Fire-resistant crucible capable of withstanding multiple high-temperature thermal shocks and method of making same

Abstract

The application discloses a fire-resistant crucible capable of resisting multiple high-temperature thermal shocks and a preparation method thereof, and belongs to the technical field of refractory materials. The fire-resistant crucible comprises a body, and the body comprises the following components in parts by weight based on the total weight of raw materials: 8-12 parts of a liquid carrier, 70-85 parts of corundum aggregate, 5-12 parts of aluminum oxide powder, 3-10 parts of silicon dioxide powder, 0.3-1 part of yttrium trioxide powder and 3-8 parts of zirconium silicate powder. After high-temperature sintering, a "mullite phase-intermittent high-alumina glass phase-tetragonal zirconium dioxide dispersed particle" composite grain boundary phase is formed, the corundum aggregate forms a continuous three-dimensional network structure and serves as a framework of the "mullite phase-intermittent high-alumina glass phase-tetragonal zirconium dioxide dispersed particle" composite grain boundary phase. The liquid carrier is removed by volatilization. The fire-resistant crucible capable of resisting multiple high-temperature thermal shocks has excellent high-temperature strength and can resist multiple high-temperature thermal shocks.

Description

Technical Field

[0001] This invention relates to the field of refractory materials technology, and in particular to a refractory crucible capable of withstanding repeated high-temperature thermal shock and its preparation method. Background Technology

[0002] Currently, with the development of aerospace metallurgical materials, the demand for smelting refractory metals, special alloys, and ultrapure metals is increasing, which places higher demands on the thermal shock stability, corrosion resistance, spalling resistance, and high-temperature strength of alumina crucibles, which are the basic smelting tools for special alloys.

[0003] However, existing alumina crucibles struggle to balance high-temperature strength and thermal shock resistance in practical applications. Their strength significantly decreases at temperatures above 1500℃. Furthermore, alumina crucibles undergo multiple heating and cooling cycles during metal smelting, resulting in severe thermal shocks that cause cracking, spalling, and short service life. Additionally, while existing toughening methods provide some toughening at room temperature, the crucibles soften at high temperatures, severely weakening their high-temperature strength. Therefore, there is an urgent need for a refractory crucible that possesses excellent high-temperature strength and can withstand repeated high-temperature thermal shocks. Summary of the Invention

[0004] The purpose of this invention is to overcome at least one deficiency of the prior art and provide a refractory crucible that has excellent high-temperature strength and can withstand repeated high-temperature thermal shocks; in addition, it also provides a method for preparing a refractory crucible that can withstand repeated high-temperature thermal shocks.

[0005] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: According to one aspect of this application, a refractory crucible capable of withstanding repeated high-temperature thermal shock is provided, comprising: The body has a receiving cavity with one open end. The body comprises the following components by weight, based on the total weight of the raw materials: The composition comprises 8-12 parts liquid carrier, 70-85 parts corundum aggregate, 5-12 parts alumina powder, 3-10 parts silica powder, 0.3-1 parts yttrium oxide powder, and 3-8 parts zirconium silicate powder. After high-temperature sintering, 4-10 parts of the alumina powder and 2-9 parts of the silica powder undergo a solid-phase diffusion reaction at high temperature to form a mullite phase in situ. The remaining unreacted alumina powder and the remaining unreacted silica powder melt at high temperature to form an aluminosilicate liquid phase, which then cools to form a high-alumina glass phase. 0.2-0.9 parts of the yttrium oxide powder react with the remaining silica powder at a temperature below a certain high temperature to form yttrium pyrosilicate. 3-8 parts of the zirconium silicate powder decompose at temperatures above 1540℃ to form silica and monoclinic zirconium dioxide. The decomposed monoclinic zirconium dioxide... Zirconium undergoes a phase transformation above 1170℃ to form tetragonal zirconia dispersed at grain boundaries. This dispersed tetragonal zirconia causes the remaining alumina powder to separate from the high-alumina glass phase formed by the decomposition of silica at high temperatures and the high-alumina glass phase formed after cooling, forming a discontinuous high-alumina glass phase. The remaining yttrium oxide powder maintains the stability of the tetragonal zirconia at temperatures greater than or equal to 1170℃, forming a composite grain boundary phase of "mullite phase - discontinuous high-alumina glass phase - tetragonal zirconia dispersed particles." The corundum aggregate forms a continuous three-dimensional network structure and serves as the framework for the formed composite grain boundary phase of "mullite phase - discontinuous high-alumina glass phase - tetragonal zirconia dispersed particles." The generated yttrium pyrosilicate lowers the nucleation barrier of the mullite phase, and the liquid carrier evaporates and removes it. Alternatively, after high-temperature sintering, 4-10 parts of the alumina powder and 2-9 parts of the silica powder undergo a solid-phase diffusion reaction at high temperature to form a mullite phase in situ. The remaining unreacted alumina powder and the remaining unreacted silica powder melt at high temperature to form an aluminosilicate liquid phase, which then forms a high-alumina glass phase after cooling. 0.3-1 parts of the yttrium oxide powder react with the remaining silica powder at a temperature below a certain high temperature to form yttrium pyrosilicate. 3-8 parts of the zirconium silicate powder form dispersed zirconium silicate particles at the grain boundaries between 1170-1540℃. The dispersed zirconium silicate particles at the grain boundaries cause the remaining alumina powder to separate from the high-alumina glass phase formed by the decomposition of silica at high temperature and the high-alumina glass phase formed after cooling, forming a discontinuous high-alumina glass phase, thus forming a "mullite phase-discontinuous high-alumina glass phase-zirconia silicate dispersed particles" composite grain boundary phase. The corundum aggregate forms a continuous three-dimensional network structure and serves as the framework for the formed "mullite phase-discontinuous high-alumina glass phase-zirconia silicate dispersed particles" composite grain boundary phase. The generated yttrium pyrosilicate can reduce the nucleation barrier of the mullite phase, and the liquid carrier evaporates and removes it.

[0006] The beneficial effects of this invention are as follows: The raw materials of the main body in this embodiment include appropriate amounts of liquid carrier, corundum aggregate, alumina powder, silica powder, yttrium oxide powder, and zirconium silicate powder, which facilitates the mixing of each powder with the liquid carrier to obtain a mixed slurry. This facilitates the use of the mixed slurry to form a crucible green body, which is then sintered to form a refractory crucible. Furthermore, by adding appropriate amounts of alumina powder and silica powder, during the sintering of the crucible green body to form a refractory crucible, the alumina powder and silica powder react in situ at high temperature to generate a mullite phase. The remaining unreacted alumina powder and the remaining unreacted silica powder melt at high temperature to form an aluminosilicate liquid phase. After the aluminosilicate liquid phase cools, a high-alumina glass phase forms, generating a mullite phase that transforms the continuous glass phase into a composite grain boundary phase of "mullite whiskers-discontinuous high-alumina glass phase." The mullite phase, with its whisker morphology, acts as grain boundary pinning, significantly improving the high-temperature strength of the bulk material, thereby enhancing the high-temperature strength of the refractory crucible. Furthermore, the alumina powder and silica powder that did not undergo the high-temperature reaction to form a mullite phase in situ form a residual high-alumina glass phase. This residual high-alumina glass phase exhibits viscous flow characteristics at high temperatures, which can relax thermal stress and improve the thermal shock resistance of the bulk material, thus enhancing the thermal shock resistance of the refractory crucible. Finally, an appropriate amount of yttrium oxide powder reacts with the remaining silica powder at a high temperature. Yttrium pyrosilicate is generated, which can lower the nucleation barrier of the mullite phase, thereby promoting its formation. Furthermore, the tetragonal zirconium dioxide dispersed at the grain boundaries separates the remaining alumina powder from the high-alumina glass phase formed by the decomposition of silica at high temperatures and after cooling, forming a discontinuous high-alumina glass phase. The remaining yttrium oxide powder maintains the stability of the tetragonal zirconium dioxide at temperatures greater than or equal to 1170°C, forming a composite grain boundary phase of "mullite phase - discontinuous high-alumina glass phase - tetragonal zirconium dioxide dispersed particles". During the smelting of metal using the refractory crucible in this embodiment, it helps to avoid the formation of continuous glass in the refractory crucible at high temperatures. This process improves the high-temperature strength and thermal shock resistance of refractory crucibles. Similarly, when zirconium silicate powder does not decompose to form silicon dioxide and monoclinic zirconium dioxide, zirconium silicate powder forms dispersed zirconium silicate particles at grain boundaries between 1170-1540℃. These dispersed zirconium silicate particles at grain boundaries separate the remaining alumina powder from the high-alumina glass phase formed by the decomposed silicon dioxide at high temperatures and the high-alumina glass phase formed after cooling, forming a discontinuous high-alumina glass phase. This creates a composite grain boundary phase of "mullite phase - discontinuous high-alumina glass phase - dispersed zirconium silicate particles," which also helps to prevent the formation of a continuous glass phase in the refractory crucible at high temperatures, thus improving the high-temperature strength and thermal shock resistance of the refractory crucible.Furthermore, the refractory crucible in this embodiment experiences conditions similar to sintering conditions during metal smelting, essentially undergoing a cyclical sintering process. Therefore, the refractory crucible in this embodiment also possesses the aforementioned advantages during use.

[0007] In addition, based on the above technical solution, the present invention can be further improved as follows, and can also have the following additional technical features.

[0008] According to one embodiment of this application, the body, based on the total weight parts of the raw materials, further includes the following components in parts by weight: The dispersant comprises 0.5-3 parts, the initiator comprises 1-3 parts, and the organic catalyst comprises 0.5-2 parts. The dispersant, the initiator, and the organic catalyst are decomposed and volatilized after high-temperature sintering.

[0009] The raw materials in this embodiment include an appropriate amount of dispersant. During the preparation of the refractory slurry for molding, the dispersant can depolymerize and disperse the refractory slurry, which helps eliminate localized uneven concentrations and improves its homogeneity. The dispersant also helps improve the static stability of the refractory slurry, preventing the formation of a thin upper layer and a precipitated lower layer. Furthermore, the dispersant effectively reduces the overall viscosity of the refractory slurry, improving its fluidity. Additionally, the raw materials in this embodiment include an appropriate amount of initiator. During the preparation of the refractory slurry for molding, the initiator can initiate a chain polymerization reaction, allowing the refractory slurry to... The refractory slurry gradually transforms into a solid gel. Furthermore, the added initiator is suitable, which helps to determine the initiation speed, reaction rate, and degree of curing of the polymerization reaction. A stable initiation process also allows the slurry system to cross-link and cure simultaneously, reducing problems such as curing shrinkage, porosity, and cracking, and improving the density, mechanical strength, and structural stability of the cured product. In addition, the raw materials in this embodiment include an appropriate amount of organic catalyst. During the preparation of the refractory slurry used for molding the body, the curing speed and cross-linking density of the refractory slurry can be precisely controlled by the organic catalyst, avoiding problems such as gel agglomeration due to excessively fast reaction and excessively slow reaction leading to excessively long production cycles.

[0010] According to one embodiment of this application, the dispersant is any one or more of ammonium polyacrylate or polyacrylic acid, the initiator is ammonium persulfate, and the organic catalyst is tetramethylethylenediamine.

[0011] In this embodiment, the dispersant is any one or more of ammonium polyacrylate or polyacrylic acid. Both ammonium polyacrylate and polyacrylic acid contain abundant carboxylic acid groups, which can be firmly adsorbed on the surface of the powder particles in this embodiment. Moreover, ammonium polyacrylate or polyacrylic acid can significantly reduce the viscosity of the system under the premise of high solid content of slurry, which is beneficial to improving the fluidity and leveling of slurry. In addition, ammonium polyacrylate or polyacrylic acid can be completely decomposed and volatilized in the subsequent high-temperature sintering process, leaving no metal ion residue, which is beneficial to improving the quality of the formed refractory crucible. Furthermore, the initiator is ammonium persulfate, which is convenient for improving the initiation efficiency and initiation stability, and can be completely decomposed and volatilized in the subsequent high-temperature sintering process. Furthermore, the organic catalyst is tetramethylethylenediamine, which is beneficial to ensure precise control of the curing speed and crosslinking density of refractory slurry, and is also beneficial to volatilization and decomposition and removal in the debinding process of refractory crucible preparation, without affecting the densification of refractory crucible sintering, which is beneficial to improving the quality of refractory crucible obtained by sintering.

[0012] According to one embodiment of this application, the particle size of the corundum aggregate is 100-1000 μm, the particle size of the alumina powder is 5-30 μm, the particle size of the silica powder is 5-30 μm, the particle size of the yttrium oxide powder is 2-10 μm, and the particle size of the zirconium silicate powder is 5-20 μm.

[0013] In this embodiment, the particle size of the corundum aggregate is 100-1000μm, which is beneficial for the corundum aggregate to provide reliable support when used as a skeleton. Furthermore, the particle sizes of the alumina powder, silica powder, yttrium oxide powder, and zirconium silicate powder are suitable, and the particle size of all powders is one order of magnitude smaller than that of the corundum aggregate. After sintering, the dry crucible green body containing the corundum aggregate and all the powders achieves a structural combination of large aggregate bearing, fine powder filling, and ultrafine powder modification, without affecting the supporting role of the aggregate skeleton, while maximizing the filling of voids.

[0014] According to one embodiment of this application, the method for preparing the liquid carrier includes: The organic monomer and the crosslinking agent are dissolved in deionized water and stirred evenly to prepare a mixture. The mass ratio of the organic monomer to the crosslinking agent is (10-30):1. The total mass fraction of the organic monomer and the crosslinking agent in the mixture is 10%-25%, and the remainder is deionized water. A binder is added to the prepared mixture and stirred until homogeneous to prepare the liquid carrier; wherein the mass of the added binder is 3%-10% of the total mass of the weighed alumina powder, silica powder, yttrium oxide powder and zirconium silicate powder.

[0015] In this embodiment, the liquid carrier contains appropriate amounts of organic monomers, crosslinkers, and binders. This is beneficial because the organic monomers are responsible for reducing viscosity and dispersing, preventing powder agglomeration and slurry stratification; the crosslinkers stabilize the molecular structure of the system; and the binders help ensure that the particles remain suspended and do not settle. In addition, the appropriate combination of organic monomers, crosslinkers, and binders is beneficial because the mixed slurry with high solid content obtained by mixing the liquid carrier and powder raw materials has the advantages of good fluidity and high uniformity.

[0016] According to one embodiment of this application, the organic monomer is any one or more of acrylamide and methacrylamide, the crosslinking agent is methylenebisacrylamide, and the binder is any one or more of polyvinyl alcohol, silica sol, or aluminum sol.

[0017] In this embodiment, the organic monomer is any one or more of acrylamide or methacrylamide. Acrylamide and methacrylamide have the advantages of high reactivity, strong hydrophilicity, crosslinkability, and good thermal stability. Furthermore, the crosslinking agent in this embodiment is methylenebisacrylamide. Methylenebisacrylamide has amide polar groups, good water solubility, and uniform dispersion in the aqueous phase. Furthermore, the binder in this embodiment is any one or more of polyvinyl alcohol, silica sol, or aluminum sol. When a high solid content mixed slurry is obtained by mixing a liquid carrier containing polyvinyl alcohol, silica sol, or aluminum sol with powder raw materials, it is beneficial to optimize the flowability of the mixed slurry. Moreover, using the obtained mixed slurry to form crucible green bodies is beneficial to improving the forming strength of the crucible green bodies. In addition, it is beneficial to reduce sintering defects in the crucible green bodies.

[0018] According to one embodiment of this application, the temperature range of the high temperature is 1350-1420°C.

[0019] In this embodiment, the high temperature range is 1350-1420℃. Yttrium trioxide powder reacts with the remaining silica powder at 1350-1420℃ to generate yttrium pyrosilicate, obtaining a high-purity, stable, high-temperature phase with excellent thermal, mechanical, and chemical stability. This also helps to avoid the conversion of yttrium pyrosilicate to yttrium monosilicate, avoid impurities, and facilitate the obtaining of a stable single yttrium pyrosilicate phase.

[0020] According to another aspect of this application, a method for preparing a refractory crucible capable of withstanding repeated high-temperature thermal shock is provided, the method comprising: Weigh the following raw materials according to the following parts by weight: 8-12 parts liquid carrier, 70-85 parts corundum aggregate, 5-12 parts aluminum oxide powder, 3-10 parts silica powder, 0.3-1 parts yttrium oxide powder, and 3-8 parts zirconium silicate powder; The weighed corundum aggregate, aluminum oxide powder, silicon dioxide powder, yttrium oxide powder and zirconium silicate powder are mixed to obtain a mixed powder; The weighed liquid carrier is added to the obtained mixed powder and ball-milled until uniformly mixed to obtain a mixed slurry with high solid content; The obtained mixed slurry is injected into the injection molding cavity of the crucible forming mold for injection molding, and then demolded to obtain a crucible green blank; The obtained crucible green blank is then dried. The dried crucible green is sintered and cooled to obtain the refractory crucible capable of withstanding multiple high-temperature thermal shocks. During high-temperature sintering, 4-10 parts of alumina powder and 2-9 parts of silica powder undergo a solid-phase diffusion reaction to form a mullite phase in situ. The remaining unreacted alumina powder and the remaining unreacted silica powder melt at high temperature to form an aluminosilicate liquid phase, which then cools to form a high-alumina glass phase. 0.2-0.9 parts of yttrium oxide powder react with the remaining silica powder at a lower temperature to form yttrium pyrosilicate. 3-8 parts of zirconium silicate powder decompose at temperatures above 1540°C to form silica and monoclinic zirconium dioxide, and the decomposed monoclinic zirconium dioxide undergoes a phase transformation at temperatures above 1170°C to form… Tetragonal zirconia is dispersed at grain boundaries, causing the remaining alumina powder to separate from the high-alumina glass phase formed by the decomposition of silica at high temperature and the high-alumina glass phase formed after cooling, forming a discontinuous high-alumina glass phase. The remaining yttrium oxide powder maintains the stability of the tetragonal zirconia at a temperature greater than or equal to 1170°C, forming a composite grain boundary phase of "mullite phase-discontinuous high-alumina glass phase-tetragonal zirconia dispersed particles". The corundum aggregate forms a continuous three-dimensional network structure and serves as the framework of the formed composite grain boundary phase of "mullite phase-discontinuous high-alumina glass phase-tetragonal zirconia dispersed particles". The generated yttrium pyrosilicate can reduce the nucleation barrier of the mullite phase, and the liquid carrier evaporates and is removed. Alternatively, after high-temperature sintering, 4-10 parts of the alumina powder and 2-9 parts of the silica powder undergo a solid-phase diffusion reaction at high temperature to form a mullite phase in situ. The remaining unreacted alumina powder and the remaining unreacted silica powder melt at high temperature to form an aluminosilicate liquid phase, which then forms a high-alumina glass phase after cooling. 0.3-1 parts of the yttrium oxide powder react with the remaining silica powder at a temperature below a certain high temperature to form yttrium pyrosilicate. 3-8 parts of the zirconium silicate powder form dispersed zirconium silicate particles at the grain boundaries between 1170-1540℃. The dispersed zirconium silicate particles at the grain boundaries cause the remaining alumina powder to separate from the high-alumina glass phase formed by the decomposition of silica at high temperature and the high-alumina glass phase formed after cooling, forming a discontinuous high-alumina glass phase, thus forming a "mullite phase-discontinuous high-alumina glass phase-zirconia silicate dispersed particles" composite grain boundary phase. The corundum aggregate forms a continuous three-dimensional network structure and serves as the framework for the formed "mullite phase-discontinuous high-alumina glass phase-zirconia silicate dispersed particles" composite grain boundary phase. The generated yttrium pyrosilicate can reduce the nucleation barrier of the mullite phase, and the liquid carrier evaporates and removes it.

[0021] In the preparation method of the refractory crucible capable of withstanding multiple high-temperature thermal shocks in this embodiment, the dried crucible green blank is sintered and cooled to obtain a refractory crucible capable of withstanding multiple high-temperature thermal shocks. Further, by adding appropriate amounts of alumina powder and silica powder, during the sintering of the crucible green blank to form the refractory crucible, the alumina powder and silica powder react in situ at high temperature to generate a mullite phase. The remaining unreacted alumina powder and the remaining unreacted silica powder melt at high temperature to form an aluminosilicate liquid phase. After cooling, the aluminosilicate liquid phase forms a high-alumina glass phase, generating a mullite phase that transforms the continuous glass phase into a composite grain boundary phase of "mullite whiskers-discontinuous high-alumina glass phase." The mullite phase is characterized by whiskers. The morphology of the yttrium oxide powder plays a role in grain boundary pinning, significantly improving the high-temperature strength of the bulk material and thus the high-temperature strength of the refractory crucible. Furthermore, the alumina and silica powders that did not undergo in-situ mullite phase formation during high-temperature reaction form a residual high-alumina glassy phase. This residual high-alumina glassy phase exhibits viscous flow characteristics at high temperatures, which can relax thermal stress and improve the thermal shock resistance of the bulk material, thereby improving the thermal shock resistance of the refractory crucible. Further, an appropriate amount of yttrium oxide powder reacts with the remaining silica powder at a high temperature to form yttrium pyrosilicate. The generated yttrium pyrosilicate can lower the nucleation barrier of the mullite phase, thus promoting mullite phase formation. Finally, the tetragonal zirconium dioxide dispersed at the grain boundaries allows the remaining alumina... The alumina powder and the silica formed by its decomposition create a high-alumina glass phase at high temperatures and a high-alumina glass phase formed after cooling, forming a discontinuous high-alumina glass phase. The remaining yttrium oxide powder maintains the stability of tetragonal zirconium dioxide at temperatures greater than or equal to 1170°C, forming a composite grain boundary phase of "mullite phase - discontinuous high-alumina glass phase - tetragonal zirconium dioxide dispersed particles". When using the refractory crucible in this embodiment for metal smelting, it helps to avoid the formation of a continuous glass phase in the refractory crucible at high temperatures, thereby improving the high-temperature strength and thermal shock resistance of the refractory crucible. Similarly, when the zirconium silicate powder does not decompose to form silica and monoclinic zirconium dioxide, the zirconium silicate powder forms at grain boundaries between 1170-1540°C. The dispersed zirconium silicate particles, especially those at the grain boundaries, separate the remaining alumina powder from the high-alumina glass phase formed by the decomposition of silica at high temperatures and the high-alumina glass phase formed after cooling, creating a discontinuous high-alumina glass phase. This forms a composite grain boundary phase of "mullite phase - discontinuous high-alumina glass phase - zirconium silicate particles," which also helps to prevent the formation of a continuous glass phase in the refractory crucible at high temperatures, thereby improving the high-temperature strength and thermal shock resistance of the refractory crucible. Furthermore, the refractory crucible in this embodiment experiences conditions similar to sintering conditions during the smelting of metals, similar to cyclically undergoing sintering conditions. Therefore, the refractory crucible in this embodiment also possesses the aforementioned advantages during use.

[0022] According to one embodiment of this application, the preparation method further includes: Weigh out 0.5-3 parts of dispersant, 1-3 parts of initiator, and 0.5-2 parts of organic catalyst; After adding the weighed liquid carrier to the obtained mixed powder, and before ball milling until homogeneous, the preparation method further includes: Add the weighed dispersant to the obtained mixed powder; After obtaining the mixed slurry with high solid content, and before injecting the obtained mixed slurry into the injection molding cavity of the crucible molding die for injection molding, the preparation method further includes: The initiator and the organic catalyst are added to the obtained mixed slurry, and the mixed slurry after adding the initiator and the organic catalyst is mixed evenly. Then, vacuum degassing is performed to remove air bubbles from the mixed slurry. After drying the obtained crucible green blank, and before sintering and cooling the dried crucible green blank, the preparation method further includes: The dried crucible blank is placed in a debinding furnace for debinding to remove organic matter.

[0023] In this embodiment, 0.5-3 parts of dispersant, 1-3 parts of initiator, and 0.5-2 parts of organic catalyst are weighed out. Adding the weighed dispersant to the obtained mixed powder allows for depolymerization and dispersion of the refractory slurry, which helps eliminate localized uneven concentrations and improves the homogeneity of the refractory slurry. The dispersant also helps improve the static stability of the refractory slurry, preventing the formation of a thin upper layer and a precipitated lower layer. Furthermore, the dispersant effectively reduces the overall viscosity of the refractory slurry, improving its fluidity. Further, adding the weighed initiator and organic catalyst to the obtained mixed slurry allows the initiator to initiate a chain polymerization reaction, gradually transforming the refractory slurry into a solid gel. Additionally, the appropriate amount of initiator helps determine the initiation of the polymerization reaction. The process controls the speed, reaction rate, and degree of curing; a stable initiation process also allows the slurry system to cross-link and cure simultaneously, reducing problems such as curing shrinkage, porosity, and cracking, and improving the density, mechanical strength, and structural stability of the cured product. In addition, the curing speed and cross-linking density of the refractory slurry can be precisely controlled by organic catalysts to avoid problems such as gel agglomeration due to excessively fast reaction and excessively long production cycles due to excessively slow reaction. Furthermore, the dried crucible green body is placed in a debinding furnace for debinding treatment to remove organic matter. During subsequent high-temperature sintering, this helps to prevent the organic matter inside the crucible green body from vaporizing and decomposing when heated, generating a large amount of gas trapped inside the crucible green body, which can easily cause defects such as cracking, bubbling, delamination, and pore voids in the crucible green body. It can also improve the density and strength of the sintered refractory crucible.

[0024] According to one embodiment of this application, the dispersant is any one or more of ammonium polyacrylate or polyacrylic acid, the initiator is ammonium persulfate, and the organic catalyst is tetramethylethylenediamine.

[0025] In this embodiment, the dispersant is any one or more of ammonium polyacrylate or polyacrylic acid. Both ammonium polyacrylate and polyacrylic acid contain abundant carboxylic acid groups, which can be firmly adsorbed on the surface of the powder particles in this embodiment. Moreover, ammonium polyacrylate or polyacrylic acid can significantly reduce the viscosity of the system under the premise of high solid content of slurry, which is beneficial to improving the fluidity and leveling of slurry. In addition, ammonium polyacrylate or polyacrylic acid can be completely decomposed and volatilized in the subsequent high-temperature sintering process, leaving no metal ion residue, which is beneficial to improving the quality of the formed refractory crucible. Furthermore, the initiator is ammonium persulfate, which is convenient for improving the initiation efficiency and initiation stability, and can be completely decomposed and volatilized in the subsequent high-temperature sintering process. Furthermore, the organic catalyst is tetramethylethylenediamine, which is beneficial to ensure precise control of the curing speed and crosslinking density of refractory slurry, and is also beneficial to volatilization and decomposition and removal in the debinding process of refractory crucible preparation, without affecting the densification of refractory crucible sintering, which is beneficial to improving the quality of refractory crucible obtained by sintering.

[0026] According to one embodiment of this application, the method for preparing the liquid carrier includes: The organic monomer and the crosslinking agent are dissolved in deionized water and stirred evenly to prepare a mixture. The mass ratio of the organic monomer to the crosslinking agent is (10-30):1. The total mass fraction of the organic monomer and the crosslinking agent in the mixture is 10%-25%, and the remainder is deionized water. A binder is added to the prepared mixture and stirred until homogeneous to prepare the liquid carrier; wherein the mass of the added binder is 3%-10% of the total mass of the weighed alumina powder, silica powder, yttrium oxide powder, and zirconium silicate powder; The process of injecting the obtained mixed slurry into the injection molding cavity of the crucible molding mold for injection molding and then demolding is specifically as follows: The obtained mixed slurry is injected into the injection molding cavity of the crucible molding mold, where the organic monomers are polymerized and gelled in situ to form a three-dimensional network structure, causing the mixed slurry filling the injection molding cavity to solidify, and then demolding is performed.

[0027] In this embodiment, the liquid carrier contains appropriate amounts of organic monomers, crosslinkers, and binders. The organic monomers are responsible for reducing viscosity and dispersing, preventing powder agglomeration and slurry stratification; the crosslinkers stabilize the molecular structure of the system; and the binders ensure particle suspension without sedimentation. Furthermore, the appropriate combination of organic monomers, crosslinkers, and binders ensures that the high-solid-content mixed slurry obtained by mixing the liquid carrier with the powder raw materials has advantages such as good fluidity and high uniformity. Further, the in-situ polymerization and gelation of the organic monomers forms a three-dimensional network structure, and the crosslinked network strengthens and reinforces the crucible green body formed by the curing of the mixed slurry, improving its strength, elasticity, and resistance to deformation, thereby enhancing the quality of the crucible green body formed by the curing of the mixed slurry.

[0028] According to one embodiment of this application, the organic monomer is any one or more of acrylamide and methacrylamide, the crosslinking agent is methylenebisacrylamide, and the binder is any one or more of polyvinyl alcohol, silica sol, or aluminum sol.

[0029] In this embodiment, the organic monomer is any one or more of acrylamide or methacrylamide. Acrylamide and methacrylamide have the advantages of high reactivity, strong hydrophilicity, crosslinkability, and good thermal stability. Furthermore, the crosslinking agent in this embodiment is methylenebisacrylamide. Methylenebisacrylamide has amide polar groups, good water solubility, and uniform dispersion in the aqueous phase. Furthermore, the binder in this embodiment is any one or more of polyvinyl alcohol, silica sol, or aluminum sol. When a high solid content mixed slurry is obtained by mixing a liquid carrier containing polyvinyl alcohol, silica sol, or aluminum sol with powder raw materials, it is beneficial to optimize the flowability of the mixed slurry. Moreover, using the obtained mixed slurry to form crucible green bodies is beneficial to improving the forming strength of the crucible green bodies. In addition, it is beneficial to reduce sintering defects in the crucible green bodies.

[0030] According to one embodiment of this application, the vacuum degassing is carried out in a vacuum environment with a vacuum degree of -0.08 to -0.095 MPa, and the vacuum degassing time is 10-30 min; The temperature range for in-situ polymerization and gelation of the organic monomer is 40-60℃, and the duration of in-situ polymerization and gelation of the organic monomer is 30-120 min. The drying process of the obtained crucible green blank includes: In the first drying stage, the obtained crucible green blank is placed in a constant temperature and humidity space with a relative humidity of 50-80% and a temperature of 30-50℃ for drying for 12-24 hours; In the second drying stage, the obtained crucible green blank is placed in a constant temperature and humidity space with a relative humidity of 10-30% and a temperature of 30-50℃ for drying for 24-48 hours; The conditions for placing the dried crucible blank in a debinding furnace for debinding treatment are as follows: Heating is carried out at a rate of 1-5℃ / min to a temperature of 400-600℃, and the holding time is 2-4h. The debinding atmosphere is air or argon. The sintering and cooling of the dried crucible green blank includes: The dried crucible blank is placed in a sintering furnace and sintered for 2-5 hours in an air atmosphere at a sintering temperature of 1360-1450°C at a heating rate of 2-10°C / min. After sintering, the crucible blank is cooled in the furnace.

[0031] In this embodiment, vacuum degassing is performed in a vacuum environment with a vacuum degree of -0.08 to -0.095 MPa for 10-30 minutes, which is beneficial for thoroughly removing air bubbles from the mixed slurry. Furthermore, the temperature range for in-situ polymerization and gelation of the organic monomers is 40-60℃, and the gelation time is 30-120 minutes. This helps avoid high-temperature damage to the matrix and powder properties, preventing thermal deformation and grain coarsening. The suitable gelation time also promotes uniform molding. This facilitates the formation of a dense and defect-free internal structure in the solidified crucible green blank. Furthermore, in this embodiment, the crucible green blank is dried through two drying stages. In the first drying stage, the crucible green blank is placed in a constant temperature and humidity environment with a relative humidity of 50-80% and a temperature of 30-50℃ for 12-24 hours. The relatively high humidity and gentle environment allow the surface moisture of the crucible green blank to evaporate slowly and evenly, avoiding rapid evaporation and crusting under high temperature and low humidity conditions. The first drying stage involves placing the crucible green blank in a space with a relative humidity of... Drying in a constant temperature and humidity environment of 30-50℃ for 24-48 hours at 10-30% humidity reduces dehumidification and prolongs the drying time, which helps to break down the resistance to moisture diffusion inside the crucible green body, allowing deep adsorbed water and pore-bound water to gradually migrate outward and evaporate completely. Furthermore, the crucible green body is debinded by heating at a rate of 1-5℃ / min to 400-600℃ and holding for 2-4 hours in an air or argon atmosphere, which helps to remove organic matter from the interior of the crucible green body. The process is clean, which helps prevent the crucible green from cracking and ensures moderate strength, while also providing conditions for high-quality sintering of the crucible green. Furthermore, the dried crucible green is placed in a sintering furnace and sintered for 2-5 hours in an air atmosphere at a heating rate of 2-10℃ / min to a temperature of 1360-1450℃. After that, it is cooled with the furnace, which helps to promote the tight bonding of the particles contained in the sintered refractory crucible and improves the density, mechanical strength and structural stability of the sintered refractory crucible. Attached Figure Description

[0032] To more clearly illustrate the technical solutions in this invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0033] Figure 1 This is a flowchart illustrating the preparation of a refractory crucible capable of withstanding multiple high-temperature thermal shocks in Example 1 of this application; Figure 2This is a scanning electron microscope (SEM) image of the fracture microstructure of the refractory crucible sample containing zirconium dioxide dispersed particles obtained in Example 1 of this application. Figure 3 This is a scanning electron microscope (SEM) image of the fracture microstructure of the refractory crucible sample containing mullite whiskers obtained in Example 1 of this application. Figure 4 XRD patterns of the refractory crucible sample prepared in Example 1 of this application before and after thermal shock cycling; Figure 5 SEM images of the refractory crucible sample prepared in Example 1 of this application after 0, 3, 5 and 10 thermal shocks; Figure 6 This is a comparison diagram of the high-temperature flexural strength at 1560 °C of the refractory crucible samples prepared in Examples 1 to 6 of this application; Figure 7 The graph shows the change in residual strength of the refractory crucible samples prepared in Examples 1 to 6 of this application after being subjected to a thermal shock cycle at 1500°C. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0035] To better understand the above-mentioned objectives, features, and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other.

[0036] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0037] It should be noted that the terms "comprising" and "having" and any variations thereof in this invention are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or device.

[0038] According to one aspect of this application, a refractory crucible capable of withstanding repeated high-temperature thermal shock is provided, comprising: The main body has a receiving cavity with one open end. The main body, based on the total weight of the raw materials, comprises the following components in parts by weight: The composition includes 8-12 parts liquid carrier, 70-85 parts corundum aggregate, 5-12 parts alumina powder, 3-10 parts silica powder, 0.3-1 parts yttrium oxide powder, and 3-8 parts zirconium silicate powder. After high-temperature sintering, 4-10 parts of alumina powder and 2-9 parts of silica powder undergo a solid-phase diffusion reaction to form a mullite phase in situ. The remaining unreacted alumina powder and some unreacted silica powder melt at high temperature to form an aluminosilicate liquid phase, which then cools to form a high-alumina glass phase. 0.2-0.9 parts of yttrium oxide powder react with the remaining silica powder at a lower temperature to form yttrium pyrosilicate. 3-8 parts of zirconium silicate powder decompose at temperatures above 1540℃ to form silica and monoclinic zirconium dioxide. The decomposed monoclinic zirconium dioxide... Zirconia undergoes a phase transformation above 1170℃ to form tetragonal zirconia dispersed at grain boundaries. This dispersed tetragonal zirconia causes the remaining alumina powder to separate from the high-alumina glass phase formed by the decomposition of silica at high temperatures and the high-alumina glass phase formed after cooling, forming a discontinuous high-alumina glass phase. The remaining yttrium oxide powder maintains the stability of tetragonal zirconia at temperatures greater than or equal to 1170℃, forming a composite grain boundary phase of "mullite phase - discontinuous high-alumina glass phase - tetragonal zirconia dispersed particles". The corundum aggregate forms a continuous three-dimensional network structure and serves as the framework for the formed composite grain boundary phase of "mullite phase - discontinuous high-alumina glass phase - tetragonal zirconia dispersed particles". The generated yttrium pyrosilicate can reduce the nucleation barrier of the mullite phase and is volatilized and removed by the liquid carrier. Alternatively, after high-temperature sintering, 4-10 parts of alumina powder and 2-9 parts of silica powder undergo a solid-phase diffusion reaction at high temperature to form a mullite phase in situ. The remaining unreacted alumina powder and the remaining unreacted silica powder melt at high temperature to form an aluminosilicate liquid phase. After cooling, the aluminosilicate liquid phase forms a high-alumina glass phase. 0.3-1 parts of yttrium oxide powder react with the remaining silica powder at a lower temperature to form yttrium pyrosilicate. 3-8 parts of zirconium silicate powder form dispersed zirconium silicate particles at the grain boundaries between 1170-1540℃. The dispersed zirconium silicate particles at the grain boundaries cause the remaining alumina powder to separate from the high-alumina glass phase formed by the decomposition of silica at high temperature and the high-alumina glass phase formed after cooling, forming a discontinuous high-alumina glass phase, thus forming a composite grain boundary phase of "mullite phase-discontinuous high-alumina glass phase-zirconia silicate particles". The corundum aggregate forms a continuous three-dimensional network structure and serves as the framework for the formed composite grain boundary phase of "mullite phase-discontinuous high-alumina glass phase-zirconia silicate particles". Among them, the generated yttrium pyrosilicate can reduce the nucleation barrier of the mullite phase and the liquid carrier volatilizes and is removed.

[0039] In this embodiment, the raw materials of the main body include appropriate amounts of liquid carrier, corundum aggregate, alumina powder, silica powder, yttrium oxide powder, and zirconium silicate powder. This facilitates the mixing of each powder with the liquid carrier to obtain a mixed slurry, which is then used to form a crucible green body, which is subsequently sintered to form a refractory crucible. Furthermore, by adding appropriate amounts of alumina powder and silica powder, during the sintering of the crucible green body to form a refractory crucible, the alumina powder and silica powder react in situ at high temperature to generate a mullite phase. The remaining unreacted alumina powder and the remaining unreacted silica powder melt at high temperature to form an aluminosilicate liquid phase. After the silicate liquid phase cools, a high-alumina glass phase forms, generating a mullite phase. This transforms the continuous glass phase into a composite grain boundary phase of "mullite whiskers-discontinuous high-alumina glass phase." The mullite phase, with its whisker morphology, acts as grain boundary pinning, significantly improving the high-temperature strength of the bulk material, thereby enhancing the high-temperature strength of the refractory crucible. Furthermore, the alumina powder and silica powder that did not undergo in-situ mullite phase formation during the high-temperature reaction form a residual high-alumina glass phase. This residual high-alumina glass phase exhibits viscous flow characteristics at high temperatures, which can relax thermal stress and improve the thermal shock resistance of the bulk material, thus enhancing the thermal shock resistance of the refractory crucible. Additionally, a suitable amount of yttrium oxide powder reacts with the remaining silica powder at a high temperature to generate… Yttrium pyrosilicate is formed, which lowers the nucleation barrier of the mullite phase, thereby promoting its formation. Furthermore, the tetragonal zirconium dioxide dispersed at the grain boundaries separates the remaining alumina powder from the high-alumina glass phase formed by the decomposition of silica at high temperatures and after cooling, forming a discontinuous high-alumina glass phase. The remaining yttrium oxide powder maintains the stability of the tetragonal zirconium dioxide at temperatures greater than or equal to 1170°C, forming a composite grain boundary phase of "mullite phase - discontinuous high-alumina glass phase - tetragonal zirconium dioxide dispersed particles." Using the refractory crucible in this embodiment for metal smelting helps avoid the formation of a continuous glass phase in the refractory crucible at high temperatures. This improves the high-temperature strength and thermal shock resistance of refractory crucibles. Similarly, when zirconium silicate powder does not decompose to form silicon dioxide and monoclinic zirconium dioxide, zirconium silicate powder forms dispersed zirconium silicate particles at the grain boundaries between 1170-1540℃. These dispersed zirconium silicate particles at the grain boundaries separate the remaining alumina powder from the high-alumina glass phase formed by the decomposed silicon dioxide at high temperatures and the high-alumina glass phase formed after cooling, forming a discontinuous high-alumina glass phase. This creates a composite grain boundary phase of "mullite phase - discontinuous high-alumina glass phase - dispersed zirconium silicate particles," which also helps to avoid the formation of a continuous glass phase in the refractory crucible at high temperatures, thus improving the high-temperature strength and thermal shock resistance of the refractory crucible.Furthermore, the refractory crucible in this embodiment experiences conditions similar to sintering conditions during metal smelting, essentially undergoing a cyclical sintering process. Therefore, the refractory crucible in this embodiment also possesses the aforementioned advantages during use.

[0040] It should be noted that, based on the following components by weight: "8-12 parts liquid carrier, 70-85 parts corundum aggregate, 5-12 parts alumina powder, 3-10 parts silica powder, 0.3-1 parts yttrium oxide powder, and 3-8 parts zirconium silicate powder", appropriate amounts of each raw material can be weighed and mixed to obtain various mixed slurries with different proportions. Using the obtained mixed slurries with different proportions to prepare refractory crucibles, different refractory crucibles can be obtained.

[0041] In one embodiment of this application, the main body, based on the total weight parts of the raw materials, further includes the following components in parts by weight: The dispersant consists of 0.5-3 parts, the initiator consists of 1-3 parts, and the organic catalyst consists of 0.5-2 parts. During high-temperature sintering, the dispersant, initiator, and organic catalyst decompose and volatilize respectively.

[0042] In this embodiment, the raw materials include an appropriate amount of dispersant. During the preparation of the refractory slurry for molding the body, the dispersant can depolymerize and disperse the refractory slurry, which helps to eliminate the problem of uneven local concentration in the refractory slurry and improve the homogeneity of the refractory slurry. The dispersant also helps to improve the static stability of the refractory slurry and avoid the phenomenon of thin upper layer and sedimentation and agglomeration in lower layer. In addition, the dispersant can effectively reduce the overall viscosity of the refractory slurry and improve its fluidity. Furthermore, the raw materials in this embodiment include an appropriate amount of initiator. During the preparation of the refractory slurry for molding the body, the initiator can initiate the chain polymerization reaction. This process allows the refractory slurry to gradually transform into a solid gel. Furthermore, the added initiator is suitable, which helps to determine the initiation speed, reaction rate, and degree of curing of the polymerization reaction. A stable initiation process also allows the slurry system to cross-link and cure simultaneously, reducing problems such as curing shrinkage, porosity, and cracking, and improving the density, mechanical strength, and structural stability of the cured product. In addition, the raw materials in this embodiment include an appropriate amount of organic catalyst. During the preparation of the refractory slurry used for molding, the curing speed and cross-linking density of the refractory slurry can be precisely controlled by the organic catalyst, avoiding problems such as gel agglomeration due to excessively fast reaction and excessively slow reaction leading to excessively long production cycles.

[0043] In one embodiment of this application, the dispersant is ammonium polyacrylate or any one or more of polyacrylic acid, the initiator is ammonium persulfate, and the organic catalyst is tetramethylethylenediamine.

[0044] In this embodiment, the dispersant is any one or more of ammonium polyacrylate or polyacrylic acid. Both ammonium polyacrylate and polyacrylic acid contain abundant carboxylic acid groups, which can be firmly adsorbed on the surface of the powder particles in this embodiment. Moreover, ammonium polyacrylate or polyacrylic acid can significantly reduce the viscosity of the system under the premise of high solid content of slurry, which is beneficial to improving the fluidity and leveling of slurry. In addition, ammonium polyacrylate or polyacrylic acid can be completely decomposed and volatilized in the subsequent high-temperature sintering process, leaving no metal ion residue, which is beneficial to improving the quality of the formed refractory crucible. Furthermore, the initiator is ammonium persulfate, which is convenient to improve the initiation efficiency and initiation stability, and can be completely decomposed and volatilized in the subsequent high-temperature sintering process. Furthermore, the organic catalyst is tetramethylethylenediamine, which is beneficial to ensure precise control of the curing speed and crosslinking density of refractory slurry, and is also beneficial to volatilization and decomposition and removal in the debinding process of refractory crucible preparation, without affecting the densification of refractory crucible sintering, which is beneficial to improving the quality of refractory crucible obtained by sintering.

[0045] In one embodiment of this application, the particle size of corundum aggregate is 100-1000 μm, the particle size of alumina powder is 5-30 μm, the particle size of silica powder is 5-30 μm, the particle size of yttrium oxide powder is 2-10 μm, and the particle size of zirconium silicate powder is 5-20 μm.

[0046] In this embodiment, the particle size of the corundum aggregate is 100-1000μm, which is beneficial for the corundum aggregate to provide reliable support when used as a skeleton. Furthermore, the particle sizes of the alumina powder, silica powder, yttrium oxide powder, and zirconium silicate powder are suitable, and the particle size of all powders is one order of magnitude smaller than that of the corundum aggregate. After sintering, the dry crucible green body containing the corundum aggregate and all the powders achieves a structural combination of large aggregate bearing, fine powder filling, and ultrafine powder modification, without affecting the supporting role of the aggregate skeleton, while maximizing the filling of voids.

[0047] It should be noted that the corundum aggregate can be any or more particle sizes ranging from 100 to 1000 μm, the alumina powder can be any or more particle sizes ranging from 5 to 30 μm, the silica powder can be any or more particle sizes ranging from 5 to 30 μm, the yttrium oxide powder can be any or more particle sizes ranging from 2 to 10 μm, and the zirconium silicate powder can be any or more particle sizes ranging from 5 to 20 μm.

[0048] In one embodiment of this application, the method for preparing the liquid carrier includes: Organic monomers and crosslinking agents are dissolved in deionized water and stirred evenly to prepare mixture one, wherein the mass ratio of organic monomers to crosslinking agents is (10-30):1, the total mass fraction of organic monomers and crosslinking agents in mixture one is 10%-25%, and the remainder is deionized water; Add a binder to the prepared mixture and stir until homogeneous to prepare a liquid carrier; wherein the mass of the added binder is 3%-10% of the total mass of the weighed alumina powder, silica powder, yttrium oxide powder and zirconium silicate powder.

[0049] In this embodiment, the liquid carrier contains appropriate amounts of organic monomers, crosslinking agents, and binders. This is beneficial because the organic monomers are responsible for reducing viscosity and dispersing, preventing powder agglomeration and slurry stratification; the crosslinking agents stabilize the molecular structure of the system; and the binders help ensure that the particles remain suspended and do not settle. In addition, the appropriate combination of organic monomers, crosslinking agents, and binders is beneficial because the mixed slurry with high solid content obtained by mixing the liquid carrier and powder raw materials has the advantages of good fluidity and high uniformity.

[0050] In one embodiment of this application, the organic monomer is any one or more of acrylamide and methacrylamide, the crosslinking agent is methylenebisacrylamide, and the binder is any one or more of polyvinyl alcohol, silica sol, or aluminum sol.

[0051] In this embodiment, the organic monomer is any one or more of acrylamide or methacrylamide. Acrylamide and methacrylamide have the advantages of high reactivity, strong hydrophilicity, crosslinkability, and good thermal stability. Furthermore, the crosslinking agent in this embodiment is methylenebisacrylamide. Methylenebisacrylamide has amide polar groups, good water solubility, and uniform dispersion in the aqueous phase. Furthermore, the binder in this embodiment is any one or more of polyvinyl alcohol, silica sol, or aluminum sol. When a high solid content mixed slurry is obtained by mixing a liquid carrier containing polyvinyl alcohol, silica sol, or aluminum sol with powder raw materials, it is beneficial to optimize the flowability of the mixed slurry. Moreover, using the obtained mixed slurry to form crucible green bodies is beneficial to improving the forming strength of the crucible green bodies. In addition, it is beneficial to reduce sintering defects in the crucible green bodies.

[0052] In one embodiment of this application, the temperature range of the high temperature is 1350-1420°C.

[0053] In this embodiment, the high temperature range is 1350-1420℃. Yttrium trioxide powder reacts with the remaining silica powder at 1350-1420℃ to generate yttrium pyrosilicate, obtaining a high-purity, stable, high-temperature phase with excellent thermal, mechanical, and chemical stability. This also helps to avoid the conversion of yttrium pyrosilicate to yttrium monosilicate, avoid impurities, and facilitate the obtaining of a stable single yttrium pyrosilicate phase.

[0054] Another aspect of this application provides a method for preparing a refractory crucible capable of withstanding repeated high-temperature thermal shocks, the method comprising the following steps: Step S102: Weigh the following raw materials according to their weight proportions: 8-12 parts liquid carrier, 70-85 parts corundum aggregate, 5-12 parts aluminum oxide powder, 3-10 parts silica powder, 0.3-1 parts yttrium oxide powder, and 3-8 parts zirconium silicate powder; Step S104: The weighed corundum aggregate, alumina powder, silica powder, yttrium oxide powder and zirconium silicate powder are mixed to obtain a mixed powder. Step S106: Add the weighed liquid carrier to the obtained mixed powder and ball mill it until it is uniformly mixed to obtain a mixed slurry with high solid content. Step S108: The obtained mixed slurry is injected into the injection molding cavity of the crucible molding mold for injection molding and then demolded to obtain the crucible green blank. Step S110: Dry the obtained crucible green blank; Step S112 involves sintering and cooling the dried crucible green to obtain a refractory crucible capable of withstanding multiple high-temperature thermal shocks. During high-temperature sintering, 4-10 parts of alumina powder and 2-9 parts of silica powder undergo a solid-state diffusion reaction to form a mullite phase in situ. The remaining unreacted alumina powder and some unreacted silica powder melt at high temperature to form an aluminosilicate liquid phase, which then cools to form a high-alumina glass phase. 0.2-0.9 parts of yttrium oxide powder react with the remaining silica powder at a lower temperature to form yttrium pyrosilicate. 3-8 parts of zirconium silicate powder decompose at temperatures above 1540℃ to form silica and monoclinic zirconium dioxide, with the resulting monoclinic zirconium dioxide undergoing a phase transition at temperatures above 1170℃. Tetragonal zirconia is dispersed at grain boundaries, which causes the remaining alumina powder to separate from the high-alumina glass phase formed by the decomposition of silica at high temperature and the high-alumina glass phase formed after cooling, forming a discontinuous high-alumina glass phase. The remaining yttrium oxide powder maintains the stability of tetragonal zirconia at a temperature greater than or equal to 1170℃, forming a composite grain boundary phase of "mullite phase-discontinuous high-alumina glass phase-tetragonal zirconia dispersed particles". The corundum aggregate forms a continuous three-dimensional network structure and serves as the framework of the formed composite grain boundary phase of "mullite phase-discontinuous high-alumina glass phase-tetragonal zirconia dispersed particles". Among them, the generated yttrium pyrosilicate can reduce the nucleation barrier of the mullite phase and the liquid carrier volatilizes and is removed.

[0055] In this embodiment, another sintering process for obtaining a refractory crucible capable of withstanding multiple high-temperature thermal shocks is as follows: After high-temperature sintering, 4-10 parts of alumina powder and 2-9 parts of silica powder undergo a solid-phase diffusion reaction at high temperature to generate a mullite phase in situ. The remaining unreacted alumina powder and the remaining unreacted silica powder melt at high temperature to form an aluminosilicate liquid phase. After cooling, the aluminosilicate liquid phase forms a high-alumina glass phase. 0.3-1 parts of yttrium oxide powder react with the remaining silica powder at a temperature below the high temperature to generate yttrium pyrosilicate. 3-8 parts of zirconium silicate powder form a... The dispersed zirconium silicate particles at the grain boundaries cause the remaining alumina powder to separate from the high-alumina glass phase formed by the decomposition of silica at high temperature and the high-alumina glass phase formed after cooling, forming a discontinuous high-alumina glass phase. This results in a composite grain boundary phase of "mullite phase-discontinuous high-alumina glass phase-zirconia silicate particles". The corundum aggregate forms a continuous three-dimensional network structure and serves as the framework for the composite grain boundary phase of "mullite phase-discontinuous high-alumina glass phase-zirconia silicate particles". The generated yttrium pyrosilicate can reduce the nucleation barrier of the mullite phase and is volatilized and removed by the liquid carrier.

[0056] In this embodiment, the method for preparing a refractory crucible capable of withstanding repeated high-temperature thermal shock involves sintering and cooling a dried crucible green blank to obtain a refractory crucible capable of withstanding repeated high-temperature thermal shock. Further, by adding appropriate amounts of alumina powder and silica powder, during the sintering process of the crucible green blank to form a refractory crucible, the alumina powder and silica powder react in situ at high temperature to generate a mullite phase. The remaining unreacted alumina powder and the remaining unreacted silica powder melt at high temperature to form an aluminosilicate liquid phase. After cooling, the aluminosilicate liquid phase forms a high-alumina glass phase, generating a mullite phase that transforms the continuous glass phase into a composite grain boundary phase of "mullite whiskers-discontinuous high-alumina glass phase." The yttrium phase, with its whisker morphology, acts as grain boundary pinning, significantly improving the high-temperature strength of the bulk material and thus the high-temperature strength of the refractory crucible. Furthermore, the alumina and silica powders that did not undergo in-situ mullite formation during high-temperature reaction form a residual high-alumina glassy phase. This residual high-alumina glassy phase exhibits viscous flow characteristics at high temperatures, which can relax thermal stress and improve the thermal shock resistance of the bulk material, thereby improving the thermal shock resistance of the refractory crucible. Further, an appropriate amount of yttrium oxide powder reacts with the remaining silica powder at high temperatures to form yttrium pyrosilicate. The generated yttrium pyrosilicate can lower the nucleation barrier of the mullite phase, thus promoting mullite phase formation. Finally, the tetragonal zirconium dioxide dispersed at the grain boundaries makes the remaining... The alumina powder and the silica formed by its decomposition create a high-alumina glass phase at high temperatures and a high-alumina glass phase formed after cooling, forming a discontinuous high-alumina glass phase. The remaining yttrium oxide powder maintains the stability of tetragonal zirconium dioxide at temperatures greater than or equal to 1170°C, forming a composite grain boundary phase of "mullite phase - discontinuous high-alumina glass phase - tetragonal zirconium dioxide dispersed particles". When using the refractory crucible in this embodiment for metal smelting, it helps to avoid the formation of a continuous glass phase in the refractory crucible at high temperatures, thereby improving the high-temperature strength and thermal shock resistance of the refractory crucible. Similarly, when the zirconium silicate powder does not decompose to form silica and monoclinic zirconium dioxide, the zirconium silicate powder forms a crystal boundary phase between 1170-1540°C. The dispersed zirconium silicate particles at the grain boundaries cause the remaining alumina powder to separate from the high-alumina glass phase formed by the decomposition of silica at high temperatures and the high-alumina glass phase formed after cooling, forming a discontinuous high-alumina glass phase. This creates a composite grain boundary phase of "mullite phase-discontinuous high-alumina glass phase-zirconia silicate particles," which also helps to prevent the formation of a continuous glass phase in the refractory crucible at high temperatures, thereby improving the high-temperature strength and thermal shock resistance of the refractory crucible. Furthermore, the refractory crucible in this embodiment experiences conditions similar to sintering conditions during the smelting of metals, similar to cyclically undergoing sintering conditions. Therefore, the refractory crucible in this embodiment also possesses the aforementioned advantages during use.

[0057] It should be noted that during the smelting of metals using refractory crucibles, when the sintering temperature is between 1170℃ and 1540℃, the zirconium silicate powder does not decompose to form silicon dioxide and monoclinic zirconium dioxide. In addition, when the sintering temperature is above 1540℃ for a short period of time, some zirconium silicate powder may not completely decompose to form silicon dioxide and monoclinic zirconium dioxide. In this case, both dispersed zirconium silicate particles and dispersed tetragonal zirconium dioxide particles are present in the refractory crucible.

[0058] In one embodiment of this application, the preparation method further includes: Weigh out 0.5-3 parts of dispersant, 1-3 parts of initiator, and 0.5-2 parts of organic catalyst; After adding the weighed liquid carrier to the obtained mixed powder, and before ball milling until homogeneous, the preparation method further includes: Add the weighed dispersant to the obtained mixed powder; After obtaining a mixed slurry with a high solid content, and before injecting the obtained mixed slurry into the injection molding cavity of a crucible molding die for injection molding, the preparation method further includes: The weighed initiator and organic catalyst were added to the obtained mixed slurry, and the mixed slurry after adding the weighed initiator and organic catalyst was mixed evenly. Then, vacuum degassing was performed to remove air bubbles from the mixed slurry. After drying the obtained crucible green blank, and before sintering and cooling the dried crucible green blank, the preparation method further includes: The dried crucible blanks are placed in a debinding furnace for debinding to remove organic matter.

[0059] In this embodiment, by weighing 0.5-3 parts of dispersant, 1-3 parts of initiator, and 0.5-2 parts of organic catalyst, the dispersant is added to the obtained mixed powder. This dispersant helps to depolymerize and disperse the refractory slurry, eliminating localized uneven concentrations and improving its homogeneity. The dispersant also enhances the static stability of the refractory slurry, preventing the formation of a thin upper layer and a precipitated lower layer. Furthermore, the dispersant effectively reduces the overall viscosity of the refractory slurry, improving its fluidity. Further, adding the weighed initiator and organic catalyst to the obtained mixed slurry initiates a chain polymerization reaction, allowing the refractory slurry to gradually transform into a solid gel. Additionally, the appropriate amount of initiator is beneficial for influencing the polymerization reaction. The process controls the initiation speed, reaction rate, and degree of curing. A stable initiation process allows the slurry system to cross-link and cure simultaneously, reducing problems such as curing shrinkage, porosity, and cracking, and improving the density, mechanical strength, and structural stability of the cured product. In addition, the curing speed and cross-linking density of the refractory slurry can be precisely controlled by organic catalysts to avoid problems such as gel agglomeration due to excessively fast reaction and excessively long production cycles due to excessively slow reaction. Furthermore, the dried crucible green body is placed in a debinding furnace for debinding treatment to remove organic matter. During subsequent high-temperature sintering, this helps to prevent the organic matter inside the crucible green body from vaporizing and decomposing when heated, generating a large amount of gas trapped inside the crucible green body, which can easily cause defects such as cracking, bubbling, delamination, and pore voids in the crucible green body. It can also improve the density and strength of the sintered refractory crucible.

[0060] In one embodiment of this application, the dispersant is ammonium polyacrylate or any one or more of polyacrylic acid, the initiator is ammonium persulfate, and the organic catalyst is tetramethylethylenediamine.

[0061] In this embodiment, the dispersant is any one or more of ammonium polyacrylate or polyacrylic acid. Both ammonium polyacrylate and polyacrylic acid contain abundant carboxylic acid groups, which can be firmly adsorbed on the surface of the powder particles in this embodiment. Moreover, ammonium polyacrylate or polyacrylic acid can significantly reduce the viscosity of the system under the premise of high solid content of slurry, which is beneficial to improving the fluidity and leveling of slurry. In addition, ammonium polyacrylate or polyacrylic acid can be completely decomposed and volatilized in the subsequent high-temperature sintering process, leaving no metal ion residue, which is beneficial to improving the quality of the formed refractory crucible. Furthermore, the initiator is ammonium persulfate, which is convenient to improve the initiation efficiency and initiation stability, and can be completely decomposed and volatilized in the subsequent high-temperature sintering process. Furthermore, the organic catalyst is tetramethylethylenediamine, which is beneficial to ensure precise control of the curing speed and crosslinking density of refractory slurry, and is also beneficial to volatilization and decomposition and removal in the debinding process of refractory crucible preparation, without affecting the densification of refractory crucible sintering, which is beneficial to improving the quality of refractory crucible obtained by sintering.

[0062] In one embodiment of this application, the method for preparing the liquid carrier includes: Organic monomers and crosslinking agents are dissolved in deionized water and stirred evenly to prepare mixture one, wherein the mass ratio of organic monomers to crosslinking agents is (10-30):1, the total mass fraction of organic monomers and crosslinking agents in mixture one is 10%-25%, and the remainder is deionized water; A binder is added to the prepared mixture and stirred until homogeneous to obtain a liquid carrier; wherein the mass of the added binder is 3%-10% of the total mass of the weighed alumina powder, silica powder, yttrium oxide powder, and zirconium silicate powder; The obtained mixed slurry is injected into the casting cavity of the crucible molding mold for casting and then demolded. Specifically: The obtained mixed slurry is injected into the injection molding cavity of the crucible molding mold. The organic monomers are polymerized and gelled in situ to form a three-dimensional network structure, which solidifies the mixed slurry filling the injection molding cavity, and then demolding is performed.

[0063] In this embodiment, the liquid carrier contains appropriate amounts of organic monomers, crosslinkers, and binders. This facilitates the reduction of viscosity and dispersion by the organic monomers, preventing powder agglomeration and slurry stratification; the stabilization of the molecular structure by the crosslinker; and the preservation of particle suspension without sedimentation by the binder. Furthermore, the appropriate combination of organic monomers, crosslinkers, and binders ensures that the high-solid-content mixed slurry obtained by mixing the liquid carrier with the powder raw materials exhibits good fluidity and high uniformity. Further, the in-situ polymerization and gelation of the organic monomers forms a three-dimensional network structure, and the crosslinked network strengthens and reinforces the crucible green body formed by the curing of the mixed slurry, thereby improving the strength, elasticity, and deformation resistance of the crucible green body, ultimately enhancing its quality.

[0064] In one embodiment of this application, the organic monomer is any one or more of acrylamide and methacrylamide, the crosslinking agent is methylenebisacrylamide, and the binder is any one or more of polyvinyl alcohol, silica sol, or aluminum sol.

[0065] In this embodiment, the organic monomer is any one or more of acrylamide or methacrylamide. Acrylamide and methacrylamide have the advantages of high reactivity, strong hydrophilicity, crosslinkability, and good thermal stability. Furthermore, the crosslinking agent in this embodiment is methylenebisacrylamide. Methylenebisacrylamide has amide polar groups, good water solubility, and uniform dispersion in the aqueous phase. Furthermore, the binder in this embodiment is any one or more of polyvinyl alcohol, silica sol, or aluminum sol. When a high solid content mixed slurry is obtained by mixing a liquid carrier containing polyvinyl alcohol, silica sol, or aluminum sol with powder raw materials, it is beneficial to optimize the flowability of the mixed slurry. Moreover, using the obtained mixed slurry to form crucible green bodies is beneficial to improving the forming strength of the crucible green bodies. In addition, it is beneficial to reduce sintering defects in the crucible green bodies.

[0066] In one embodiment of this application, vacuum degassing is performed in a vacuum environment with a vacuum degree of -0.08 to -0.095 MPa, and the duration of vacuum degassing is 10-30 minutes. The temperature range for in-situ polymerization and gelation of organic monomers is 40-60℃, and the duration of in-situ polymerization and gelation of organic monomers is 30-120 min. The obtained crucible green blank is dried, including: In the first drying stage, the obtained crucible green blank is placed in a constant temperature and humidity space with a relative humidity of 50-80% and a temperature of 30-50℃ for drying for 12-24 hours; In the second drying stage, the obtained crucible green blank is placed in a constant temperature and humidity space with a relative humidity of 10-30% and a temperature of 30-50℃ for drying for 24-48 hours; The conditions for placing the dried crucible blank in a debinding furnace for debinding are as follows: Heating is carried out at a rate of 1-5℃ / min to a temperature of 400-600℃, and the holding time is 2-4h. The debinding atmosphere is air or argon. The dried crucible green blank is sintered and cooled, including: The dried crucible blanks are placed in a sintering furnace and sintered for 2-5 hours in an air atmosphere at a heating rate of 2-10℃ / min to a temperature of 1360-1450℃. After sintering, the crucible blanks are cooled with the furnace.

[0067] In this embodiment, vacuum degassing is performed in a vacuum environment with a vacuum degree of -0.08 to -0.095 MPa for 10-30 minutes, which is beneficial for thoroughly removing air bubbles from the mixed slurry. Furthermore, the temperature range for in-situ polymerization and gelation of the organic monomers is 40-60°C, and the duration is 30-120 minutes. This helps avoid high-temperature damage to the matrix and powder properties, prevents thermal deformation and grain coarsening, and the suitable duration of in-situ polymerization and gelation is conducive to the formation of... Uniform shape is beneficial for ensuring a dense and defect-free interior of the solidified crucible green blank. Furthermore, in this embodiment, the crucible green blank is dried through two drying stages. In the first drying stage, the crucible green blank is placed in a constant temperature and humidity space with a relative humidity of 50-80% and a temperature of 30-50℃ for 12-24 hours. The relatively high humidity and gentle environment allow the surface moisture of the crucible green blank to evaporate slowly and evenly, avoiding rapid evaporation and crusting under high temperature and low humidity conditions. The first drying stage involves placing the crucible green blank in a constant temperature and humidity space with a relative humidity of 50-80% for 12-24 hours. The green body is dried in a constant temperature and humidity environment with a relative humidity of 10-30% and a temperature of 30-50℃ for 24-48 hours. Reducing dehumidification and extending the drying time helps break down the resistance to moisture diffusion inside the green body, allowing deeply adsorbed water and pore-bound water to gradually migrate outwards and completely evaporate. Furthermore, debinding the green body at 400-600℃ for 2-4 hours in an air or argon atmosphere helps to thoroughly remove organic matter from the interior of the green body. This process helps prevent the crucible green from cracking and ensures moderate strength, while also providing conditions for high-quality sintering of the crucible green. Furthermore, the dried crucible green is placed in a sintering furnace and sintered for 2-5 hours in an air atmosphere at a heating rate of 2-10℃ / min to a temperature of 1360-1450℃. After cooling in the furnace, the particles in the sintered refractory crucible are tightly bonded, which helps improve the density, mechanical strength, and structural stability of the sintered refractory crucible.

[0068] The following examples illustrate the preparation method of a refractory crucible that can withstand repeated high temperatures and thermal shock. Example 1

[0069] This embodiment 1 provides a refractory crucible capable of withstanding repeated high-temperature thermal shock and its preparation method. The preparation method includes the following steps: Step S202: Weigh the following raw materials according to their weight proportions: 10g liquid carrier, 79.5g corundum aggregate, 10g aluminum oxide powder, 5g silicon dioxide powder, 0.5g yttrium oxide powder, and 5g zirconium silicate powder; Step S204: The weighed corundum aggregate, aluminum oxide powder, silicon dioxide powder, yttrium oxide powder and zirconium silicate powder are mixed to obtain a mixed powder. Step S206: Add the weighed liquid carrier to the obtained mixed powder, add 3g of weighed ammonium polyacrylate to the obtained mixed powder, and ball mill and mix until uniform to obtain a mixed slurry with high solid content; wherein, ammonium polyacrylate is used as a dispersant. In step S208, 3g of ammonium persulfate and 1.5g of tetramethylethylenediamine are added to the obtained mixed slurry. The mixed slurry after adding the initiator and organic catalyst is transferred to a vacuum mixer and mixed evenly. Then, it is degassed under a vacuum of -0.09 MPa for 15 minutes to remove air bubbles from the mixed slurry. Ammonium persulfate is used as an initiator and tetramethylethylenediamine is used as an organic catalyst. Step S210: The obtained mixed slurry is injected into the injection molding cavity of the crucible forming mold for injection molding and then demolded to obtain the crucible green blank. Step S212: Dry the obtained crucible green blank; Step S214: Place the dried crucible blank in a debinding furnace for debinding treatment to remove organic matter; Step S216: The dried crucible green is sintered and cooled to obtain a refractory crucible capable of withstanding multiple high-temperature thermal shocks. During high-temperature sintering, 9g of alumina powder and 4g of silica powder undergo a solid-state diffusion reaction to form a mullite phase in situ. The remaining unreacted alumina powder and some unreacted silica powder melt at high temperature to form an aluminosilicate liquid phase, which then cools to form a high-alumina glass phase. 0.4g of yttrium trioxide powder reacts with the remaining silica powder at a low temperature to form yttrium pyrosilicate. 4g of zirconium silicate powder decomposes above 1540℃ to form silica and monoclinic zirconium dioxide, and the decomposed monoclinic zirconium dioxide undergoes a phase transformation above 1170℃ to form at the grain boundaries. The tetragonal zirconia dispersed at the grain boundaries separates the remaining alumina powder from the high-alumina glass phase formed by the decomposition of silica at high temperatures and the high-alumina glass phase formed after cooling, forming a discontinuous high-alumina glass phase. The remaining yttrium oxide powder maintains the stability of tetragonal zirconia at temperatures greater than or equal to 1170℃, forming a composite grain boundary phase of "mullite phase - discontinuous high-alumina glass phase - tetragonal zirconia dispersed particles". The corundum aggregate forms a continuous three-dimensional network structure and serves as the framework for the formed composite grain boundary phase of "mullite phase - discontinuous high-alumina glass phase - tetragonal zirconia dispersed particles". Among them, the generated yttrium pyrosilicate can reduce the nucleation barrier of the mullite phase and the liquid carrier volatilizes and is removed.

[0070] In this embodiment, the method for preparing the weighed liquid carrier in step S202 includes the following steps: Step S2010: Dissolve 20g of acrylamide and 1g of methylenebisacrylamide in 79g of deionized water and stir until homogeneous to prepare a mixture; wherein acrylamide is used as an organic monomer and methylenebisacrylamide is used as a crosslinking agent. In step S2012, 400g of silica sol is added to the prepared mixture and stirred until homogeneous to prepare a liquid carrier; wherein, silica sol is used as a binder.

[0071] In this embodiment, in step S206, alumina balls are used as the ball milling medium, the ball-to-material ratio is 2.5:1, and the ball milling is carried out for 6 hours. In addition, there are many other ways to ball mill and mix until the mixture is uniform.

[0072] In this embodiment, in step S206, 3g of weighed ammonium polyacrylate is added to the obtained mixed powder, wherein the ammonium polyacrylate serves as a dispersant. It should be noted that other mixing methods can also be used in this embodiment to achieve the effect of the dispersant.

[0073] In this embodiment, step S210 specifically involves: injecting the obtained mixed slurry into the injection molding cavity of the crucible molding mold, and then placing the crucible molding mold in a 50°C constant temperature oven for 60 minutes to achieve a temperature range of 50°C for in-situ polymerization and gelation of the organic monomers, and a gelation time of 60 minutes for in-situ polymerization of the organic monomers.

[0074] In this embodiment, step S212 specifically involves placing the obtained crucible blank in a constant temperature and humidity drying oven. In the first drying stage, the humidity is controlled at 70% and the temperature at 40°C for 24 hours; in the second drying stage, the humidity is controlled at 20% and the temperature at 40°C for 48 hours.

[0075] In this embodiment, step S214 specifically involves: placing the dried crucible blank in a debinding furnace, heating it to 500°C at a heating rate of 3°C / min under an air atmosphere, and holding it at that temperature for 3 hours to remove organic matter.

[0076] In this embodiment, step S214 specifically involves placing the dried crucible blank in a sintering furnace and sintering it for 3 hours in an air atmosphere at a sintering temperature of 1400°C at a heating rate of 5°C / min. After sintering, the blank is cooled with the furnace.

[0077] The performance of the refractory crucible sample prepared in Example 1, which can withstand multiple high-temperature thermal shocks, was tested. The test results of the refractory crucible sample are as follows: High-temperature bending strength: The bending strength of the refractory crucible sample was 25.58 MPa when tested at 1560℃ using the three-point bending method.

[0078] Cyclic thermal shock resistance: The refractory crucible sample was quickly placed into a 1500℃ high-temperature furnace, held for 30 min, and then quickly removed for air quenching. This process was repeated 10 times. The flexural strength of the refractory crucible sample before and after thermal shock was tested. The initial flexural strength before thermal shock was 57.41 MPa. After 5 thermal shock cycles, the residual strength was 72.31 MPa, with a residual strength retention rate of 125.9% (an increase of 25.9% compared to before thermal shock). After 10 thermal shock cycles, the residual strength was 59.19 MPa, with a residual strength retention rate of 103.1%. One thermal shock cycle involved quickly placing the refractory crucible sample at room temperature into a 1500℃ high-temperature furnace, holding for 30 min, and then quickly removing it for air quenching and cooling for 30 min.

[0079] Microstructure analysis: Scanning electron microscopy showed that a large number of mullite whiskers were distributed at the grain boundaries of the refractory crucible sample, and tetragonal zirconia dispersed particles were uniformly distributed at the grain boundaries, forming a composite grain boundary phase of "mullite phase-discontinuous high alumina glass phase-tetragonal zirconia dispersed particles", and the corundum skeleton formed a continuous three-dimensional network structure.

[0080] Furthermore, such as Figure 2 As shown, Figure 2 This is a scanning electron microscope (SEM) image of the fracture microstructure of the refractory crucible sample containing dispersed zirconium dioxide particles obtained in Example 1. Figure 2 The scanning electron microscope image of the fracture surface of the refractory crucible sample shows that there are dispersed zirconium dioxide particles; the dispersed zirconium dioxide particles undergo a phase transformation above 1170℃ to form tetragonal zirconium dioxide dispersed at the grain boundaries.

[0081] Furthermore, such as Figure 3 As shown, Figure 3 This is a scanning electron microscope (SEM) image of the fracture microstructure of the refractory crucible sample containing mullite whiskers obtained in Example 1 of this application. Figure 3 The scanning electron microscope image of the fracture surface of the refractory crucible sample shows the distribution of mullite whiskers.

[0082] Furthermore, such as Figure 4 As shown, Figure 4 XRD patterns of the refractory crucible sample prepared in Example 1 of this application before and after thermal shock cycling; Figure 4The results show that the refractory crucible sample prepared in Example 1 of this application was mainly composed of corundum phase before thermal shock cycling, with almost no mullite peaks. As the number of thermal shock tests increased, the mullite content gradually increased. After 5 thermal shocks, semi-quantitative analysis using RIR method showed that the mullite content reached about 28%, and after 10 thermal shocks, the mullite peak content reached about 40%. This result indicates that thermal shock cycling induced a significant mullitization reaction. The thermal shock temperature of 1500℃ provided sufficient reaction kinetic conditions, allowing the incompletely reacted alumina powder and silica powder to continue to diffuse and react to form mullite. Mullite mainly forms in the grain boundary region, strengthening the grain boundaries in situ, filling structural defects before microcrack initiation, and improving the grain boundary bonding strength. This is one of the important reasons for the continuous increase in strength in the early stage of thermal shock.

[0083] Furthermore, such as Figure 5 As shown, Figure 5 SEM images of the refractory crucible sample prepared in Example 1 of this application after 0, 3, 5, and 10 thermal shocks; specifically, Figure 5 In the figures, a, b, c, and d represent SEM images after 0, 3, 5, and 10 thermal shock cycles, respectively. Before the thermal shock test, the fracture surface of the refractory crucible sample showed virtually no microcracks. After 3 thermal shock cycles, no microcracks were observed on the fracture surface. However, after 5 temperature shock cycles from room temperature to 1500℃, the thermal shock cycle caused stress concentration exceeding the local strength, resulting in microcracks. When these microcracks around the coarse sand encountered the sand particles, they deflected, diffracted, or bifurcated during propagation, thus lengthening the crack path, increasing fracture energy consumption, and improving toughness—consistent with the toughening mechanism of ceramic particles. Furthermore, the microcracks generated at this point not only did not affect the macroscopic strength of the sample but also improved the toughness of the refractory crucible sample. At this point, the flexural strength of the refractory crucible sample reached a peak of 72.31 MPa, consistent with the microcrack toughening mechanism of ceramics.

[0084] Furthermore, as the thermal shock resistance test of the refractory crucible specimens continued, the thermal shock cyclic stress generated more microcracks. After 10 tests, the number of microcracks not only increased (from two to five), but the cracks also extended further, which had a certain impact on the macroscopic strength, decreasing from a peak of 72.31 MPa to 59.19 MPa, but still not reaching the failure state. At the same time, some pores were found inside the refractory crucible specimens. Although the presence of pores would sacrifice some strength performance, these pores acted as micro-stress buffers. During thermal shock, the stress caused by material expansion could be effectively absorbed by the pores, further improving the thermal shock resistance of the refractory crucible specimens. This indicates that the refractory crucible specimens have excellent thermal shock resistance and meet the requirements for multiple uses. Example 2

[0085] This embodiment 2 provides a refractory crucible capable of withstanding repeated high-temperature thermal shock and its preparation method. The preparation method differs from that in embodiment 1 in the following steps: Weigh the following raw materials according to the following parts by weight: 10g liquid carrier, 79.5g corundum aggregate, 5g aluminum oxide powder, 3g silicon dioxide powder, 0.3g yttrium oxide powder, and 3g zirconium silicate powder.

[0086] The performance of the refractory crucible sample prepared in Example 2, which can withstand multiple high-temperature thermal shocks, was tested. The test results of the refractory crucible sample are as follows: High-temperature bending strength: The bending strength of the refractory crucible sample was 20.34 MPa when tested at 1560℃ using the three-point bending method.

[0087] Cyclic thermal shock resistance: The refractory crucible sample was quickly placed into a 1500℃ high-temperature furnace, held for 30 min, and then quickly removed for air quenching. This process was repeated 10 times. The bending strength of the refractory crucible sample before and after thermal shock was tested. The initial bending strength before thermal shock was 51.21 MPa, and the residual strength after 5 thermal shock cycles was 60.52 MPa. The residual strength after 10 thermal shock cycles was 52.18 MPa. One thermal shock cycle consisted of quickly placing the refractory crucible sample at room temperature into a 1500℃ high-temperature furnace, holding for 30 min, and then quickly removing it for air quenching and cooling for 30 min.

[0088] Microstructure analysis: Scanning electron microscopy revealed a large number of mullite whiskers distributed at the grain boundaries of the refractory crucible sample. Tetragonal zirconia particles were uniformly distributed at the grain boundaries, forming a composite grain boundary phase of "mullite phase - discontinuous high-alumina glass phase - tetragonal zirconia particles". The corundum skeleton formed a continuous three-dimensional network structure. It should be noted that the microstructure in Example 2 is similar to that in Example 1. However, no microstructure diagram of the refractory crucible sample is given in Example 2. Example 3

[0089] This embodiment 3 provides a refractory crucible capable of withstanding repeated high-temperature thermal shock and its preparation method. The preparation method differs from that of Embodiment 1 in the following steps: Weigh the following raw materials according to the following parts by weight: 10g liquid carrier, 79.5g corundum aggregate, 12g aluminum oxide powder, 8g silicon dioxide powder, 1g yttrium oxide powder, and 8g zirconium silicate powder.

[0090] The performance of the refractory crucible sample prepared in Example 3, which can withstand multiple high-temperature thermal shocks, was tested. The test results of the refractory crucible sample are as follows: High-temperature bending strength: The bending strength of the refractory crucible sample was 22.67 MPa when tested at 1560℃ using the three-point bending method.

[0091] Cyclic thermal shock resistance: The refractory crucible sample was quickly placed into a 1500℃ high-temperature furnace, held for 30 min, and then quickly removed for air quenching. This process was repeated 10 times. The bending strength of the refractory crucible sample before and after thermal shock was tested. The initial bending strength before thermal shock was 53.32 MPa, and the residual strength after 5 thermal shock cycles was 64.93 MPa. The residual strength after 10 thermal shock cycles was 55.46 MPa. One thermal shock cycle involved quickly placing the refractory crucible sample at room temperature into a 1500℃ high-temperature furnace, holding for 30 min, and then quickly removing it for air quenching and cooling for 30 min.

[0092] Microstructure analysis: Scanning electron microscopy revealed a large number of mullite whiskers distributed at the grain boundaries of the refractory crucible sample. Tetragonal zirconia particles were uniformly distributed at the grain boundaries, forming a composite grain boundary phase of "mullite phase - discontinuous high-alumina glass phase - tetragonal zirconia particles". The corundum skeleton formed a continuous three-dimensional network structure. It should be noted that the microstructure in this Example 3 is similar to that of the refractory crucible sample in Example 1. However, no microstructure diagram of the refractory crucible sample is given in this Example 3. Example 4

[0093] This embodiment 4 provides a refractory crucible capable of withstanding repeated high-temperature thermal shock and its preparation method. The preparation method differs from that of embodiment 1 in the following steps: Weigh the following raw materials according to the following parts by weight: Liquid carrier 10g, corundum aggregate 79.5g, aluminum oxide powder 10g, silicon dioxide powder 5g, yttrium oxide powder 0.5g, zirconium silicate powder 0g.

[0094] The performance of the refractory crucible sample prepared in Example 4, which can withstand multiple high-temperature thermal shocks, was tested. The test results of the refractory crucible sample are as follows: High-temperature bending strength: The bending strength of the refractory crucible sample was 16.82 MPa when tested at 1560℃ using the three-point bending method.

[0095] Cyclic thermal shock resistance: The refractory crucible sample was quickly placed into a 1500℃ high-temperature furnace, held for 30 min, and then quickly removed for air quenching. This process was repeated 10 times. The bending strength of the refractory crucible sample before and after thermal shock was tested. The initial bending strength before thermal shock was 47.43 MPa, and the residual strength after 5 thermal shock cycles was 52.32 MPa. The residual strength after 10 thermal shock cycles was 42.15 MPa. One thermal shock cycle consisted of quickly placing the refractory crucible sample at room temperature into a 1500℃ high-temperature furnace, holding for 30 min, and then quickly removing it for air quenching and cooling for 30 min.

[0096] Microstructure analysis: Scanning electron microscopy showed that there were no tetragonal zirconium dioxide dispersed particles in the grain boundaries of the refractory crucible sample. This indicates that without the addition of zirconium silicate powder, tetragonal zirconium dioxide dispersed particles cannot be formed to strengthen the grain boundaries in the refractory crucible sample, resulting in a significant decrease in high-temperature strength and thermal shock resistance. Example 5

[0097] This embodiment 5 provides a refractory crucible capable of withstanding repeated high-temperature thermal shock and its preparation method. The preparation method differs from that in embodiment 1 in the following steps: Weigh the following raw materials according to the following parts by weight: 10g liquid carrier, 79.5g corundum aggregate, 10g aluminum oxide powder, 5g silicon dioxide powder, 0g yttrium oxide powder, and 5g zirconium silicate powder.

[0098] The performance of the refractory crucible sample prepared in Example 5, which can withstand multiple high-temperature thermal shocks, was tested. The test results of the refractory crucible sample are as follows: High-temperature bending strength: The bending strength of the refractory crucible sample was 28.21 MPa when tested at 1560℃ using the three-point bending method.

[0099] Cyclic thermal shock resistance: The refractory crucible sample was quickly placed into a 1500℃ high-temperature furnace, held for 30 min, and then quickly removed for air quenching. This process was repeated 10 times. The bending strength of the refractory crucible sample before and after thermal shock was tested. The initial bending strength before thermal shock was 62.95 MPa, and the residual strength after 5 thermal shock cycles was 38.76 MPa. The residual strength after 10 thermal shock cycles was 25.43 MPa. One thermal shock cycle involved quickly placing the refractory crucible sample at room temperature into a 1500℃ high-temperature furnace, holding for 30 min, and then quickly removing it for air quenching and cooling for 30 min.

[0100] Microstructure analysis: Scanning electron microscopy showed that there were no tetragonal zirconium dioxide dispersed particles in the grain boundaries of the refractory crucible sample. This indicates that without the addition of yttrium oxide powder, no yttrium oxide powder can maintain the stability of tetragonal zirconium dioxide at temperatures greater than or equal to 1170℃. The high-temperature strength was also improved to some extent, but the thermal shock resistance was significantly reduced. Example 6

[0101] This embodiment 6 provides a refractory crucible capable of withstanding repeated high-temperature thermal shock and its preparation method. The preparation method differs from that of embodiment 1 in the following steps: Weigh the following raw materials according to the following parts by weight: 10g liquid carrier, 79.5g corundum aggregate, 10g aluminum oxide powder, 0g silicon dioxide powder, 0.5g yttrium oxide powder, and 5g zirconium silicate powder.

[0102] The performance of the refractory crucible sample prepared in Example 6, which can withstand multiple high-temperature thermal shocks, was tested. The test results of the refractory crucible sample are as follows: High-temperature bending strength: The bending strength of the refractory crucible sample was 5.23 MPa when tested at 1560℃ using the three-point bending method.

[0103] Cyclic thermal shock resistance: The refractory crucible sample was quickly placed into a 1500℃ high-temperature furnace, held for 30 min, and then quickly removed for air quenching. This process was repeated 10 times. The bending strength of the refractory crucible sample before and after thermal shock was tested. The initial bending strength before thermal shock was 55.05 MPa, and the residual strength after 5 thermal shock cycles was 61.25 MPa. The residual strength after 10 thermal shock cycles was 52.67 MPa. One thermal shock cycle involved quickly placing the refractory crucible sample at room temperature into a 1500℃ high-temperature furnace, holding for 30 min, and then quickly removing it for air quenching and cooling for 30 min.

[0104] Microstructure analysis: Scanning electron microscopy showed that there were no mullite whiskers in the grain boundaries of the refractory crucible sample, indicating that without the addition of silica powder, mullite whiskers could not be formed in the grain boundaries of the refractory crucible sample, resulting in a severe decrease in high-temperature strength.

[0105] Furthermore, the thermal shock conditions in this embodiment are similar to the process of smelting metal using a refractory crucible sample. Therefore, the refractory crucible sample in this embodiment can be smelted into metal at least 10 times.

[0106] It should be noted that Examples 4 to 6 in this embodiment are comparative examples. The refractory crucible samples prepared in Examples 1 to 6 were obtained using the three-point bending method, such as... Figure 6 As shown, the test was conducted at 1560℃. Figure 6The comparison of the flexural strength of the refractory crucible samples prepared in Examples 1 to 6 is shown; further, the residual strength changes of the refractory crucible samples prepared in Examples 1 to 6 after cyclic thermal shock at 1500℃ are shown in the figure. Figure 7 As shown.

[0107] In addition to the technical solutions disclosed in this embodiment, conventional technical solutions in this technical field can be referred to for corundum aggregate, various powders, dispersants, initiators, organic catalysts, and equipment for sintering and cooling crucible green blanks in this invention. However, these conventional technical solutions are not the focus of this invention, and will not be described in detail here.

[0108] It should be noted that the term "comprising" and its variations used in the embodiments of this application are open-ended, meaning "including but not limited to". The term "based on" means "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; and the term "some embodiments" means "at least some embodiments". The modifications of "one" and "multiple" mentioned in the embodiments of this application are illustrative and not restrictive. Those skilled in the art should understand that, unless explicitly indicated otherwise in the context, they should be understood as "one or more".

[0109] The term "embodiment" in this specification refers to a specific feature, structure, or characteristic described in connection with an embodiment that may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily imply the same embodiment, nor does it imply that it is independent of or alternative to other embodiments. The various embodiments in this specification are described in a related manner, and similar or identical parts between embodiments can be referred to mutually.

[0110] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A refractory crucible capable of withstanding repeated high-temperature thermal shock, characterized in that, It includes: The body has a receiving cavity with one open end. The body comprises the following components by weight, based on the total weight of the raw materials: The composition comprises 8-12 parts liquid carrier, 70-85 parts corundum aggregate, 5-12 parts alumina powder, 3-10 parts silica powder, 0.3-1 parts yttrium oxide powder, and 3-8 parts zirconium silicate powder. After high-temperature sintering, 4-10 parts of the alumina powder and 2-9 parts of the silica powder undergo a solid-phase diffusion reaction at high temperature to form a mullite phase in situ. The remaining unreacted alumina powder and the remaining unreacted silica powder melt at high temperature to form an aluminosilicate liquid phase, which then cools to form a high-alumina glass phase. 0.2-0.9 parts of the yttrium oxide powder react with the remaining silica powder at a temperature below a certain high temperature to form yttrium pyrosilicate. 3-8 parts of the zirconium silicate powder decompose at temperatures above 1540℃ to form silica and monoclinic zirconium dioxide. The decomposed monoclinic zirconium dioxide... Zirconium undergoes a phase transformation above 1170℃ to form tetragonal zirconia dispersed at grain boundaries. This dispersed tetragonal zirconia causes the remaining alumina powder to separate from the high-alumina glass phase formed by the decomposition of silica at high temperatures and the high-alumina glass phase formed after cooling, forming a discontinuous high-alumina glass phase. The remaining yttrium oxide powder maintains the stability of the tetragonal zirconia at temperatures greater than or equal to 1170℃, forming a composite grain boundary phase of "mullite phase - discontinuous high-alumina glass phase - tetragonal zirconia dispersed particles." The corundum aggregate forms a continuous three-dimensional network structure and serves as the framework for the formed composite grain boundary phase of "mullite phase - discontinuous high-alumina glass phase - tetragonal zirconia dispersed particles." The generated yttrium pyrosilicate lowers the nucleation barrier of the mullite phase, and the liquid carrier evaporates and removes it. Alternatively, after high-temperature sintering, 4-10 parts of the alumina powder and 2-9 parts of the silica powder undergo a solid-phase diffusion reaction at high temperature to form a mullite phase in situ. The remaining unreacted alumina powder and the remaining unreacted silica powder melt at high temperature to form an aluminosilicate liquid phase, which then forms a high-alumina glass phase after cooling. 0.3-1 parts of the yttrium oxide powder react with the remaining silica powder at a temperature below a certain high temperature to form yttrium pyrosilicate. 3-8 parts of the zirconium silicate powder form dispersed zirconium silicate particles at the grain boundaries between 1170-1540℃. The dispersed zirconium silicate particles at the grain boundaries cause the remaining alumina powder to separate from the high-alumina glass phase formed by the decomposition of silica at high temperature and the high-alumina glass phase formed after cooling, forming a discontinuous high-alumina glass phase, thus forming a "mullite phase-discontinuous high-alumina glass phase-zirconia silicate dispersed particles" composite grain boundary phase. The corundum aggregate forms a continuous three-dimensional network structure and serves as the framework for the formed "mullite phase-discontinuous high-alumina glass phase-zirconia silicate dispersed particles" composite grain boundary phase. The generated yttrium pyrosilicate can reduce the nucleation barrier of the mullite phase, and the liquid carrier evaporates and removes it.

2. The refractory crucible capable of withstanding repeated high-temperature thermal shock according to claim 1, characterized in that, The main body, based on the total weight of the raw materials, further includes the following components in parts by weight: The dispersant comprises 0.5-3 parts, the initiator comprises 1-3 parts, and the organic catalyst comprises 0.5-2 parts. The dispersant, the initiator, and the organic catalyst are decomposed and volatilized after high-temperature sintering.

3. The refractory crucible capable of withstanding repeated high-temperature thermal shock according to claim 2, characterized in that, The dispersant is any one or more of ammonium polyacrylate or polyacrylic acid, the initiator is ammonium persulfate, and the organic catalyst is tetramethylethylenediamine.

4. The refractory crucible capable of withstanding repeated high-temperature thermal shock according to claim 1, characterized in that, The particle size of the corundum aggregate is 100-1000 μm, the particle size of the alumina powder is 5-30 μm, the particle size of the silica powder is 5-30 μm, the particle size of the yttrium oxide powder is 2-10 μm, and the particle size of the zirconium silicate powder is 5-20 μm.

5. The refractory crucible capable of withstanding repeated high-temperature thermal shock according to claim 1, characterized in that, The method for preparing the liquid carrier includes: The organic monomer and the crosslinking agent are dissolved in deionized water and stirred evenly to prepare a mixture. The mass ratio of the organic monomer to the crosslinking agent is (10-30):

1. The total mass fraction of the organic monomer and the crosslinking agent in the mixture is 10%-25%, and the remainder is deionized water. A binder is added to the prepared mixture and stirred until homogeneous to prepare the liquid carrier; wherein the mass of the added binder is 3%-10% of the total mass of the weighed alumina powder, silica powder, yttrium oxide powder and zirconium silicate powder.

6. The refractory crucible capable of withstanding repeated high-temperature thermal shock according to claim 5, characterized in that, The organic monomer is any one or more of acrylamide and methacrylamide, the crosslinking agent is methylenebisacrylamide, and the binder is any one or more of polyvinyl alcohol, silica sol, or aluminum sol.

7. The refractory crucible capable of withstanding repeated high-temperature thermal shock according to claim 1, characterized in that, The temperature range of the high temperature is 1350-1420℃.

8. A method for preparing a refractory crucible capable of withstanding repeated high-temperature thermal shock, characterized in that, The preparation method includes: Weigh the following raw materials according to the following parts by weight: 8-12 parts liquid carrier, 70-85 parts corundum aggregate, 5-12 parts aluminum oxide powder, 3-10 parts silica powder, 0.3-1 parts yttrium oxide powder, and 3-8 parts zirconium silicate powder; The weighed corundum aggregate, aluminum oxide powder, silicon dioxide powder, yttrium oxide powder and zirconium silicate powder are mixed to obtain a mixed powder; The weighed liquid carrier is added to the obtained mixed powder and ball-milled until uniformly mixed to obtain a mixed slurry with high solid content; The obtained mixed slurry is injected into the injection molding cavity of the crucible forming mold for injection molding, and then demolded to obtain a crucible green blank; The obtained crucible green blank is then dried. The dried crucible green is sintered and cooled to obtain the refractory crucible capable of withstanding multiple high-temperature thermal shocks. During high-temperature sintering, 4-10 parts of alumina powder and 2-9 parts of silica powder undergo a solid-phase diffusion reaction to form a mullite phase in situ. The remaining unreacted alumina powder and the remaining unreacted silica powder melt at high temperature to form an aluminosilicate liquid phase, which then cools to form a high-alumina glass phase. 0.2-0.9 parts of yttrium oxide powder react with the remaining silica powder at a lower temperature to form yttrium pyrosilicate. 3-8 parts of zirconium silicate powder decompose at temperatures above 1540°C to form silica and monoclinic zirconium dioxide, and the decomposed monoclinic zirconium dioxide undergoes a phase transformation at temperatures above 1170°C to form… Tetragonal zirconia is dispersed at grain boundaries, causing the remaining alumina powder to separate from the high-alumina glass phase formed by the decomposition of silica at high temperature and the high-alumina glass phase formed after cooling, forming a discontinuous high-alumina glass phase. The remaining yttrium oxide powder maintains the stability of the tetragonal zirconia at a temperature greater than or equal to 1170°C, forming a composite grain boundary phase of "mullite phase-discontinuous high-alumina glass phase-tetragonal zirconia dispersed particles". The corundum aggregate forms a continuous three-dimensional network structure and serves as the framework of the formed composite grain boundary phase of "mullite phase-discontinuous high-alumina glass phase-tetragonal zirconia dispersed particles". The generated yttrium pyrosilicate can reduce the nucleation barrier of the mullite phase, and the liquid carrier evaporates and is removed. Alternatively, after high-temperature sintering, 4-10 parts of the alumina powder and 2-9 parts of the silica powder undergo a solid-phase diffusion reaction at high temperature to form a mullite phase in situ. The remaining unreacted alumina powder and the remaining unreacted silica powder melt at high temperature to form an aluminosilicate liquid phase, which then forms a high-alumina glass phase after cooling. 0.3-1 parts of the yttrium oxide powder react with the remaining silica powder at a temperature below a certain high temperature to form yttrium pyrosilicate. 3-8 parts of the zirconium silicate powder form dispersed zirconium silicate particles at the grain boundaries between 1170-1540℃. The dispersed zirconium silicate particles at the grain boundaries cause the remaining alumina powder to separate from the high-alumina glass phase formed by the decomposition of silica at high temperature and the high-alumina glass phase formed after cooling, forming a discontinuous high-alumina glass phase, thus forming a "mullite phase-discontinuous high-alumina glass phase-zirconia silicate dispersed particles" composite grain boundary phase. The corundum aggregate forms a continuous three-dimensional network structure and serves as the framework for the formed "mullite phase-discontinuous high-alumina glass phase-zirconia silicate dispersed particles" composite grain boundary phase. The generated yttrium pyrosilicate can reduce the nucleation barrier of the mullite phase, and the liquid carrier evaporates and removes it.

9. The method for preparing a refractory crucible capable of withstanding repeated high-temperature thermal shock according to claim 8, characterized in that, The preparation method further includes: Weigh out 0.5-3 parts of dispersant, 1-3 parts of initiator, and 0.5-2 parts of organic catalyst; After adding the weighed liquid carrier to the obtained mixed powder, and before ball milling until homogeneous, the preparation method further includes: Add the weighed dispersant to the obtained mixed powder; After obtaining the mixed slurry with high solid content, and before injecting the obtained mixed slurry into the injection molding cavity of the crucible molding die for injection molding, the preparation method further includes: The initiator and the organic catalyst are added to the obtained mixed slurry, and the mixed slurry after adding the initiator and the organic catalyst is mixed evenly. Then, vacuum degassing is performed to remove air bubbles from the mixed slurry. After drying the obtained crucible green blank, and before sintering and cooling the dried crucible green blank, the preparation method further includes: The dried crucible blank is placed in a debinding furnace for debinding to remove organic matter.

10. The method for preparing a refractory crucible capable of withstanding repeated high-temperature thermal shock according to claim 9, characterized in that, The dispersant is any one or more of ammonium polyacrylate or polyacrylic acid, the initiator is ammonium persulfate, and the organic catalyst is tetramethylethylenediamine.

11. The method for preparing a refractory crucible capable of withstanding repeated high-temperature thermal shock according to claim 8, characterized in that, The method for preparing the liquid carrier includes: The organic monomer and the crosslinking agent are dissolved in deionized water and stirred evenly to prepare a mixture. The mass ratio of the organic monomer to the crosslinking agent is (10-30):

1. The total mass fraction of the organic monomer and the crosslinking agent in the mixture is 10%-25%, and the remainder is deionized water. A binder is added to the prepared mixture and stirred until homogeneous to prepare the liquid carrier; wherein the mass of the added binder is 3%-10% of the total mass of the weighed alumina powder, silica powder, yttrium oxide powder, and zirconium silicate powder; The process of injecting the obtained mixed slurry into the injection molding cavity of the crucible molding mold for injection molding and then demolding is specifically as follows: The obtained mixed slurry is injected into the injection molding cavity of the crucible molding mold, where the organic monomers are polymerized and gelled in situ to form a three-dimensional network structure, causing the mixed slurry filling the injection molding cavity to solidify, and then demolding is performed.

12. The method for preparing a refractory crucible capable of withstanding repeated high-temperature thermal shock according to claim 10, characterized in that, The organic monomer is any one or more of acrylamide and methacrylamide, the crosslinking agent is methylenebisacrylamide, and the binder is any one or more of polyvinyl alcohol, silica sol, or aluminum sol.

13. The method for preparing a refractory crucible capable of withstanding repeated high-temperature thermal shock according to claim 11, characterized in that, The vacuum degassing is carried out in a vacuum environment with a vacuum degree of -0.08 to -0.095 MPa, and the vacuum degassing time is 10-30 min. The temperature range for in-situ polymerization and gelation of the organic monomer is 40-60℃, and the duration of in-situ polymerization and gelation of the organic monomer is 30-120 min. The drying process of the obtained crucible green blank includes: In the first drying stage, the obtained crucible green blank is placed in a constant temperature and humidity space with a relative humidity of 50-80% and a temperature of 30-50℃ for drying for 12-24 hours; In the second drying stage, the obtained crucible green blank is placed in a constant temperature and humidity space with a relative humidity of 10-30% and a temperature of 30-50℃ for drying for 24-48 hours; The conditions for placing the dried crucible blank in a debinding furnace for debinding treatment are as follows: Heating is carried out at a rate of 1-5℃ / min to a temperature of 400-600℃, and the holding time is 2-4h. The debinding atmosphere is air or argon. The sintering and cooling of the dried crucible green blank includes: The dried crucible blank is placed in a sintering furnace and sintered for 2-5 hours in an air atmosphere at a sintering temperature of 1360-1450°C, which is increased at a heating rate of 2-10°C / min. After sintering, the crucible blank is cooled with the furnace.

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