Continuous casting tundish slag wall castable and preparation method thereof

Abstract

The invention provides a continuous casting tundish slag blocking wall castable and a preparation method thereof. The continuous casting tundish slag blocking wall castable is prepared from the following raw materials in parts by mass: 20-60 parts of scrap steel ladle precast blocks, 15-30 parts of ferrovanadium slag, 8-10 parts of white corundum fine powder, 11-20 parts of magnesia, 8-17 parts of alpha-alumina micro powder, 0.1-1 part of organic fibers, 1-2 parts of Nd2O3, 3-5 parts of cement and 0.5-2 parts of steel fibers. According to the continuous casting tundish slag-blocking wall castable, the vanadium iron slag and the scrap steel ladle precast blocks are used as aggregates to replace traditional refractory materials such as white corundum and alumina, and the production and manufacturing cost of a slag-blocking wall is greatly reduced; nd2O3 is added to generate a new phase with impurities, so that the strength performance and the slag permeability resistance of the slag wall castable are improved.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of refractory materials, and particularly relates to a continuous casting tundish slag retaining wall castable and a preparation method thereof. BACKGROUND

[0002] With the continuous development of steel technology, higher requirements are put forward for the quality of molten steel. As a container for storing molten steel, the continuous casting tundish is used in the continuous production process of continuous casting. Due to the uneven flow of molten steel in the tundish, the flow is fast in some places and slow in some places, and especially there is a stagnant zone of inactive molten steel in the bottom region of the tundish, which makes it difficult for inclusions to float up. In order to fully and effectively utilize the volume of the tundish and promote the floating of inclusions, a flow stabilizer, a slag retaining wall and a slag dam are arranged in the tundish.

[0003] During the use of the tundish slag retaining wall, the liquid level fluctuation caused by the falling molten steel of the long nozzle in the impact zone makes the slag line part of the slag retaining wall be subjected to scouring and chemical corrosion reaction of the tundish slag, and high requirements are put forward for the material of the slag retaining wall. The slag retaining wall is usually integrally vibrated and formed by using high alumina castable or magnesia-alumina castable. The Chinese patent document with the publication number CN103771885B discloses a castable for a slag retaining wall and a slag retaining wall, which adopts a magnesia-alumina castable composed of the following components: 8-20mm bauxite, 5-8mm bauxite, 3-5mm bauxite, 1-3mm bauxite, 0-1mm bauxite, bauxite with a particle size of 200 mesh, 0-1mm magnesia, magnesia with a particle size of 200 mesh, silicon powder, steel fiber, sodium hexametaphosphate and organic fiber. However, the high alumina castable or the magnesia-alumina castable puts forward high requirements for the quality of the main raw materials, resulting in that the price of the castable for producing the slag retaining wall is high, and the refractory material enterprises are under certain cost pressure. In addition, the severely eroded parts of the slag retaining wall after being taken offline are mainly concentrated in the slag line position, and the slag erosion resistance of the slag retaining wall still needs to be improved. SUMMARY

[0004] The technical problem solved by the application is to provide a continuous casting tundish slag retaining wall castable and a preparation method thereof. Vanadium slag and scrap steel ladle precast block are used as aggregates to replace traditional white corundum, bauxite and other refractory materials, so that the production and manufacturing cost of the slag retaining wall is greatly reduced. Nd2O3 is added to generate a new phase with impurities, so that the strength performance and slag penetration resistance of the slag retaining wall castable are improved.

[0005] In order to solve the above problems, one aspect of the application provides a continuous casting tundish slag retaining wall castable, and the preparation raw materials thereof include the following components in mass fraction:

[0006] The steel ladle precast block 20-60 parts, vanadium iron slag 15-30 parts, white corundum powder 8-10 parts, magnesite 11-20 parts, alpha-alumina powder 8-17 parts, organic fiber 0.1-1 part, Nd2O3 1-2 parts, cement 3-5 parts, steel fiber 0.5-2 parts.

[0007] Preferably, the preparation raw materials include the following components in mass fraction:

[0008] The steel ladle precast block 20-60 parts, vanadium iron slag 15-30 parts, white corundum powder 8-10 parts, magnesite 11-20 parts, alpha-alumina powder 8-17 parts, organic fiber 0.1-1 part, Nd2O3 1-2 parts, cement 3-5 parts, steel fiber 0.5-2 parts.

[0009] Preferably, the mass ratio of the total mass of the steel ladle precast block and the vanadium iron slag to the mass of Nd2O3 is 30-50:1.

[0010] Preferably, the mass ratio of the steel ladle precast block to the vanadium iron slag is 5-15:3.

[0011] Preferably, the steel ladle precast block includes steel ladle precast blocks with a particle size of 15-5mm and steel ladle precast blocks with a particle size of 5-0mm; the mass ratio of the steel ladle precast blocks with a particle size of 15-5mm to the steel ladle precast blocks with a particle size of 5-0mm is 1:0.3-3.

[0012] Preferably, the vanadium iron slag includes vanadium iron slag with a particle size of 3-1mm and vanadium iron slag with a particle size of 1-0mm; the mass ratio of the vanadium iron slag with a particle size of 3-1mm to the vanadium iron slag with a particle size of 1-0mm is 1:0.25-1.

[0013] Preferably, the white corundum powder has a particle size of 200 mesh;

[0014] The magnesite includes magnesite particles with a particle size of 1-0mm and magnesite powder with a particle size of 200 mesh; the mass ratio of the magnesite particles with a particle size of 1-0mm to the magnesite powder with a particle size of 200 mesh is 1:0.6-2;

[0015] The alpha-alumina powder includes alpha-alumina powder with a particle size of 3μm and alpha-alumina powder with a particle size of 1μm; the mass ratio of the alpha-alumina powder with a particle size of 3μm to the alpha-alumina powder with a particle size of 1μm is 1:0.375-1.8.

[0016] Preferably, the Al2O3 content in the steel ladle precast block is greater than 75wt%, the CaO content is less than 5wt%, and the Fe2O3 content is less than 2wt%; the water absorption of the steel ladle precast block is 1%-2%, and the particle density is 2.7-2.9g / cm 3 ;

[0017] The content of Al2O3 in the vanadium-iron slag is 75wt%-80wt%, the content of MgO is 11wt%-14wt%, the content of CaO is 2wt%-85wt%, and the content of V2O3 is 1.7wt%-2.3wt%, and the water absorption rate of the vanadium-iron slag is 1.5%-2%;

[0018] The content of Al2O3 in the alumina powder is greater than 99wt%, and the content of MgO in the magnesia is greater than 95wt%.

[0019] Preferably, the preparation raw material further comprises 0.1-0.5 parts of high-activity alumina.

[0020] Another aspect of the present application provides a preparation method of the continuous casting tundish slag stopping wall castable, comprising the following steps:

[0021] The preparation raw material of the continuous casting tundish slag stopping wall castable is mixed and dry-mixed to obtain the continuous casting tundish slag stopping wall castable.

[0022] Compared with the prior art, the present application has the following beneficial effects:

[0023] The continuous casting tundish slag stopping wall castable of the present application uses vanadium-iron slag and scrap steel ladle precast block as the aggregate to replace the traditional white corundum, bauxite and other refractory materials, greatly reduces the production cost of the slag stopping wall, improves the economic benefit of the enterprise, and recycles the vanadium-iron slag, scrap steel ladle precast block and other resources, further reducing the impact on the environment.

[0024] The continuous casting tundish slag stopping wall castable of the present application uses vanadium-iron slag-scrap steel ladle precast block as the aggregate to provide a skeleton structure, and the active components such as CaO and FeO in the two raw materials react with Al2O3 and SiO2 in the matrix at high temperature (>1300℃), the reaction product (such as iron-aluminum spinel) forms a continuous solid solution network at the aggregate-matrix interface, inhibits high-temperature grain boundary sliding (the main cause of creep), and improves the creep resistance of the slag stopping wall castable. The present application adds Nd2O3, which can react with impurities such as CaO and SiO2 to generate a new high-melting-point phase Ca4Nd6O(SiO4)6, which can reduce the reaction between impurities CaO, SiO2 and MgO, reduce the content of silicate liquid phase, and reconstruct the grain boundary phase, so that the densification degree of the material is improved, and the slag penetration resistance of the material is improved. Furthermore, at high temperature, Nd2O3 can also chemically react with SiO2 in the steel slag to generate stable rare earth silicates or perovskite-type minerals, reduce the sintering temperature, fill the gaps between the scrap steel ladle precast block and the vanadium-iron slag, hinder the migration of the grain boundary, thereby refining the grain, and improving the densification of the castable. Therefore, adding an appropriate amount of Nd2O3 can improve the slag penetration resistance of the material, and also improve its high-temperature performance. DETAILED DESCRIPTION

[0025] The technical solutions of the present application will be described clearly and completely below in combination with the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by those skilled in the art without creative work are within the protection scope of the present application.

[0026] One aspect of the embodiments of the present application provides a continuous casting tundish slag stopping wall castable, raw materials for preparing the same include the following components in mass fraction:

[0027] The waste steel ladle precast block is 20-60 parts, vanadium slag is 15-30 parts, white corundum fine powder is 8-10 parts, magnesia is 11-20 parts, alpha-alumina micro powder is 8-17 parts, organic fiber is 0.1-1 part, Nd2O3 is 1-2 parts, cement is 3-5 parts, and steel fiber is 0.5-2 parts.

[0028] The continuous casting tundish slag stopping wall castable of the embodiments of the present application uses vanadium slag and waste steel ladle precast block as aggregate to replace traditional white corundum, bauxite and other refractory materials, greatly reduces the production cost of the slag stopping wall, improves the economic benefit of the enterprise, and recycles vanadium slag, steel ladle precast block and other resources, further reduces the impact on the environment.

[0029] The continuous casting tundish slag stopping wall castable of the embodiment of the present application provides a skeleton structure with vanadium iron slag-scrap steel ladle precast blocks as aggregate, and the active components such as CaO and FeO in the two raw materials react with Al2O3 and SiO2 in the matrix at high temperature (>1300℃), and the reaction products (such as iron-aluminum spinel) form a continuous solid solution network at the aggregate-matrix interface, which inhibits high-temperature grain boundary sliding (the main cause of creep), and improves the creep resistance of the slag stopping wall castable. The scrap steel ladle precast block is a waste refractory material generated after the inner lining of the ladle is replaced in the steel metallurgy industry, and its efficient recycling is of great significance to reduce costs and reduce environmental pollution, but the precast block after recycling contains false particles, low-melting substances and impurities such as CaO and SiO2. The impurities such as CaO and SiO2 in the scrap steel ladle precast block and the vanadium iron slag are easy to react with MgO to form composite oxides such as calcium-magnesium olivine, and such composite oxides have poor refractory properties and will melt into liquid phase at high temperature, and provide a channel for the penetration of steel slag, resulting in a decrease in the performance of the material, so compared with the previous corundum as aggregate, the use of scrap steel ladle precast blocks and vanadium iron slag as aggregate will result in a decrease in the slag resistance and high-temperature strength of the castable. In order to further compensate for this problem, the present application adds Nd2O3, which can react with impurities such as CaO and SiO2 to generate a new high-melting-point phase Ca4Nd6O(SiO4)6, which can reduce the reaction of impurities CaO and SiO2 with MgO, reduce the content of silicate liquid phase, and reconstruct the grain boundary phase, so that the material is densified, and the slag penetration resistance of the material is improved. Moreover, at high temperature, Nd2O3 can also react with SiO2 in the steel slag to generate stable rare earth silicates or perovskite-type minerals, reduce the sintering temperature, fill the gaps between the scrap steel ladle precast blocks and the vanadium iron slag, hinder the migration of the grain boundary, thereby refining the grains and improving the denseness of the castable. Therefore, the addition of an appropriate amount of Nd2O3 can improve the slag penetration resistance of the material, and also improve its high-temperature performance.

[0030] Preferably, the preparation raw materials include the following components in mass fraction:

[0031] The scrap steel ladle precast block is 40-60 parts, the vanadium iron slag is 15-20 parts, the white corundum fine powder is 8-10 parts, the magnesia is 11-15 parts, the alpha-alumina micropowder is 8-12 parts, the organic fiber is 0.1-0.5 parts, the Nd2O3 is 1.2-1.8 parts, the cement is 3-5 parts, and the steel fiber is 0.8-1.2 parts.

[0032] When the above preferred mass fraction range is used, the continuous casting tundish slag stopping wall castable has better high-temperature performance and slag penetration resistance.

[0033] Preferably, the mass ratio of the total content of the scrap ladle precast block and vanadium iron slag to Nd2O3 is 30-50:1. If the total content of the scrap ladle precast block and vanadium iron slag is too high and Nd2O3 is too low, the scrap ladle precast block and vanadium iron slag cannot fully react with the impurities CaO and SiO2 therein, and it is difficult to effectively reduce the silicate liquid phase content, lower the sintering temperature, and refine the grains, so that the compactness and slag penetration resistance are limitedly improved. If the total content of the scrap ladle precast block and vanadium iron slag is too low and Nd2O3 is too much, not only Nd2O3 is wasted and the cost is increased, but also the material structure stability can be affected due to the excessively violent reaction, so the ratio of the two needs to be appropriate. When the above ratio is adopted, the continuous casting tundish slag stopping wall castable has better comprehensive performance.

[0034] Preferably, the mass ratio of the scrap ladle precast block to vanadium iron slag is 5-15:3. Because the contents of alumina and magnesia in the scrap ladle precast block and vanadium iron slag are different, the types and contents of impurities are different, and the particle sizes of the two wastes are different, the reaction activities, reaction degrees, and influences on the performance of the castable (such as compactness and slag penetration resistance) of the scrap ladle precast block and vanadium iron slag with other components in the raw material are different, so the mass ratio of the two needs to be adjusted to realize the complementary advantages of the raw materials, make the reaction sufficient and reasonable, and thus optimize the comprehensive performance of the castable. When the above ratio is adopted, the continuous casting tundish slag stopping wall castable has better comprehensive performance.

[0035] Preferably, the scrap ladle precast block includes scrap ladle precast blocks with particle sizes of 15-5 mm and scrap ladle precast blocks with particle sizes of 5-0 mm, and the mass ratio of the scrap ladle precast blocks with particle sizes of 15-5 mm to the scrap ladle precast blocks with particle sizes of 5-0 mm is 1:0.3-3.

[0036] Preferably, the vanadium iron slag includes vanadium iron slag with particle sizes of 3-1 mm and vanadium iron slag with particle sizes of 1-0 mm, and the mass ratio of the vanadium iron slag with particle sizes of 3-1 mm to the vanadium iron slag with particle sizes of 1-0 mm is 1:0.25-1.

[0037] The scrap ladle precast block and vanadium iron slag with different particle sizes are used in combination. The particles with larger particle sizes can constitute the framework of the castable, provide strength and wear resistance, and the particles with smaller particle sizes can fill the gaps between the framework, reduce the porosity, and improve the compactness. Meanwhile, the combination of different particle sizes can also optimize the particle packing structure, so that the castable has more uniform thermal expansion and shrinkage behavior at high temperature, reduces the generation of cracks, and thus improves the comprehensive performance such as slag penetration resistance and thermal shock resistance.

[0038] Preferably, the white corundum fine powder has a particle size of 200 mesh.

[0039] Preferably, the magnesia includes magnesia particles with a particle size of 1-0 mm and magnesia fine powder with a particle size of 200 mesh; the mass ratio of the magnesia particles with a particle size of 1-0 mm to the magnesia fine powder with a particle size of 200 mesh is 1:0.6-2.

[0040] Preferably, the α-alumina micropowder includes α-alumina micropowder with a particle size of 3 μm and α-alumina micropowder with a particle size of 1 μm; the mass ratio of the α-alumina micropowder with a particle size of 3 μm to the α-alumina micropowder with a particle size of 1 μm is 1:0.375-1.8.

[0041] Preferably, the ladle precast block has an Al2O3 content of greater than 75 wt%, a CaO content of less than 5 wt%, and a Fe2O3 content of less than 2 wt%; the water absorption of the ladle precast block is 1%-2%, and the particle density is 2.7-2.9 g / cm 3 ;

[0042] The Al2O3 content of the vanadium iron slag is 75 wt%-80 wt%, the MgO content is 11 wt%-14 wt%, the CaO content is 2 wt%-85 wt%, and the V2O3 content is 1.7 wt%-2.3 wt%; the water absorption of the vanadium iron slag is 1.5%-2%;

[0043] The Al2O3 content of the alumina micropowder is greater than 99 wt%, and the MgO content of the magnesia is greater than 95 wt%.

[0044] Preferably, the preparation raw material further includes 0.1-0.5 parts of high-activity alumina. The high-activity alumina, as a water reducing agent, can reduce the water consumption, improve the fluidity of the material, enhance the strength and durability of the material, and optimize the construction performance.

[0045] Another aspect of the present application provides a preparation method of the continuous casting tundish slag stopping wall castable described above, including the following steps:

[0046] Mixing the preparation raw material of the continuous casting tundish slag stopping wall castable, and performing dry mixing to obtain the continuous casting tundish slag stopping wall castable.

[0047] In each of the following embodiments, the Al2O3 content of the ladle precast block is greater than 75 wt%, the CaO content is less than 5 wt%, and the Fe2O3 content is less than 2 wt%; the water absorption of the ladle precast block is 1%-2%, and the particle density is 2.7-2.9 g / cm 3The content of Al2O3 in the vanadium-iron slag is 75wt%-80wt%, the content of MgO is 11wt%-14wt%, the content of CaO is 2wt%-85wt%, the content of V2O3 is 1.7wt%-2.3wt%, and the water absorption of the vanadium-iron slag is 1.5%-2%. The content of Al2O3 in the alumina micropowder is greater than 99wt%, and the content of MgO in the magnesia is greater than 95wt%.

[0048] Example 1

[0049] The preparation raw materials of the continuous casting tundish slag stopping wall castable of the example include the following components in mass fraction:

[0050] 25 parts of scrap ladle precast block with a particle size of 15-5mm, 25 parts of scrap ladle precast block with a particle size of 5-0mm, 10 parts of vanadium-iron slag with a particle size of 3-1mm, 5 parts of vanadium-iron slag with a particle size of 1-0mm, 8 parts of white corundum fine powder with a particle size of 200 mesh, 5 parts of magnesia particles with a particle size of 1-0mm, 6 parts of magnesia fine powder with a particle size of 200 mesh, 5 parts of α-alumina micropowder with a particle size of 3μm, 5 parts of α-alumina micropowder with a particle size of 1μm, 0.2 parts of organic fiber, 1.5 parts of Nd2O3, 4 parts of cement, 1 part of steel fiber, and 0.3 parts of high-activity alumina (model KF51S, purchased from Leiket Chongqing Chemical Products Co., Ltd.).

[0051] The preparation method of the continuous casting tundish slag stopping wall castable of the example includes the following steps:

[0052] The preparation raw materials are mixed according to the set proportion and particle size, and dry mixing is performed for 4-5 minutes to obtain the continuous casting tundish slag stopping wall castable.

[0053] The continuous casting tundish slag stopping wall castable is additionally stirred with 6wt% of water for 3-4 minutes, vibration casting is performed to discharge the bubbles in the castable until the castable is fully vibrated and compacted, standard strip-shaped samples with a size of 40mm×40mm×160mm are prepared, the samples are demolded after natural curing for 24h, and the samples are placed in an oven for drying at 110℃ for 24h.

[0054] Example 2

[0055] The preparation raw materials of the continuous casting tundish slag stopping wall castable of the example include the following components in mass fraction:

[0056] 30 parts of scrap ladle preform block with particle size of 15-5 mm, 30 parts of scrap ladle preform block with particle size of 5-0 mm, 9 parts of vanadium iron slag with particle size of 3-1 mm, 9 parts of vanadium iron slag with particle size of 1-0 mm, 9 parts of white corundum fine powder with particle size of 200 mesh, 6 parts of magnesia particles with particle size of 1-0 mm, 7 parts of magnesia fine powder with particle size of 200 mesh, 6 parts of α-alumina micropowder with particle size of 3 μm, 6 parts of α-alumina micropowder with particle size of 1 μm, 0.1 part of organic fiber, 1.2 parts of Nd2O3, 5 parts of cement, 0.8 part of steel fiber, and 0.4 part of high-activity alumina.

[0057] The preparation method and the sample preparation method of the continuous casting tundish slag stopping wall castable of the example are the same as those of example 1.

[0058] Example 3

[0059] The continuous casting tundish slag stopping wall castable of the example comprises the following components in parts by mass:

[0060] 30 parts of scrap ladle preform block with particle size of 15-5 mm, 30 parts of scrap ladle preform block with particle size of 5-0 mm, 9 parts of vanadium iron slag with particle size of 3-1 mm, 9 parts of vanadium iron slag with particle size of 1-0 mm, 9 parts of white corundum fine powder with particle size of 200 mesh, 6 parts of magnesia particles with particle size of 1-0 mm, 7 parts of magnesia fine powder with particle size of 200 mesh, 6 parts of α-alumina micropowder with particle size of 3 μm, 6 parts of α-alumina micropowder with particle size of 1 μm, 0.1 part of organic fiber, 1.2 parts of Nd2O3, 5 parts of cement, 0.8 part of steel fiber, and 0.4 part of high-activity alumina.

[0061] The preparation method and the sample preparation method of the continuous casting tundish slag stopping wall castable of the example are the same as those of example 1.

[0062] Example 4

[0063] The continuous casting tundish slag stopping wall castable of the example comprises the following components in parts by mass:

[0064] 30 parts of scrap ladle preform block with particle size of 15-5 mm, 30 parts of scrap ladle preform block with particle size of 5-0 mm, 9 parts of vanadium iron slag with particle size of 3-1 mm, 9 parts of vanadium iron slag with particle size of 1-0 mm, 9 parts of white corundum fine powder with particle size of 200 mesh, 6 parts of magnesia particles with particle size of 1-0 mm, 7 parts of magnesia fine powder with particle size of 200 mesh, 6 parts of α-alumina micropowder with particle size of 3 μm, 6 parts of α-alumina micropowder with particle size of 1 μm, 0.1 part of organic fiber, 1.2 parts of Nd2O3, 5 parts of cement, 0.8 part of steel fiber, and 0.4 part of high-activity alumina.

[0065] The preparation method and the sample preparation method of the continuous casting tundish slag stopping wall castable of the example are the same as those of example 1.

[0066] Example 5

[0067] The ladle slag stopping wall castable of the present example is prepared from the following components in mass fraction:

[0068] 30 parts of scrap ladle precast block with particle size of 15-5mm, 30 parts of scrap ladle precast block with particle size of 5-0mm, 8 parts of vanadium slag with particle size of 3-1mm, 7 parts of vanadium slag with particle size of 1-0mm, 8 parts of white corundum fine powder with particle size of 200 mesh, 5 parts of magnesia particles with particle size of 1-0mm, 6 parts of magnesia fine powder with particle size of 200 mesh, 4 parts of α-alumina micropowder with particle size of 3μm, 4 parts of α-alumina micropowder with particle size of 1μm, 0.1 part of organic fiber, 2 parts of Nd2O3, 4 parts of cement, 2 parts of steel fiber, and 0.1 part of high-activity alumina.

[0069] The preparation method and sample preparation method of the ladle slag stopping wall castable of the present example are the same as those of Example 1.

[0070] Example 6

[0071] The ladle slag stopping wall castable of the present example is prepared from the following components in mass fraction, which are the same as those of Example 1 except that: 24.8 parts of scrap ladle precast block with particle size of 15-5mm, 24.8 parts of scrap ladle precast block with particle size of 5-0mm, 9.8 parts of vanadium slag with particle size of 3-1mm, 4.9 parts of vanadium slag with particle size of 1-0mm, and 2.1 parts of Nd2O3. That is, the mass ratio of the total mass of scrap ladle precast block and vanadium slag to the mass of Nd2O3 is 30:1.

[0072] The preparation method and sample preparation method of the ladle slag stopping wall castable of the present example are the same as those of Example 1.

[0073] Example 7

[0074] The ladle slag stopping wall castable of the present example is prepared from the following components in mass fraction, which are the same as those of Example 1 except that: 25.2 parts of scrap ladle precast block with particle size of 15-5mm, 25.2 parts of scrap ladle precast block with particle size of 5-0mm, 10.1 parts of vanadium slag with particle size of 3-1mm, 5 parts of vanadium slag with particle size of 1-0mm, and 1 part of Nd2O3. That is, the mass ratio of the total mass of scrap ladle precast block and vanadium slag to the mass of Nd2O3 is 65.5:1.

[0075] The preparation method and sample preparation method of the ladle slag stopping wall castable of the present example are the same as those of Example 1.

[0076] Example 8

[0077] The ladle slag stopping wall castable of the present example has the same mass fractions of the remaining components of the raw materials as in Example 1, except that the mass fractions of the ladle precast block with a particle size of 15-5 mm is 24.5 parts, the ladle precast block with a particle size of 5-0 mm is 24.5 parts, the vanadium slag with a particle size of 3-1 mm is 9.6 parts, the vanadium slag with a particle size of 1-0 mm is 4.8 parts, and Nd2O3 is 3 parts. That is, the mass ratio of the total mass of the ladle precast block and the vanadium slag to the mass of Nd2O3 is 21:1.

[0078] The preparation method and the sample preparation method of the ladle slag stopping wall castable of the present example are the same as in Example 1.

[0079] Example 9

[0080] The ladle slag stopping wall castable of the present example has the same mass fractions of the remaining components of the raw materials as in Example 1, except that the mass fractions of the ladle precast block with a particle size of 15-5 mm is 24.5 parts, the ladle precast block with a particle size of 5-0 mm is 24.5 parts, the vanadium slag with a particle size of 3-1 mm is 9.6 parts, the vanadium slag with a particle size of 1-0 mm is 4.8 parts, and Nd2O3 is 3 parts. That is, the mass ratio of the total mass of the ladle precast block and the vanadium slag to the mass of Nd2O3 is 21:1.

[0081] The preparation method and the sample preparation method of the ladle slag stopping wall castable of the present example are the same as in Example 1.

[0082] Example 10

[0083] The ladle slag stopping wall castable of the present example has the same mass fractions of the remaining components of the raw materials as in Example 1, except that the mass fractions of the ladle precast block with a particle size of 15-5 mm is 24.5 parts, the ladle precast block with a particle size of 5-0 mm is 24.5 parts, the vanadium slag with a particle size of 3-1 mm is 9.6 parts, the vanadium slag with a particle size of 1-0 mm is 4.8 parts, and Nd2O3 is 3 parts. That is, the mass ratio of the total mass of the ladle precast block and the vanadium slag to the mass of Nd2O3 is 21:1.

[0084] The preparation method and the sample preparation method of the ladle slag stopping wall castable of the present example are the same as in Example 1.

[0085] Example 11

[0086] The ladle slag stopping wall castable of the present example has the same mass fractions of the remaining components of the raw materials as in Example 1, except that the mass fractions of the ladle precast block with a particle size of 15-5 mm is 24.5 parts, the ladle precast block with a particle size of 5-0 mm is 24.5 parts, the vanadium slag with a particle size of 3-1 mm is 9.6 parts, the vanadium slag with a particle size of 1-0 mm is 4.8 parts, and Nd2O3 is 3 parts. That is, the mass ratio of the total mass of the ladle precast block and the vanadium slag to the mass of Nd2O3 is 21:1.

[0087] The preparation method and sample preparation method of the continuous casting tundish slag stopping wall castable of the embodiment are the same as those of Embodiment 1.

[0088] Embodiment 12

[0089] The continuous casting tundish slag stopping wall castable of the embodiment has the same mass fractions of the remaining components of the preparation raw materials as those of Embodiment 1, and the difference is that 18 parts of the scrap ladle precast block with a particle size of 15-5 mm, 18 parts of the scrap ladle precast block with a particle size of 5-0 mm, 19.3 parts of the vanadium iron slag with a particle size of 3-1 mm, and 9.7 parts of the vanadium iron slag with a particle size of 1-0 mm are used. That is, the mass ratio of the scrap ladle precast block to the vanadium iron slag is 1.3:1.

[0090] The preparation method and sample preparation method of the continuous casting tundish slag stopping wall castable of the embodiment are the same as those of Embodiment 1.

[0091] Embodiment 13

[0092] The continuous casting tundish slag stopping wall castable of the embodiment has the same mass fractions of the remaining components of the preparation raw materials as those of Embodiment 1, and the difference is that 30 parts of the scrap ladle precast block with a particle size of 15-5 mm, 30 parts of the scrap ladle precast block with a particle size of 5-0 mm, 3.3 parts of the vanadium iron slag with a particle size of 3-1 mm, and 1.7 parts of the vanadium iron slag with a particle size of 1-0 mm are used. That is, the mass ratio of the scrap ladle precast block to the vanadium iron slag is 12:1.

[0093] The preparation method and sample preparation method of the continuous casting tundish slag stopping wall castable of the embodiment are the same as those of Embodiment 1.

[0094] Embodiment 14

[0095] The continuous casting tundish slag stopping wall castable of the embodiment has the same mass fractions of the remaining components of the preparation raw materials as those of Embodiment 1, and the difference is that 12.5 parts of the scrap ladle precast block with a particle size of 15-5 mm, 37.5 parts of the scrap ladle precast block with a particle size of 5-0 mm, 12 parts of the vanadium iron slag with a particle size of 3-1 mm, and 3 parts of the vanadium iron slag with a particle size of 1-0 mm are used. The mass ratio of the scrap ladle precast block with a particle size of 15-5 mm to the scrap ladle precast block with a particle size of 5-0 mm is 1:3. The mass ratio of the vanadium iron slag with a particle size of 3-1 mm to the vanadium iron slag with a particle size of 1-0 mm is 4:1.

[0096] The preparation method and sample preparation method of the continuous casting tundish slag stopping wall castable of the embodiment are the same as those of Embodiment 1.

[0097] Embodiment 15

[0098] The continuous casting tundish slag stopping wall castable of the present example has the same mass fractions of the remaining components of the raw materials as in Example 1, except that 37.5 parts of the scrap ladle preformed block with a particle size of 15-5 mm, 12.5 parts of the scrap ladle preformed block with a particle size of 5-0 mm, 7.5 parts of the vanadium-iron slag with a particle size of 3-1 mm, and 7.5 parts of the vanadium-iron slag with a particle size of 1-0 mm are used. The mass ratio of the scrap ladle preformed block with a particle size of 15-5 mm to the scrap ladle preformed block with a particle size of 5-0 mm is 3:1. The mass ratio of the vanadium-iron slag with a particle size of 3-1 mm to the vanadium-iron slag with a particle size of 1-0 mm is 1:1.

[0099] The preparation method and the sample preparation method of the continuous casting tundish slag stopping wall castable of the present example are the same as in Example 1.

[0100] Example 16

[0101] The continuous casting tundish slag stopping wall castable of the present example has the same mass fractions of the remaining components of the raw materials as in Example 1, except that 10 parts of the scrap ladle preformed block with a particle size of 15-5 mm, 40 parts of the scrap ladle preformed block with a particle size of 5-0 mm, 14 parts of the vanadium-iron slag with a particle size of 3-1 mm, and 1 part of the vanadium-iron slag with a particle size of 1-0 mm are used. The mass ratio of the scrap ladle preformed block with a particle size of 15-5 mm to the scrap ladle preformed block with a particle size of 5-0 mm is 1:4. The mass ratio of the vanadium-iron slag with a particle size of 3-1 mm to the vanadium-iron slag with a particle size of 1-0 mm is 14:1.

[0102] The preparation method and the sample preparation method of the continuous casting tundish slag stopping wall castable of the present example are the same as in Example 1.

[0103] Example 17

[0104] The continuous casting tundish slag stopping wall castable of the present example has the same mass fractions of the remaining components of the raw materials as in Example 1, except that 40 parts of the scrap ladle preformed block with a particle size of 15-5 mm, 10 parts of the scrap ladle preformed block with a particle size of 5-0 mm, 5 parts of the vanadium-iron slag with a particle size of 3-1 mm, and 10 parts of the vanadium-iron slag with a particle size of 1-0 mm are used. The mass ratio of the scrap ladle preformed block with a particle size of 15-5 mm to the scrap ladle preformed block with a particle size of 5-0 mm is 4:1. The mass ratio of the vanadium-iron slag with a particle size of 3-1 mm to the vanadium-iron slag with a particle size of 1-0 mm is 1:2.

[0105] The preparation method and the sample preparation method of the continuous casting tundish slag stopping wall castable of the present example are the same as in Example 1.

[0106] Comparative Example 1

[0107] The continuous casting tundish slag stopping wall castable of the present example has the same mass fractions of the remaining components of the raw materials as in Example 1, except that no Nd2O3 is added.

[0108] The strength and slag penetration resistance of the samples prepared in the above embodiments and comparative examples were determined. The slag penetration resistance test method was as follows: the raw materials were mixed according to the set proportion and particle size distribution, dry-mixed for 5 minutes, then 4.5 wt% water was added and stirred for 5 minutes, followed by vibration casting to form the final product. Cylindrical crucible samples were naturally cured for 24 hours, then demolded and dried in an oven at 110℃ for 24 hours. 80g of intermediate ladle slag (chemical composition of which is shown in Table 1) was added to the crucible sample, and the sample was placed in a furnace at 1550℃ for 3 hours. After removal, the cylindrical crucible sample, eroded by the slag, was cut along its central axis to observe the erosion and penetration of the slag and residue on the crucible. The test results are shown in Table 2.

[0109] As can be seen from the data in Table 2, compared with Comparative Example 1, the strength performance and slag penetration resistance of the continuous casting tundish slag retaining wall castables of each embodiment of the present invention are significantly better than those of Comparative Example 1.

[0110] The contents of each component of the raw materials prepared in Examples 1-5 are different. Among them, Examples 1-3 represent the preferred content range and have better overall performance.

[0111] Compared with Examples 1 and 6-9, the difference lies in the different mass ratios of the total mass of the precast steel ladle blocks and vanadium iron slag to Nd2O3. Among them, the mass ratios of Examples 1, 6, and 7 are within the preferred range, and the strength and slag penetration resistance of the continuous casting tundish slag retaining wall castable are better than those of Examples 8 and 9.

[0112] Compared with Examples 1 and 10-13, the difference lies in the mass ratio of precast scrap steel ladle blocks to vanadium iron slag. Among them, the mass ratio of Examples 1, 10, and 11 is within the preferred range, and the strength performance and slag penetration resistance of the continuous casting tundish slag retaining wall castable are better than those of Examples 12 and 13.

[0113] Compared with Examples 1 and 14-17, the difference lies in the mass ratio of precast scrap steel ladle blocks with a particle size of 15-5mm to those with a particle size of 5-0mm, and the mass ratio of vanadium-iron slag with a particle size of 3-1mm to those with a particle size of vanadium-iron slag of 1-0mm. Among them, the mass ratios of Examples 1, 14, and 15 are within the preferred range, and the strength performance and slag penetration resistance of the continuous casting tundish slag retaining wall castable are better than those of Examples 16 and 17.

[0114] Table 1

[0115]

[0116] Table 2

[0117]

[0118]

[0119] Obviously, the above-mentioned embodiments are only examples for clearly illustrating the present application, and are not intended to limit the present application. Based on the above description, other different forms of changes or variations can be made by those skilled in the art. Here, it is not necessary and also impossible to enumerate all the embodiments. The obvious changes or variations derived from the above description are still within the protection scope of the present application.

Claims

1. A castable for a slag retaining wall in a continuous casting tundish, characterized in that, Its preparation raw materials include the following components in parts by mass: 20-60 parts of precast scrap steel ladles, 15-30 parts of vanadium iron slag, 8-10 parts of fine white corundum powder, 11-20 parts of magnesia, 8-17 parts of α-alumina micro powder, 0.1-1 parts of organic fiber, 1-2 parts of Nd2O3, 3-5 parts of cement, and 0.5-2 parts of steel fiber.

2. The refractory for the slag retaining wall of the continuous casting tundish according to claim 1, characterized in that, Its preparation raw materials include the following components in parts by mass: The composition includes 40-60 parts of precast steel ladle blocks, 15-20 parts of vanadium-iron slag, 8-10 parts of fine white corundum powder, 11-15 parts of magnesia, 8-12 parts of α-alumina micro powder, 0.1-0.5 parts of organic fiber, 1.2-1.8 parts of Nd2O3, 3-5 parts of cement, and 0.8-1.2 parts of steel fiber.

3. The refractory for the slag retaining wall of the continuous casting tundish according to claim 1, characterized in that: The mass ratio of the total mass of precast steel ladle blocks and vanadium iron slag to the mass of Nd2O3 is 30-50:

1.

4. The refractory for the slag retaining wall of the continuous casting tundish according to claim 1, characterized in that: The mass ratio of precast scrap steel ladle blocks to vanadium iron slag is 5–15:

3.

5. The refractory for the slag retaining wall of the continuous casting tundish according to claim 1, characterized in that: The precast scrap steel ladle blocks include precast scrap steel ladle blocks with a particle size of 15-5mm and precast scrap steel ladle blocks with a particle size of 5-0mm; the mass ratio of precast scrap steel ladle blocks with a particle size of 15-5mm to precast scrap steel ladle blocks with a particle size of 5-0mm is 1:0.3 to 3.

6. The refractory for the slag retaining wall of the continuous casting tundish according to claim 1, characterized in that: The vanadium-iron slag includes vanadium-iron slag with a particle size of 3-1 mm and vanadium-iron slag with a particle size of 1-0 mm; the mass ratio of vanadium-iron slag with a particle size of 3-1 mm to vanadium-iron slag with a particle size of 1-0 mm is 1:0.25~1.

7. The refractory for the slag retaining wall of the continuous casting tundish according to claim 1, characterized in that: The particle size of white fused alumina fine powder is 200 mesh; Magnesia includes magnesia particles with a particle size of 1-0 mm and magnesia fine powder with a particle size of 200 mesh; the mass ratio of magnesia particles with a particle size of 1-0 mm to magnesia fine powder with a particle size of 200 mesh is 1:0.6-2. α-Alumina micro powder includes α-alumina micro powder with a particle size of 3 μm and α-alumina micro powder with a particle size of 1 μm; The mass ratio of α-alumina micro powder with a particle size of 3 μm to α-alumina micro powder with a particle size of 1 μm is 1:0.375 to 1.

8.

8. The refractory for the slag retaining wall of the continuous casting tundish according to claim 1, characterized in that: The precast scrap steel ladle blocks contain more than 75 wt% Al2O3, less than 5 wt% CaO, and less than 2 wt% Fe2O3; the water absorption rate of the precast scrap steel ladle blocks is 1%–2%, and the particle density is 2.7–2.9 g / cm³. 3 ; The content of Al2O3 in vanadium-iron slag is 75wt% to 80wt%, the content of MgO is 11wt% to 14wt%, the content of CaO is 2wt% to 85wt%, the content of V2O3 is 1.7wt% to 2.3wt%, and the water absorption rate of vanadium-iron slag is 1.5% to 2%. The content of Al2O3 in the alumina micro powder is greater than 99 wt%; the content of MgO in the magnesia is greater than 95 wt%.

9. The refractory for the slag retaining wall of the continuous casting tundish according to claim 1, characterized in that: The raw materials for its preparation also include 0.1 to 0.5 parts of highly active alumina.

10. A method for preparing a continuous casting tundish slag retaining wall castable as described in any one of claims 1-9, characterized in that, Includes the following steps: The raw materials for preparing the slag retaining wall castable of the continuous casting tundish are mixed and dry-mixed to obtain the slag retaining wall castable of the continuous casting tundish.

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