specifically, Figure 1 The reaction of equations (1)-(5) is represented by the standard Gibbs free energy versus temperature curve. Figure 1 It can be seen that the free enthalpy change of the relevant reaction is less than zero within the common steelmaking temperature range (1600–1700℃). That is, when Al2O3 and SiO2 inclusions in molten steel come into contact with the surface of the refractory material during disordered movement, they react with the minerals in the spinel-calcium aluminate multiphase material to generate CaAl4O7 and CaAl2O3. 12 O 19 CaAl2SiO6, CaAl2Si2O8 and Mg2Al4Si5O 18 The reaction products are retained in the refractory material, thereby achieving the purpose of removing oxide inclusions in molten steel and reducing the total oxygen content of molten steel.

[0089] The refractory material for low-oxygen steel smelting prepared by this invention was tested and found to have the following properties: CaO content: 77.51–83.72 wt%; C content: 10.12–12.62 wt%; compressive strength: 20–40 MPa.

[0090] Therefore, this specific embodiment has the characteristics of simple process and low cost. The refractory material prepared for low oxygen steel smelting has a strong ability to adsorb oxide inclusions in molten steel and is a high-quality refractory material for smelting low oxygen steel.

Claims

1. A method for preparing a refractory material for low-oxygen steelmaking, characterized in that, The preparation method is as follows: Using 60-75 wt% calcium carbon particles, 15-25 wt% calcium carbon fine powder, 2-10 wt% spinel-calcium aluminate multiphase material and 2-5 wt% calcium hydroxide as raw materials, and adding 2-6 wt% of the raw materials in an aluminotitanium ester solution, the mixture is stirred, pressed into shape, and then vacuum dried at 120-300℃ for 8-24 hours and cooled to obtain a refractory material for low-oxygen steel smelting. The method for preparing the calcium carbon particles is as follows: The calcium oxide fine powder and graphite are mixed at a mass ratio of 7:(0.9~1) to obtain a mixed powder. The mixed powder is placed in the hopper of a granulation device, and 20~30wt% of an alumina titanate solution is added at a rotation speed of 1000~2000 r / min. When particles are formed in the device, the rotation speed is adjusted to 500~1000 r / min. After all the mixed powder has been converted into particles, the particles are removed and then kept at 110~200℃ and 1K~2KPa for 12~24 hours, followed by cooling to obtain the calcium carbon particles. The particle size of the calcium carbon particles is 0.2~8mm; The calcium carbon fine powder is obtained by grinding the calcium carbon particles, and the particle size of the calcium carbon fine powder is 5~300μm; The phase composition of the spinel-calcium aluminate multiphase material is CaAl2O4, CaAl4O7 and MgAl2O4.

2. The method for preparing refractory materials for low-oxygen steelmaking according to claim 1, characterized in that, The spinel-calcium aluminate composite material has a particle size of 0.1~1mm; in the spinel-calcium aluminate composite material: MgO content ≥15wt%, Al2O3 content ≥65wt%, and CaO content ≤15wt%.

3. The method for preparing refractory materials for low-oxygen steelmaking according to claim 1, characterized in that, The calcium hydroxide contains ≥95wt% Ca(OH)2 and has a particle size of 1~300μm.

4. The method for preparing refractory materials for low-oxygen steelmaking according to claim 1, characterized in that, The aluminotitanium ester solution contains Ti content ≥ 4 wt% and Al content ≥ 4 wt%.

5. The method for preparing refractory materials for low-oxygen steelmaking according to claim 1, characterized in that, The fine calcium oxide powder has a particle size of 1~300μm and a CaO content ≥95wt%.

6. The method for preparing refractory materials for low-oxygen steelmaking according to claim 1, characterized in that, The graphite has a particle size of 1~200μm and a C content of ≥95%.

7. The method for preparing refractory materials for low-oxygen steelmaking according to claim 1, characterized in that, The pressure during the pressing process is 50MPa~200MPa.

8. The method for preparing refractory materials for low-oxygen steelmaking according to claim 1, characterized in that, The vacuum degree of the vacuum drying is 50~1000Pa.

9. A refractory material for low-oxygen steelmaking, characterized in that, The refractory material for low-oxygen steel smelting is prepared by the method for preparing the refractory material for low-oxygen steel smelting according to any one of claims 1 to 8.

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