A ladle lining ceramic welding material and its preparation method and application

Abstract

The present application relates to the technical field of refractory materials, and specifically discloses a ladle lining ceramic welding material, its preparation method, and application. The ladle lining ceramic welding material comprises the following raw materials in parts by weight: 20-80 parts of Al2O3-MgO-CaO particles, 20-80 parts of fused white corundum fine powder, 2-10 parts of fused magnesia, 10-20 parts of defective spinel micropowder, and 2-20 parts of ceramic binder, wherein the ceramic binder comprises 1-20 parts of pure calcium aluminate cement and 1-20 parts of alumina micropowder. The ladle lining ceramic welding material of the present application can be used on the surface of the old lining of the ladle. It has the advantage of not requiring the old lining of the ladle to be removed, further extending the service life of the old ladle and reducing the generation of industrial waste.

Description

Technical Field

[0001] The present application relates to the technical field of refractory materials, and more specifically, to a ladle lining ceramic welding material and a preparation method thereof. Background Art

[0002] In order to meet the needs of ladle turnover, most steel mills use castables or carbon-free prefabricated blocks for the bottom of the ladle, and carbon-free prefabricated blocks or carbon-free machine-pressed bricks for the wall of the ladle. However, regardless of whether prefabricated blocks or carbon-free machine-pressed bricks are used, the life of the ladle is generally not high, and the production cycle is generally long, which will affect the fast-paced production of the steel mill. At the same time, remaking the ladle will also generate a large amount of industrial waste.

[0003] At present, after the steel ladles of relevant steel enterprises have reached a certain lifespan, the remaining working lining bricks will be removed and new working lining will be rebuilt. This will generate a large amount of new industrial waste and cause waste of resources. Summary of the Invention

[0004] In order to extend the service life of a ladle and reduce the generation of industrial waste, the present application provides a ladle lining ceramic welding material and a preparation method thereof.

[0005] The present application provides a ladle lining ceramic welding material and its preparation method and application adopt the following technical solutions: In the first aspect, the present application provides a ladle lining ceramic welding material, which adopts the following technical solutions:

[0006] A ladle lining ceramic welding material comprises the following raw materials in parts by weight:

[0007] 20-80 parts of Al2O3-MgO-CaO particles, 20-80 parts of fused white corundum fine powder, 2-10 parts of fused magnesia, 10-20 parts of defective spinel powder and 2-20 parts of ceramic binder, wherein the ceramic binder includes 1-10 parts of pure calcium aluminate cement and 1-10 parts of alumina powder.

[0008] By adopting the above technical solution, Al2O3-MgO-CaO particles, fused white corundum fine powder, fused magnesia, and modified defective spinel powder are used as the main raw materials of welding materials, and pure calcium aluminate cement and alumina fine powder are added as ceramic binders. After blending, the mixture is sprayed onto the old lining of the ladle. In addition, the high temperature environment when the ladle is in use is utilized to achieve a tight bond between the new and old working linings, thereby achieving the effect of extending the service life of the ladle and reducing the generation of industrial waste caused by the dismantling of the old working ladle.

[0009] The addition of Al2O3-MgO-CaO particles, on the one hand, can undergo flexible deformation in the high temperature environment of the ladle, relieve internal stress, reduce stress damage, and thus improve the thermal shock resistance of the welding material; on the other hand, the Al2O3-MgO-CaO particles can produce a high-viscosity slag layer on their surface at high temperatures, inhibiting slag penetration, reducing material deterioration and damage, and promoting the densification of the matrix of the welding material at high temperatures, thereby improving the material's corrosion resistance.

[0010] Defective spinel dissolves Al2O3 at high temperature, forming a "spinel-CA6-corundum" composite structure on the surface adjacent to the spinel. This structure is different from the spinel-CA6-corundum formed by ordinary spinel at this temperature. At the same time, since the main mineral phase does not contain periclase phase, the structure is more stable at high temperature, which improves the thermal shock resistance of the welding material. In addition, the defective spinel will expand slightly in the high temperature environment when the ladle is used, with a volume expansion rate of about 8%, thereby reducing the occurrence of cracks in the ladle lining, improving the corrosion resistance of the ladle lining, and further extending the service life of the ladle.

[0011] Preferably, the defective spinel powder is a modified defective spinel powder, and the preparation method of the modified defective spinel powder comprises the following steps:

[0012] The defective spinel powder is ultrasonically dispersed in an ethanol solution, and then microcrystalline wax is added and mixed, and the mixture is heated to 45-55° C. and kept warm for 1-2 hours. The weight ratio of the defective spinel powder to the microcrystalline wax is 1:(1-2). The modified defective spinel powder is filtered and dried.

[0013] By adopting the above technical solution, microcrystalline wax is added to wrap the defective spinel powder. The microcrystalline wax has not completely melted at a temperature of 45-55°C, but the surface of the microcrystalline wax will soften at this temperature, allowing the microcrystalline wax to combine with the defective spinel powder. In addition, since the microcrystalline wax contains many long-chain and cyclic saturated hydrocarbons in addition to normal alkanes and isoalkanes, the microcrystalline wax has a higher viscosity after melting and is not easy to break.

[0014] When the welding material is mixed with water and sprayed onto the surface of the old lining of the ladle, the pure calcium aluminate cement reacts with the water to form a hydration reaction and works together with other ceramic binders to bond the other raw materials of the welding material to the old lining of the ladle. Since the surface of the old lining of the ladle is mostly rough and uneven after a long period of use, when the welding material is combined with the old lining of the ladle by spraying, the microcrystalline wax is softened by the hydration temperature of the pure calcium aluminate cement, which helps to better penetrate into the rough pores on the surface of the old lining of the ladle, thereby enhancing the bonding effect between the welding material and the surface of the old lining of the ladle; when the ladle is put into use, the defective spinel will expand slightly under high temperature conditions, squeezing the microcrystalline wax, reducing stress damage to the welding material, improving the thermal shock resistance of the welding material, and extending the service life of the ladle lining.

[0015] Preferably, polyacrylic acid resin is further added during the process of modifying the defective spinel powder, and the weight ratio of the defective spinel powder to the polyacrylic acid resin is 1:(0.5-1). The preparation method comprises the following steps:

[0016] The defective spinel micropowder is ultrasonically dispersed in an ethanol solution, and then microcrystalline wax is added and mixed. The solution is heated to 45-55°C and kept warm for 1-2 hours. The weight ratio of the defective spinel micropowder to the microcrystalline wax is 1:(1-2). After filtration and drying, polyacrylic acid resin powder is added and mixed to finally obtain modified defective spinel micropowder.

[0017] By adopting the above technical solution, polyacrylic resin is wrapped on the outside of microcrystalline wax and defective spinel, and the microcrystalline wax plays the role of bonding the polyacrylic resin and the defective spinel. On the one hand, the problem of defective spinel powder easily agglomerating due to the presence of microcrystalline wax is reduced, and the dispersibility of the defective spinel powder is improved; on the other hand, when the welding material is sprayed onto the surface of the ladle lining, the polyacrylic resin swells when it comes into contact with water, and is embedded in the pore structure of the surface of the ladle lining through expansion, thereby enhancing the initial bonding effect between the welding material and the old lining of the ladle, and reducing the displacement of the spraying material after the spraying is completed.

[0018] Preferably, the particle size of the polyacrylic acid resin powder is 20-30 nanometers.

[0019] By adopting the above technical solution, when the particle size of the polyacrylic acid resin powder is within this range, the agglomeration of the modified defective spinel micropowder can be reduced. At the same time, it can ensure that the polyacrylic acid resin powder can smoothly enter the pores of the ladle lining, and the polyacrylic acid resin powder will swell slightly after absorbing water, so that it can play the effect of being stuck in the pore structure of the ladle lining, further enhancing the bonding strength between the welding material and the ladle lining.

[0020] Preferably, 10-20 parts of isopropyl alcohol is also included.

[0021] By adopting the above technical solution, since the main raw materials of the welding material are mostly inorganic substances, and the old lining of the ladle also has a rough surface formed by inorganic substances, the addition of isopropyl alcohol can enhance the permeability of the welding material and reduce the unevenness of the welding material sprayed on the ladle lining due to agglomeration. Moreover, after the welding material is sprayed on the ladle lining, the isopropyl alcohol promotes the rapid volatilization of water, thereby achieving the effect of rapid drying of the welding material. The polyacrylic resin powder and the ceramic binder can quickly bond to the ladle in the early stage, providing a stabilizing effect for the subsequent bonding of the welding material and the ladle lining. When the ladle is put into use, the ceramic binder plays a major bonding role, thereby reducing the situation where the welding material falls off the ladle.

[0022] Preferably, the vitrified binder further comprises 1-10 parts of calcium aluminate titanate fine powder.

[0023] By adopting the above technical solution, during the use of the ladle, the high temperature environment of the ladle itself is utilized, and the fine calcium aluminate powder promotes the sintering of alumina and fused magnesia, thereby connecting the welding material with the old working lining of the ladle.

[0024] In a second aspect, the present application provides a method for preparing a ceramic welding material, which adopts the following technical solution:

[0025] A method for preparing a ceramic welding material comprises the following steps:

[0026] Al2O3-MgO-CaO particles, fused white corundum fine powder, fused magnesia, and defective spinel fine powder are mixed, and then ceramic binder and isopropyl alcohol are added and mixed to prepare welding materials.

[0027] By adopting the above technical solution, the welding material made from the above raw materials can have a good bonding effect with the old lining of the ladle and is not easy to fall off, thereby improving the service life of the ladle lining.

[0028] In a third aspect, the present application provides an application of a ceramic welding material, using the following technical solution:

[0029] A ceramic welding material is applied. The raw materials of the welding material are mixed evenly with water in a weight ratio of 10:(1-1.2), and then sprayed onto the surface of the old residual lining of a ladle to form a new working lining. The sum of the thickness of the sprayed layer and the thickness of the residual working lining does not exceed the thickness of the original working lining.

[0030] By adopting the above technical solution, the above welding material is mixed with water and then sprayed onto the old lining of the ladle at room temperature. There is no need to remove the old lining of the ladle, which further extends the service life of the old ladle and reduces the generation of industrial waste.

[0031] In summary, this application has the following beneficial effects:

[0032] 1. Since the present application adopts Al2O3-MgO-CaO particles, the addition of Al2O3-MgO-CaO particles can, on the one hand, undergo flexible deformation in the high temperature environment of the ladle, relieve internal stress, reduce stress damage, and thus improve the thermal shock resistance of the welding material; on the other hand, the Al2O3-MgO-CaO particles can produce a high-viscosity slag layer on their surface at high temperatures, inhibiting slag penetration, reducing material deterioration and damage, and promoting matrix densification of the welding material at high temperatures, thereby improving the corrosion resistance of the material.

[0033] 2. Defective spinel is preferably used in this application. Defective spinel will expand slightly under the high temperature environment when the ladle is used, and the volume expansion rate is about 8%, thereby reducing the occurrence of cracks in the ladle lining, improving the corrosion resistance of the ladle lining, and further extending the service life of the ladle.

[0034] 3. The application of the ceramic welding material of the present application is to mix the raw materials of the welding material with water in a weight ratio of 10: (1-1.2) and then spray it onto the surface of the old residual lining of the ladle to form a new working lining. The new lining is sprayed onto the old lining of the ladle at room temperature. There is no need to remove the old lining of the ladle, which further extends the service life of the old ladle and reduces the generation of industrial waste. DETAILED DESCRIPTION

[0035] Source of raw materials:

[0036] All raw materials in the examples and comparative examples of the present application are commercially available. The following sources of raw materials are disclosed only for the purpose of full disclosure and should not limit the scope of protection.

[0037] Al2O3-MgO-CaO particles, particle size 1-3mm, main chemical components: Al2O3: 60-70%, MgO: 25-30%; CaO: 5-10%, main mineral phase composition is spinel, CA, CA2, physical properties: bulk density 2.2-2.4g / cm 3 , apparent porosity is 24-32%, D50 = 2 microns;

[0038] Defective spinel micropowder, main characteristics: bimodal particle size distribution, fine grains, uniform distribution; main mineral phases: corundum phase, defective spinel phase, no periclase phase; chemical composition: Al2O3: 70-92%, MgO: 8-28%;

[0039] The particle size grade of fused white corundum fine powder is 0-0.04mm;

[0040] The fused magnesia includes 0-60% of the particle size of 1-3mm, 0-60% of the particle size of 0.075-1mm, and 0-60% of the fine powder of 0-0.075mm. The total amount of the fused magnesia of various particle sizes is 100%.

[0041] Pure calcium aluminate cement CAS number: 65997-16-2;

[0042] Alumina powder, Al2O3 content is 99.8%, particle size is 3 microns;

[0043] The particle size of calcium aluminate titanate fine powder is 0-0.074mm;

[0044] Microcrystalline wax CAS: 8001-75-0, average particle size 15nm;

[0045] Polyacrylic acid resin CAS: 24938-16-7;

[0046] Isopropyl alcohol CAS: 67-63-0, molecular weight: 60.09502;

[0047] The sintering temperature of fused spinel powder is 1400-1600℃.

[0048] Example

[0049] Examples 1.1-1.3

[0050] A ladle lining ceramic welding material, comprising the following raw materials by weight:

[0051] 20-80kg of Al2O3-MgO-CaO particles, 20-80kg of fused white corundum fine powder, 2-10kg of fused magnesia, 10-20kg of defective spinel fine powder and 2-20kg of ceramic binder, wherein the ceramic binder includes 1-10kg of pure calcium aluminate cement, 1-10kg of alumina fine powder and 1-10kg of calcium aluminate titanate fine powder.

[0052] The raw material amounts of the ceramic welding materials in Examples 1.1-1.3 are shown in Table 1.

[0053] Table 1 Raw material dosage of ceramic welding materials of Examples 1.1-1.3 (unit: kg)

[0054]

[0055] A preparation method of a ladle lining ceramic welding material comprises the following steps: placing Al2O3-MgO-CaO particles, fused white corundum fine powder, fused magnesia, and defective spinel fine powder into a mixer for uniform mixing, and then adding a ceramic binder to prepare the welding material.

[0056] Example 2

[0057] A ladle lining ceramic welding material, which differs from Example 1.2 in that an equal amount of modified defect spinel micropowder is used to replace the unmodified defect spinel micropowder, and the modification method of the modified defect spinel micropowder comprises the following steps:

[0058] The defective spinel micropowder is ultrasonically dispersed in an ethanol solution, the mass ratio of the defective spinel micropowder to the ethanol solution is 1:3, and then microcrystalline wax is added and mixed. The mixture is heated to 55°C and kept warm for 2 hours. The weight ratio of the defective spinel micropowder to the microcrystalline wax is 1:1.5. After filtration and drying, modified defective spinel micropowder with an average particle size of 4 microns is obtained.

[0059] Example 3

[0060] A ladle lining ceramic welding material differs from Example 2 in that, during the modification process of defective spinel micropowder, an equal amount of paraffin wax is used to replace microcrystalline wax.

[0061] Example 4

[0062] A ladle lining ceramic welding material, which differs from Example 2 in that polyacrylic acid resin powder with a particle size of 25 nanometers is added to the modified spinel, and the modification method thereof comprises the following steps:

[0063] 1 kg of defective spinel micropowder was ultrasonically dispersed in an ethanol solution, with the mass ratio of defective spinel micropowder to ethanol solution being 1:3. Microcrystalline wax was then added and mixed, and the mixture was heated to 55°C and kept warm for 2 hours. The weight ratio of defective spinel micropowder to microcrystalline wax was 1:1.5. After filtration and drying, polyacrylic acid resin powder was added and mixed for 30 minutes to finally obtain modified defective spinel micropowder with an average particle size of 4 microns.

[0064] Examples 5.1-5.4

[0065] A ladle lining ceramic welding material is different from Example 4 in that the particle size of the polyacrylic acid resin powder is different.

[0066] The particle size of the polyacrylic acid resin powder added in Example 5.1 is 20 nanometers;

[0067] The particle size of the polyacrylic acid resin powder added in Example 5.2 is 30 nanometers;

[0068] The particle size of the polyacrylic acid resin powder added in Example 5.3 is 10 nm;

[0069] The particle size of the polyacrylic acid resin powder added in Example 5.4 is 40 nanometers.

[0070] Examples 6.1-6.3

[0071] A ladle lining ceramic welding material, which differs from Example 4 in that 10-20 kg of isopropyl alcohol is further added to the welding material. The preparation method of the ladle lining ceramic welding material comprises the following steps: Al2O3-MgO-CaO particles, fused white corundum fine powder, fused magnesia, and defective spinel fine powder are mixed, and then a ceramic binder and isopropyl alcohol are added and mixed to form the welding material.

[0072] The amount of isopropyl alcohol added in Example 6.1 is 10 kg;

[0073] The amount of isopropyl alcohol added in Example 6.2 was 15 kg;

[0074] The amount of isopropanol added in Example 6.3 is 20 kg.

[0075] Example 7

[0076] A ladle lining ceramic welding material differs from Example 4 in that isopropanol is replaced by an equal amount of ethanol.

[0077] Example 8

[0078] A ladle lining ceramic welding material, which is different from Example 1.2 in that the amount of calcium aluminate titanate fine powder in the ceramic binder is 0 kg.

[0079] Comparative Example

[0080] Comparative Example 1

[0081] A ladle lining ceramic welding material, which is different from Example 1.2 in that the amount of Al2O3-MgO-CaO particles used is 0 kg.

[0082] Comparative Example 2

[0083] A ladle lining ceramic welding material differs from Example 1.2 in that an equal amount of sintered corundum is used to replace Al2O3-MgO-CaO series particles.

[0084] Comparative Example 3

[0085] A ladle lining ceramic welding material, which is different from Example 1.2 in that the amount of defective spinel powder used is 0 kg.

[0086] Comparative Example 4

[0087] A ladle lining ceramic welding material, which differs from Example 1.2 in that an equal amount of fused spinel powder is used to replace the defective spinel powder.

[0088] Application Examples

[0089] Application Examples 1.1-1.3

[0090] An application of a ceramic welding material for a ladle lining comprises uniformly mixing the welding materials of Examples 1.1 to 1.3 with water in a weight ratio of 10:1.1, and then uniformly spraying the ceramic welding material for the ladle lining onto the surface of the old ladle lining using a gunning machine, wherein the sum of the thickness of the gunning layer and the thickness of the remaining working lining does not exceed the thickness of the original working lining.

[0091] Application Examples 2-4

[0092] An application of a ladle lining ceramic welding material is based on Application Example 1.2, and the welding material is prepared in accordance with Examples 2-4 in sequence.

[0093] Application Example 5.1-Application Example 5.4

[0094] An application of a ladle lining ceramic welding material is based on Application Example 4, and the welding material is prepared by Examples 5.1-5.4.

[0095] Application Examples 6.1-6.3

[0096] An application of a ladle lining ceramic welding material is based on Application Example 4, and the welding material is prepared by Examples 6.1-6.3.

[0097] Application Examples 7-8

[0098] An application of a ladle lining ceramic welding material is provided. Based on Application Example 4, the welding material is prepared in sequence according to Examples 7-8.

[0099] Comparative Application Examples 1-4

[0100] An application of a ladle lining ceramic welding material is based on Application Example 1.2, and the welding material is prepared in sequence from Comparative Examples 1-4.

[0101] Performance testing

[0102] The tests include:

[0103] 1. Compressive strength and bulk density test

[0104] The ladle linings prepared in Application Examples 1.1-1.3, Application Examples 2-4, Application Examples 5.1-5.4, Application Examples 6.1-6.3, Application Examples 7-8, and Comparative Application Examples 1-4 were subjected to compressive strength tests. The test method is as follows:

[0105] Old ladle linings of the same size and thickness were used to create test specimens measuring 100*100*140mm. Welding material was sprayed onto the surfaces of the old ladle linings to a thickness of 30mm, forming new working linings with a total thickness of 170mm. The new ladle linings were sintered at 1600°C and tested for compressive strength and bulk density using the methods specified in GB / T5072-2008, "Test Method for Compressive Strength of Refractory Materials at Room Temperature," and GB / T2997-2015, "Test Method for Bulk Density, Apparent Porosity, and True Porosity of Dense Shaped Refractory Products."

[0106] The higher the compressive strength, the better the bonding strength between the welding material and the old lining of the ladle. The greater the volume density, the denser the ladle lining formed at high temperature and the stronger the corrosion resistance.

[0107] The test results are shown in Table 2.

[0108] Table 2 Compressive strength and bulk density test results

[0109]

[0110]

[0111] Combining application examples 1.1-1.3 and comparative application examples 1-4 and Table 2, it can be seen that the compressive strength and volume density of the ladle lining of application examples 1.1-1.3 are better than those of comparative application examples 1-4, indicating that the defective spinel micropowder used in this application has better bonding strength than the fused spinel, and can have better thermal shock resistance at high temperatures. This is because the defective spinel micropowder has stronger reactivity, and the reaction temperature of the defective spinel micropowder is lower than that of the fused spinel micropowder, which can promote the sintering of the welding material at high temperature and make the reaction more complete. At the same time, the micro-expansion of the defective spinel at high temperature is utilized to help form a sintered and dense ladle lining, thereby extending the service life of the ladle lining.

[0112] In addition, Application Examples 1.1-1.3 are all better than Comparative Example 4, indicating that the addition of Al2O3-MgO-CaO particles has the following effects compared with sintered corundum: on the one hand, in the high temperature environment of the ladle, the Al2O3-MgO-CaO particles can undergo flexible deformation, relieve internal stress, reduce stress damage, and thus improve the thermal shock resistance of the welding material; on the other hand, at high temperatures, the Al2O3-MgO-CaO particles can produce a high-viscosity slag layer on their surface, which inhibits slag penetration, reduces material deterioration and damage, and promotes matrix densification of the welding material at high temperatures, thereby improving the material's corrosion resistance and helping to increase the service life of the ladle lining.

[0113] Combining Application Example 1.2 and Application Example 2-3 and Table 2, it can be seen that the compressive strength and bulk density of Application Example 2-3 are better than those of Application Example 1.2, indicating that the addition of the modified defective spinel allows the welding material to be combined with the old lining of the ladle by spraying. The microcrystalline wax is softened by the hydration temperature of the pure calcium aluminate cement, which helps to better penetrate into the rough pores on the surface of the old lining of the ladle, thereby enhancing the bonding effect between the welding material and the surface of the old lining of the ladle; when the ladle is put into use, the defective spinel will expand slightly in a high temperature environment, squeezing the microcrystalline wax, reducing the stress damage of the welding material, improving the thermal shock resistance of the welding material, and extending the service life of the ladle lining.

[0114] Combining Application Example 2 and Application Example 4 and Table 2, it can be seen that Application Example 4 is better than Application Example 2, indicating that sodium polyacrylate resin powder is added in this application, and the polyacrylate resin powder is wrapped on the outside of the microcrystalline wax and the defective spinel. The microcrystalline wax plays a role in bonding the polyacrylate resin and the defective spinel. On the one hand, the problem of defective spinel powder easily agglomerating due to the presence of microcrystalline wax is reduced, and the dispersibility of the defective spinel powder is improved; on the other hand, when the welding material is sprayed onto the surface of the ladle lining, the polyacrylate resin swells when it comes into contact with water, and is embedded in the pore structure of the ladle lining surface through expansion, thereby enhancing the initial bonding effect between the welding material and the old lining of the ladle, reducing the displacement of the spraying material after the spraying is completed, and thus ensuring the bonding strength between the welding material and the old lining of the ladle.

[0115] Combining Application Example 4 and Application Examples 5.1-5.4 and Table 2, it can be seen that there is no substantial difference in the experimental results of Application Example 4 and Application Examples 5.1-5.2, and Application Examples 4 and Application Examples 5.1-5.2 are both better than Application Examples 5.3-5.4, indicating that when the particle size of the polyacrylic acid resin powder added in this application is 20-30 nanometers, it can reduce the agglomeration of the modified defective spinel micropowder. At the same time, it can ensure that the polyacrylic acid resin powder smoothly enters the pores of the ladle lining, and the polyacrylic acid resin powder swells slightly after absorbing water, so that it can play the effect of being stuck in the pore structure of the ladle lining, further enhancing the bonding strength between the welding material and the ladle lining; when the particle size of the polyacrylic acid resin powder is too small (i.e., Application Example 5.3), agglomeration is likely to occur, and when the particle size is too large (i.e., Application Example 5.4), it is not conducive to the modified defective spinel powder entering the pores of the ladle lining, which is not conducive to the bonding strength between the two.

[0116] Combining Application Examples 6.1-6.3, Application Example 4 and Application Example 7 and Table 2, it can be seen that Application Examples 6.1-6.3 are better than Application Examples 4 and Application Example 7, indicating that isopropyl alcohol is added in this application because the main raw materials of the welding materials are mostly inorganic substances, and the old lining of the ladle also has a rough surface formed by inorganic substances. The addition of isopropyl alcohol can enhance the permeability of the welding material and reduce the uneven spraying of the welding material on the ladle lining due to agglomeration. After the welding material is sprayed on the ladle lining, isopropyl alcohol promotes rapid volatilization of water, thereby achieving the effect of rapid drying of the welding material. The polyacrylic resin powder and the ceramic binder can quickly bond to the ladle in the early stage, providing a stabilizing effect for the later bonding of the welding material and the ladle lining. When the ladle is put into use, the ceramic binder plays a major bonding role, reducing the situation where the welding material falls off from the old lining of the ladle.

[0117] Combining Application Example 1.2 and Application Example 8 with Table 2, it can be seen that during the use of the ladle, the high temperature environment of the ladle itself is utilized, and the fine calcium aluminate powder promotes the sintering of alumina and fused magnesia, thereby connecting the welding material with the old working lining of the ladle, thereby improving the bonding strength.

[0118] The tests include:

[0119] 2. Ladle lining service life test

[0120] The ladle lining made of the welding materials of Application Example 1.2, Application Example 2-4, Application Example 6.2 and Comparative Application Example 1-4 was applied to the actual production of the ladle converter. The average spraying thickness of the welding material was 30 mm. After the ladle circulated the molten steel 30 times, the thickness difference of the ladle working lining was tested.

[0121] Thickness difference of working lining = average thickness of ladle working lining after 30 uses - average thickness of ladle working lining at the beginning.

[0122] The smaller the thickness difference of the working lining, the longer the service life of the ladle. When the thickness difference of the working lining is greater than 25mm, it means that the service life of the ladle is approaching and it is not suitable to perform molten steel turnover work on it.

[0123] The test results are as shown in 3.

[0124] Table 3 Ladle lining service life test results

[0125]

[0126]

[0127] Combining Application Example 1.2 with Comparative Application Examples 1-4 and Table 3, it can be seen that the working lining thickness difference of Application Example 1.2 is smaller, and the addition of defective spinel micropowder and Al2O3-MgO-CaO particles helps to extend the thermal shock resistance and corrosion resistance of the welding material, thereby extending the service life of the ladle working lining.

[0128] Combining Application Example 1.2 and Application Example 2-3 and Table 3, it can be seen that Application Example 2 is better than Application Example 1.2 and Application Example 3. The present application can further improve the bonding strength between the welding material and the old lining of the ladle by adding the modified defective spinel powder. Compared with paraffin wax (i.e., Application Example 3), the addition of microcrystalline wax has a higher viscosity after melting and is not easy to break because microcrystalline wax contains many long-chain and cyclic saturated hydrocarbons in addition to normal alkanes and isoalkanes.

[0129] Combining Application Example 4 and Application Example 2 and Table 3, it can be seen that the service life of Application Example 4 is longer than that of Application Example 2. This is because polyacrylic resin powder is added in the process of modifying the defective spinel, and the polyacrylic resin is wrapped on the outside of the microcrystalline wax and the defective spinel. The microcrystalline wax plays a role in bonding the polyacrylic resin and the defective spinel. When the welding material is sprayed onto the surface of the ladle lining, the polyacrylic resin swells when it comes into contact with water, and is embedded in the pore structure of the ladle lining surface through expansion, thereby enhancing the initial bonding effect between the welding material and the old lining of the ladle, reducing the displacement of the spraying material after the spraying is completed, and improving the bonding strength between the two, which helps to extend the service life of the ladle lining.

[0130] Combining Application Example 4 and Application Example 6.2 with Table 3, it can be seen that Application Example 6.2 is better than Application Example 4, indicating that the addition of isopropyl alcohol in this application can enhance the permeability of the welding material and reduce the uneven spraying of the welding material onto the ladle lining due to agglomeration. After the welding material is sprayed onto the ladle lining, isopropyl alcohol promotes the rapid volatilization of water, thereby achieving the effect of rapid drying of the welding material. The polyacrylic resin powder and the ceramic binder can quickly bond to the ladle in the initial stage, providing a stabilizing effect for the later bonding of the welding material and the ladle lining, thereby extending the service life of the ladle.

[0131] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed, but as long as they are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A ladle lining ceramic welding material, characterized in that: The composition comprises the following raw materials in parts by weight: 20-80 parts of Al2O3-MgO-CaO particles, 20-80 parts of fused white corundum fine powder, 2-10 parts of fused magnesia, 10-20 parts of defective spinel fine powder, 2-20 parts of vitrified binder, and 10-20 parts of isopropyl alcohol, wherein the vitrified binder comprises 1-10 parts of pure calcium aluminate cement, 1-10 parts of alumina fine powder, and 1-10 parts of calcium aluminate titanate fine powder; The defective spinel powder is a modified defective spinel powder, and the preparation method of the modified defective spinel powder comprises the following steps: The defective spinel micropowder is ultrasonically dispersed in an ethanol solution, and then microcrystalline wax is added and mixed. The solution is heated to 45-55° C. and kept warm for 1-2 hours. The weight ratio of the defective spinel micropowder to the microcrystalline wax is 1:(1-2). After filtration and drying, polyacrylic acid resin powder is added and mixed. The weight ratio of the defective spinel micropowder to the polyacrylic acid resin powder is 1:(0.5-1). Finally, modified defective spinel micropowder is obtained.

2. The ladle lining ceramic welding material according to claim 1, characterized in that: The particle size of the polyacrylic acid resin powder is 20-30 nanometers.

3. A method for preparing the ceramic welding material according to claim 1 or 2, characterized in that: The following steps are involved: Al2O3-MgO-CaO particles, fused white corundum fine powder, fused magnesia, and defective spinel fine powder are mixed, and then ceramic binder and isopropyl alcohol are added and mixed to prepare welding materials.

4. Use of the ceramic welding material according to claim 1 or 2, characterized in that: The raw materials of the welding material are evenly mixed with water in a weight ratio of 10:(1-1.2), and then sprayed onto the surface of the old residual lining of the ladle to form a new working lining. The sum of the thickness of the sprayed layer and the thickness of the residual lining of the working lining does not exceed the thickness of the original working lining.

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