Densified, impermeable zirconia refractory and method of making same

Abstract

The present application belongs to the technical field of zirconia refractory parts, and particularly relates to a densified anti-infiltration zirconia refractory part and a manufacturing method thereof. The present application is prepared by using specific components and dosages of raw materials, and through the steps of pretreatment, mixing, loading forming, sintering and post-treatment. Through gradient structure design, grain boundary regulation and surface defect repair, the prepared zirconia refractory part has high bulk density (≥5.76 g / cm³), low apparent porosity (≤0.36%), high bending strength (≥535 MPa) and excellent resistance to glass liquid infiltration (erosion depth ≤0.2 mm). The gradient structure reduces the interface stress and inhibits the phase transition of ZrO2, the rare earth oxide addition forms a high-viscosity glass phase to block the diffusion path of erosive ions, the molten salt impregnation process improves the material density and durability, and the present application meets the demand of modern industry for high-performance refractory materials.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of zirconia refractory parts, and particularly relates to a densified anti-permeation zirconia refractory part and a manufacturing method thereof. BACKGROUND

[0002] In many high-temperature process flows of modern industry, refractory materials play an indispensable key role. From blast furnaces and converter furnaces in steel smelting to melting furnaces in glass manufacturing, to kilns in ceramic firing and many other equipment, excellent performance of refractory materials is relied on to resist high temperature, corrosion, erosion and other severe working conditions, to ensure the smooth progress of the production process and the service life of the equipment. The performance of refractory materials is directly related to the efficiency of industrial production, product quality, energy consumption and many other important aspects.

[0003] Zirconia (ZrO2) refractory material is widely used in many fields due to its unique excellent performance. It has a very high melting point (about 2715℃), good thermal shock resistance, excellent chemical corrosion resistance and high mechanical strength. These characteristics enable it to resist the erosion of high-temperature flames, molten metals or glass liquids in some extremely harsh high-temperature environments, such as glass melting furnaces, continuous casting tundishes in the steel industry and high-temperature sintering furnaces in the electronics industry, maintain the integrity and stability of the structure, and thus provide reliable protection for related industrial production.

[0004] Although traditional zirconia refractory materials have shown many advantages, with the continuous development and progress of modern industrial technology, the performance requirements of refractory materials are also increasing. The common zirconia refractory materials on the market still have some problems to be solved. On the one hand, its volume stability at high temperature still needs to be improved, and it is easy to appear micro-cracks or even peeling phenomenon during long-term high-temperature use, which affects its service life and reliability. On the other hand, the anti-permeation performance of traditional zirconia refractory materials is not ideal when facing glass melt and other materials, which can easily lead to the destruction of the internal structure of the material, and thus cause a series of production failures, increase the maintenance cost and production risk of enterprises.

[0005] In order to overcome the limitations of the above-mentioned traditional zirconia refractory materials, various modification methods and technical means have been actively explored in the industry. For example, by adding different oxides or compounds to optimize its microstructure, improve its high temperature stability and corrosion resistance; using complex forming process or sintering technology, improving the density and uniformity of the material; and surface treatment of the material. However, how to realize the synergistic improvement of multiple properties, such as simultaneously increasing the bulk density, reducing the apparent porosity, enhancing the bending strength and glass liquid permeability, etc., is still a challenging problem. In addition, how to improve the performance of the material while ensuring the feasibility, economy and stability of the preparation process is also an important factor that cannot be ignored in actual production. SUMMARY

[0006] In view of the deficiencies of the prior art, the present application provides a densified anti-permeation zirconia refractory and a manufacturing method thereof, aiming to prepare a zirconia refractory with high bulk density, low apparent porosity, high bending strength and excellent glass liquid permeability, to meet the urgent needs of modern industry for high-performance refractory materials, and to provide more reliable, durable and economically efficient refractory material solutions for industrial production.

[0007] The first aspect of the present application is to provide a manufacturing method of a densified anti-permeation zirconia refractory, comprising:

[0008] Selecting base powder raw materials including the following components and amounts:

[0009]

[0010] Pretreating the raw materials:

[0011] Grinding zirconia, single crystal alumina, fused quartz powder, boron compound and rare earth oxide to a predetermined particle size respectively; after calcining the silicon carbide whiskers to remove surface impurities, surface modification treatment is carried out with silane coupling agent to improve dispersibility;

[0012] Mixing the raw materials:

[0013] The matrix layer mixture is mixed by zirconia, single crystal alumina, fused quartz powder, boron compound, rare earth oxide, silicon carbide whiskers, nano-alumina and nano-zirconia according to the formula amount;

[0014] The surface layer mixture is additionally added with 3-8% mass of nano-Y2Si2O7 powder based on the formula of the matrix layer;

[0015] Loading and forming the raw materials:

[0016] Fill the mold with the base layer mixture to a thickness of 90-95% of the total thickness, and then fill it with the surface layer mixture to a thickness of 5-10% of the total thickness; after filling, cold isostatic pressing is performed;

[0017] Sintering the formed green body:

[0018] The formed green body is pre-sintered to remove the binder, and then gas pressure sintered under a protective atmosphere. The sintered green body is then hot isostatically pressed to further eliminate internal defects and improve material density.

[0019] Post-processing of sintered parts:

[0020] The sintered part is subjected to molten salt impregnation and plasma spraying treatment to obtain a densified and impermeable zirconia refractory part.

[0021] As a further optimization scheme for the above-mentioned method of manufacturing densified impermeability-proof zirconia refractory parts, during the pretreatment of the raw materials, zirconium dioxide, single-crystal alumina, fused quartz powder, boron compound and rare earth oxide are respectively ground to a particle size D50 ≤ 0.8 μm, and 0.2% of the mass of the powder is added as a dispersant during the grinding process; during the surface modification treatment of silicon carbide whiskers with a silane coupling agent, the concentration of the silane coupling agent used is 2-5%, and the amount used is 5-8% of the mass of the silicon carbide whiskers.

[0022] As a further optimization scheme of the above-mentioned densified impermeability-proof zirconia refractory manufacturing method, when preparing the surface layer mixture, 5% by mass of nano Y2Si2O7 powder is additionally added to the surface layer mixture on the basis of the matrix layer formula.

[0023] As a further optimization scheme for the above-mentioned method of manufacturing densified impermeability-proof zirconia refractory parts, when preparing the base layer mixture, a magnesium dihydrogen phosphate solution with a concentration of 15-20% is added during the mixing process, and the amount of magnesium dihydrogen phosphate solution added is 10-20% of the total mass of the raw materials; when preparing the surface layer mixture, a magnesium dihydrogen phosphate solution with a concentration of 15-20% is added during the mixing process, and the amount of magnesium dihydrogen phosphate solution added is 10-20% of the total mass of the raw materials.

[0024] As a further optimization scheme for the above-mentioned method for manufacturing densified impermeable zirconia refractory parts, during the raw material filling and molding process, the cold isostatic pressing pressure is 250-350 MPa, and the holding time is 2-5 minutes.

[0025] As a further optimization of the above-mentioned densification anti-penetration zirconia refractory manufacturing method, during the sintering process of the formed green body, the formed green body is pre-sintered at 780-820℃ for 1-5 hours, with a heating rate of 2-4℃ / min, to remove the binder; then, pressure sintering is carried out at 1600-1700℃ for 1-3 hours, with the introduction of 8-12MPa nitrogen, and a heating rate of 4-6℃ / min; and then the sintered green body is subjected to hot isostatic pressing at 1400-1600℃, 120-180MPa in an argon environment for 0.8-1.5 hours, with a cooling rate controlled at ≤5℃ / min, to further eliminate internal defects and improve material density.

[0026] As a further optimization of the above-mentioned densification anti-penetration zirconia refractory manufacturing method, the oxygen content in the atmosphere used for pre-sintering and pressure sintering is ≤10ppm.

[0027] As a further optimization of the above-mentioned densification anti-penetration zirconia refractory manufacturing method, during the post-processing of the sintered piece, the sintered piece is immersed in molten borosilicate glass at 1200-1250℃ for 25-40 minutes to fill the surface pores; after the immersion is completed, the surface residual glass phase is naturally cooled and removed.

[0028] As a further optimization of the above-mentioned densification anti-penetration zirconia refractory manufacturing method, during the post-processing of the sintered piece, after molten salt immersion, a plasma spray is used to deposit a 30-50μm Al2O3-YAG composite coating on the surface.

[0029] The second aspect of the present application is to provide a densification anti-penetration zirconia refractory, which is prepared according to the above-mentioned manufacturing method.

[0030] Advantages

[0031] The present application significantly improves the comprehensive performance of zirconia refractory through gradient structure design, grain boundary control and surface defect repair. The prepared zirconia refractory has high bulk density (≥5.76g / cm 3 ), low apparent porosity (≤0.36%), high bending strength (≥535MPa) and excellent glass liquid penetration resistance (erosion depth ≤0.2mm). Among them, the gradient structure effectively reduces the interfacial stress and inhibits the phase transition of ZrO2, while the addition of rare earth oxides forms a high-viscosity glass phase, blocking the diffusion path of erosive ions, further enhancing the erosion resistance of the material. In addition, the molten salt immersion process significantly reduces the surface open porosity, improving the density and durability of the material. DETAILED DESCRIPTION

[0032] The application will be further clarified by the following examples which are intended to be exemplary of the present application, which is not limited to them. Examples

[0033] (I) Raw materials and their specifications

[0034] Table 1 Raw materials and their specifications

[0035]

[0036]

[0037] (II) Base powder raw materials and their amounts

[0038]

[0039] (III) Preparation process steps

[0040] 1. Raw material pretreatment

[0041] Raw material pretreatment includes grinding, sieving and surface treatment of silicon carbide whiskers. First, zirconia, single crystal alumina, fused quartz powder, boron compounds and rare earth oxides are ground to the target particle size (D50≤0.8 μm) respectively. High-energy ball milling is used for grinding and dispersion treatment, the ball mill speed is 300 rpm, the ball-to-material ratio is 5:1, and 0.2% polyacrylic acid is added as a dispersant, the ball milling time is 4 hours. All raw materials need to be sieved after grinding to ensure uniform particle size. For silicon carbide whiskers, first calcined at 800°C for 2 hours to remove surface impurities, then surface modification treatment with silane coupling agent (KH550) to improve its dispersibility in the subsequent mixing process. The concentration of silane coupling agent is 2-5% (mass fraction), and the amount is 5-8% of the mass of silicon carbide whiskers.

[0042] 2. Mixing raw materials

[0043] Mixing raw materials is divided into the preparation of matrix layer mixture and surface layer mixture. The matrix layer mixture is mixed by zirconia, single crystal alumina, fused quartz powder, boron compounds, rare earth oxides, silicon carbide whiskers, nano-alumina and nano-zirconia according to the formula amount. During the mixing process, 15-20% magnesium dihydrogen phosphate solution is added, the amount of magnesium dihydrogen phosphate solution added is 10-20% of the total mass of raw materials, wet ball milling for 6 hours to form a uniform slurry. The slurry is dried at 80°C for 12 hours and then sieved through a 100 mesh sieve for use.

[0044] The surface layer mixture is based on the base layer formula, with an additional 5% by weight of nano-Y2Si2O7 powder added. During mixing, a 15-20% magnesium dihydrogen phosphate solution is added, with the amount of magnesium dihydrogen phosphate added being 10-20% of the total weight of the raw materials. The mixture is wet-milled for 6 hours to form a uniform slurry. The slurry is dried at 80°C for 12 hours and then passed through a 100-mesh sieve for later use.

[0045] 3. Molding

[0046] The molding process utilizes layered filling and cold isostatic pressing techniques. First, the mold is filled with the base layer mixture to a thickness of 90-95% of the total thickness, followed by the surface layer mixture to a thickness of 5-10% of the total thickness. After filling, cold isostatic pressing is used at a pressure of 300 MPa and a holding time of 3 minutes to ensure the compactness and uniformity of the green body.

[0047] 4. Sintering

[0048] The sintering process includes three steps: pre-sintering, gas pressure sintering and hot isostatic pressing. First, the formed body is pre-sintered at 800°C for 2 hours with a heating rate of 3°C / min to remove the binder. Subsequently, gas pressure sintering is carried out at 1600-1700°C for 2 hours, 10MPa of nitrogen is introduced, and the heating rate is 5°C / min. Finally, the sintered body is hot isostatically pressed in an argon environment at 1500°C and 150MPa for 1 hour, and the cooling rate is controlled at ≤5°C / min to further eliminate internal defects and increase the density of the material. The atmosphere for pre-sintering and gas pressure sintering uses high-purity inert gas (nitrogen or argon) with an oxygen content of ≤10ppm.

[0049] 5. Post-processing

[0050] Post-processing involves two steps: molten salt impregnation and plasma spraying. First, the sintered component is immersed in molten borosilicate glass at 1200-1250°C for 30 minutes to fill the surface pores. After impregnation, the component is allowed to cool naturally and any remaining glass phase on the surface is removed. Subsequently, a 30-50μm thick Al2O3-YAG composite coating is deposited on the surface using plasma spraying. The spraying parameters are: current 500A, gas flow rate Ar / H2 = 45 / 15 SLPM, spray distance 80mm, and spray speed 200mm / s. This results in a densified, impermeable zirconia refractory component.

[0051] Example 1

[0052] Basic powder raw materials and their dosage

[0053]

[0054]

[0055] 1. Raw material pretreatment

[0056] The raw material pretreatment includes grinding, sieving and surface treatment of silicon carbide whiskers. Firstly, zirconia, single crystal alumina, fused quartz powder, boron compounds and rare earth oxides are ground to the target particle size (D50≤0.8 μm) respectively. High-energy ball milling is used for grinding and dispersion treatment, the ball mill speed is 300 rpm, the ball-to-material ratio is 5:1, and 0.2% polyacrylic acid is added as a dispersant, and the ball milling time is 4 hours. All raw materials need to be sieved after grinding to ensure uniform particle size. For silicon carbide whiskers, first calcined at 800°C for 2 hours to remove surface impurities, then surface modification treatment with silane coupling agent (KH550) to improve its dispersibility in the subsequent mixing process. The concentration of silane coupling agent is 2% (mass fraction), and the amount is 5% of the mass of silicon carbide whiskers.

[0057] 2. Mixing raw materials

[0058] The mixing of raw materials is divided into the preparation of matrix layer mixture and surface layer mixture. The matrix layer mixture is mixed by zirconia, single crystal alumina, fused quartz powder, boron compounds, rare earth oxides, silicon carbide whiskers, nano-alumina and nano-zirconia according to the formula amount. Add 18% magnesium dihydrogen phosphate solution during mixing, the amount of magnesium dihydrogen phosphate solution added is 15% of the total mass of raw materials, wet ball milling for 6 hours to form a uniform slurry. After drying the slurry at 80°C for 12 hours, pass through a 100 mesh sieve for use.

[0059] The surface layer mixture is additionally added with 5% mass of nano-Y2Si2O7 powder based on the matrix layer formula, and 18% magnesium dihydrogen phosphate solution is added during mixing. The amount of magnesium dihydrogen phosphate solution added is 15% of the total mass of raw materials, wet ball milling for 6 hours to form a uniform slurry. After drying the slurry at 80°C for 12 hours, pass through a 100 mesh sieve for use.

[0060] 3. Forming

[0061] The forming process adopts layered filling and cold isostatic pressing forming technology. First, fill the matrix layer mixture in the mold, the thickness is 90% of the total thickness, then fill the surface layer mixture, the thickness is 10% of the total thickness. After filling, cold isostatic pressing is used, the pressure is 300 MPa, and the holding time is 3 minutes to ensure the density and uniformity of the green body.

[0062] 4. Sintering

[0063] The sintering process includes three steps: pre-sintering, gas pressure sintering and hot isostatic pressing. First, the green body is pre-sintered at 800°C for 2 hours with a heating rate of 3°C / min to remove the binder. Subsequently, the gas pressure sintering is performed at 1600°C for 2 hours with a heating rate of 5°C / min under 10 MPa nitrogen atmosphere. Finally, the sintered body is subjected to hot isostatic pressing at 1500°C under 150 MPa argon atmosphere for 1 hour with a cooling rate of ≤5°C / min to further eliminate internal defects and improve material density. High-purity inert gas (nitrogen or argon) is used for pre-sintering and gas pressure sintering atmospheres, with oxygen content ≤10 ppm.

[0064] 5. Post-processing

[0065] The post-processing includes two steps: molten salt impregnation and plasma spraying. First, the sintered piece is immersed in 1200°C molten borosilicate glass for 30 minutes to fill the surface pores. After impregnation, the surface residual glass phase is naturally cooled and removed. Subsequently, a 30 μm Al2O3-YAG composite coating is deposited on the surface using plasma spraying technology, with the following spraying parameters: current 500 A, gas flow Ar / H2 = 45 / 15 SLPM, spraying distance 80 mm, and spraying speed 200 mm / s. A densified impermeable zirconia refractory piece is obtained.

[0066] Example 2

[0067] Basic powder raw materials and their amounts

[0068]

[0069] 1. Raw material pretreatment

[0070] The raw material pretreatment includes grinding, sieving and surface treatment of silicon carbide whiskers. First, the zirconia, single crystal alumina, fused quartz powder, boron compounds and rare earth oxides are ground to the target particle size (D50 ≤ 0.8 μm) respectively. High-energy ball milling is used for grinding and dispersion treatment, with a ball mill speed of 300 rpm, a ball-to-material ratio of 5:1, and the addition of 0.2% polyacrylic acid as a dispersant, and the ball milling time is 4 hours. All raw materials need to be sieved after grinding to ensure uniform particle size. For silicon carbide whiskers, first calcined at 800°C for 2 hours to remove surface impurities, and then surface modified with silane coupling agent (KH550) to improve its dispersibility in the subsequent mixing process. The concentration of silane coupling agent is 5% (mass fraction), and the amount is 8% of the mass of silicon carbide whiskers.

[0071] 2. Mixing raw materials

[0072] The raw materials are mixed into two parts, the matrix layer mixture and the surface layer mixture. The matrix layer mixture is made by mixing zirconia, single crystal alumina, fused quartz powder, boron compound, rare earth oxide, silicon carbide whisker, nano-alumina and nano-zirconia according to the formula. During the mixing process, 18% magnesium dihydrogen phosphate solution is added, the amount of magnesium dihydrogen phosphate solution added is 15% of the total mass of the raw materials, wet ball milling is used for 6 hours to form a uniform slurry. The slurry is dried at 80°C for 12 hours and then sieved through a 100 mesh sieve for use.

[0073] The surface layer mixture is additionally added with 5% mass of nano-Y2Si2O7 powder based on the matrix layer formula. During the mixing process, 18% magnesium dihydrogen phosphate solution is added, the amount of magnesium dihydrogen phosphate solution added is 15% of the total mass of the raw materials, wet ball milling is used for 6 hours to form a uniform slurry. The slurry is dried at 80°C for 12 hours and then sieved through a 100 mesh sieve for use.

[0074] 3. Forming

[0075] The forming process uses layered filling and cold isostatic pressing technology. First, the matrix layer mixture is filled in the mold, the thickness is 95% of the total thickness, then the surface layer mixture is filled, the thickness is 5% of the total thickness. After filling, cold isostatic pressing is used, the pressure is 300 MPa, the holding time is 3 minutes to ensure the density and uniformity of the green body.

[0076] 4. Sintering

[0077] The sintering process includes three steps of pre-sintering, pressure sintering and hot isostatic pressing. First, the formed green body is pre-sintered at 800°C for 2 hours, the heating rate is 3°C / min to remove the binder. Then, pressure sintering is carried out at 1700°C for 2 hours, 10 MPa of nitrogen gas is introduced, the heating rate is 5°C / min. Finally, the sintered green body is treated by hot isostatic pressing at 1500°C, 150 MPa in an argon environment for 1 hour, the cooling rate is controlled at ≤5°C / min to further eliminate internal defects and improve the material density. The atmosphere for pre-sintering and pressure sintering uses high-purity inert gas (nitrogen or argon), the oxygen content is ≤10 ppm.

[0078] 5. Post-processing

[0079] The post-treatment includes two steps of molten salt impregnation and plasma spraying. Firstly, the sintered part is immersed in molten borosilicate glass at 1250℃ for 30 minutes to fill the surface pores. After the impregnation is completed, the surface residual glass phase is removed by natural cooling. Subsequently, a 50μm Al2O3-YAG composite coating is deposited on the surface by plasma spraying technology, and the spraying parameters are: current 500A, gas flow Ar / H2=45 / 15 SLPM, spraying distance 80mm, spraying speed 200mm / s. A densified anti-permeation zirconia refractory part is prepared.

[0080] Example 3

[0081] Basic powder raw materials and their amounts

[0082]

[0083] 1. Raw material pretreatment

[0084] The raw material pretreatment includes grinding, sieving and surface treatment of silicon carbide whiskers. Firstly, the zirconia, single crystal alumina, fused quartz powder, boron compound and rare earth oxide are ground to the target particle size (D50≤0.8μm) respectively. High-energy ball milling is used for grinding and dispersion treatment, the ball mill speed is 300rpm, the ball-to-material ratio is 5:1, and 0.2% polyacrylic acid is added as a dispersant, and the ball milling time is 4 hours. All raw materials need to be sieved after grinding to ensure uniform particle size. For silicon carbide whiskers, first calcined at 800℃ for 2 hours to remove surface impurities, and then surface modification treatment with silane coupling agent (KH550) to improve its dispersibility in the subsequent mixing process. The concentration of silane coupling agent is 5% (mass fraction), and the amount is 5% of the mass of silicon carbide whiskers.

[0085] 2. Mixing raw materials

[0086] The mixing of raw materials is divided into the preparation of the matrix layer mixture and the surface layer mixture. The matrix layer mixture is mixed by zirconia, single crystal alumina, fused quartz powder, boron compound, rare earth oxide, silicon carbide whiskers, nano-alumina and nano-zirconia according to the formula amount. During the mixing process, 15% magnesium dihydrogen phosphate solution is added, the amount of magnesium dihydrogen phosphate solution added is 20% of the total mass of raw materials, wet ball milling for 6 hours to form a uniform slurry. After the slurry is dried at 80℃ for 12 hours, it is sieved through a 100 mesh sieve for use.

[0087] The surface layer mixture is additionally added with 5% mass of nano Y2Si2O7 powder based on the matrix layer formula, and 20% magnesium dihydrogen phosphate solution is added during the mixing process, the amount of magnesium dihydrogen phosphate solution added is 20% of the total mass of raw materials, wet ball milling for 6 hours to form a uniform slurry. After the slurry is dried at 80℃ for 12 hours, it is sieved through a 100 mesh sieve for use.

[0088] 3. Molding

[0089] The molding process utilizes layered filling and cold isostatic pressing techniques. First, the mold is filled with the base layer mixture to a thickness of 90% of the total thickness, followed by the surface layer mixture to a thickness of 10% of the total thickness. After filling, cold isostatic pressing is used at a pressure of 300 MPa and a holding time of 3 minutes to ensure the compactness and uniformity of the green body.

[0090] 4. Sintering

[0091] The sintering process includes three steps: pre-sintering, gas pressure sintering and hot isostatic pressing. First, the formed body is pre-sintered at 800°C for 2 hours with a heating rate of 3°C / min to remove the binder. Subsequently, gas pressure sintering is carried out at 1650°C for 2 hours, 10MPa of nitrogen is introduced, and the heating rate is 5°C / min. Finally, the sintered body is hot isostatically pressed at 1500°C and 150MPa in an argon environment for 1 hour, and the cooling rate is controlled at ≤5°C / min to further eliminate internal defects and increase the density of the material. The atmosphere for pre-sintering and gas pressure sintering uses high-purity inert gas (nitrogen or argon) with an oxygen content of ≤10ppm.

[0092] 5. Post-processing

[0093] Post-processing involves two steps: molten salt impregnation and plasma spraying. First, the sintered component is immersed in molten borosilicate glass at 1250°C for 30 minutes to fill the surface pores. After impregnation, the component is allowed to cool naturally, and any remaining glass phase on the surface is removed. Subsequently, a 50μm thick Al2O3-YAG composite coating is deposited on the surface using plasma spraying. The spraying parameters are: current 500A, gas flow rate Ar / H2 = 45 / 15 SLPM, spray distance 80mm, and spray speed 200mm / s. This results in a densified, impermeable zirconia refractory component.

[0094] Example 4

[0095] Basic powder raw materials and their dosage

[0096]

[0097] 50 parts by mass of rare earth oxide;

[0098] 30 parts by mass of silicon carbide whiskers;

[0099] 80 parts by mass of nano-alumina;

[0100] 30 parts by mass of nano zirconium oxide.

[0101] 1. Raw material pretreatment

[0102] The raw material pretreatment includes grinding, screening and surface treatment of silicon carbide whiskers. First, zirconia, single crystal alumina, fused quartz powder, boron compounds and rare earth oxides are ground to the target particle size (D50≤0.8 μm) respectively. High-energy ball mill is used for grinding and dispersion treatment, the ball mill speed is 300 rpm, the ball-to-material ratio is 5:1, and 0.2% polyacrylic acid is added as a dispersant, and the ball milling time is 4 hours. All raw materials need to be screened after grinding to ensure uniform particle size. For silicon carbide whiskers, first calcined at 800°C for 2 hours to remove surface impurities, then surface modification treatment with silane coupling agent (KH550) to improve its dispersibility in the subsequent mixing process. The concentration of silane coupling agent is 5% (mass fraction), and the amount is 5% of the mass of silicon carbide whiskers.

[0103] 2. Mixing raw materials

[0104] The mixed raw materials are divided into the preparation of the matrix layer mixture and the surface layer mixture. The matrix layer mixture is mixed by zirconia, single crystal alumina, fused quartz powder, boron compounds, rare earth oxides, silicon carbide whiskers, nano-alumina and nano-zirconia according to the formula amount. Add 15% magnesium dihydrogen phosphate solution during mixing, the amount of magnesium dihydrogen phosphate solution is 10% of the total mass of raw materials, wet ball milling for 6 hours to form a uniform slurry. The slurry is dried at 80°C for 12 hours and then sieved through a 100 mesh sieve for use.

[0105] The surface layer mixture is additionally added with 5% mass of nano-Y2Si2O7 powder based on the matrix layer formula. Add 20% magnesium dihydrogen phosphate solution during mixing, the amount of magnesium dihydrogen phosphate solution is 20% of the total mass of raw materials, wet ball milling for 6 hours to form a uniform slurry. The slurry is dried at 80°C for 12 hours and then sieved through a 100 mesh sieve for use.

[0106] 3. Forming

[0107] The forming process adopts layered filling and cold isostatic pressing forming technology. First, fill the matrix layer mixture in the mold, the thickness is 95% of the total thickness, then fill the surface layer mixture, the thickness is 5% of the total thickness. After filling, cold isostatic pressing is used, the pressure is 300 MPa, and the holding time is 3 minutes to ensure the density and uniformity of the green body.

[0108] 4. Sintering

[0109] The sintering process includes three steps of pre-sintering, gas pressure sintering and hot isostatic pressing. First, the shaped body is pre-sintered at 800°C for 2 hours with a heating rate of 3°C / min to remove the binder. Subsequently, the gas pressure sintering is performed at 1600°C for 2 hours with a nitrogen gas of 10 MPa and a heating rate of 5°C / min. Finally, the sintered body is subjected to hot isostatic pressing at 1500°C and 150 MPa in an argon atmosphere for 1 hour with a cooling rate of ≤5°C / min to further eliminate internal defects and improve the material density. High-purity inert gas (nitrogen or argon) is used for the atmosphere of pre-sintering and gas pressure sintering, and the oxygen content is ≤10 ppm.

[0110] 5. Post-processing

[0111] The post-processing includes two steps of molten salt immersion and plasma spraying. First, the sintered part is immersed in molten borosilicate glass at 1250°C for 30 minutes to fill the surface pores. After immersion, the surface residual glass phase is naturally cooled and removed. Subsequently, a 30 μm Al2O3-YAG composite coating is deposited on the surface by plasma spraying technology, with the spraying parameters being: current 500 A, gas flow Ar / H2 = 45 / 15 SLPM, spraying distance 80 mm, and spraying speed 200 mm / s. A densified and impermeable zirconia refractory part is prepared.

[0112] Example 5

[0113] Basic powder raw materials and their amounts

[0114] Zirconia 1150 parts by mass;

[0115] Single-crystal powdered alumina 255 parts by mass;

[0116] Fused quartz powder 150 parts by mass;

[0117] Boron compound 75 parts by mass;

[0118] Rare earth oxide 50 parts by mass;

[0119] Silicon carbide whisker 30 parts by mass;

[0120] Nano-alumina 80 parts by mass;

[0121] Nano-zirconia 30 parts by mass.

[0122] 1. Raw material pretreatment

[0123] Raw material pretreatment includes grinding, sieving and surface treatment of silicon carbide whiskers. First, zirconia, single crystal alumina, fused quartz powder, boron compounds and rare earth oxides are ground to the target particle size (D50≤0.8 μm) respectively. High-energy ball milling is used for grinding and dispersion treatment, the ball mill speed is 300 rpm, the ball-to-material ratio is 5:1, and 0.2% polyacrylic acid is added as a dispersant, the ball milling time is 4 hours. All raw materials need to be sieved after grinding to ensure uniform particle size. For silicon carbide whiskers, first calcined at 800°C for 2 hours to remove surface impurities, then surface modification treatment with silane coupling agent (KH550) to improve its dispersibility in the subsequent mixing process. The concentration of silane coupling agent is 2% (mass fraction), and the amount is 5% of the mass of silicon carbide whiskers.

[0124] 2. Mixing raw materials

[0125] The preparation of the mixed raw materials is divided into the preparation of the matrix layer mixture and the surface layer mixture. The matrix layer mixture is mixed by zirconia, single crystal alumina, fused quartz powder, boron compounds, rare earth oxides, silicon carbide whiskers, nano-alumina and nano-zirconia according to the formula amount. During the mixing process, 15% magnesium dihydrogen phosphate solution is added, the amount of magnesium dihydrogen phosphate solution added is 10% of the total mass of raw materials, wet ball milling for 6 hours to form a uniform slurry. After the slurry is dried at 80°C for 12 hours, it is sieved through a 100 mesh sieve for use.

[0126] The surface layer mixture is additionally added with 5% mass of nano-Y2Si2O7 powder based on the matrix layer formula, 15% magnesium dihydrogen phosphate solution is added during the mixing process, the amount of magnesium dihydrogen phosphate solution added is 10% of the total mass of raw materials, wet ball milling for 6 hours to form a uniform slurry. After the slurry is dried at 80°C for 12 hours, it is sieved through a 100 mesh sieve for use.

[0127] 3. Forming

[0128] The forming process adopts the technology of layered filling and cold isostatic pressing. First, the matrix layer mixture is filled in the mold, the thickness is 95% of the total thickness, then the surface layer mixture is filled, the thickness is 5% of the total thickness. After filling, cold isostatic pressing is used, the pressure is 300 MPa, the holding time is 3 minutes to ensure the density and uniformity of the green body.

[0129] 4. Sintering

[0130] The sintering process includes three steps: pre-sintering, gas pressure sintering and hot isostatic pressing. First, the green body is pre-sintered at 800°C for 2 hours with a heating rate of 3°C / min to remove the binder. Then, the pre-sintered body is subjected to gas pressure sintering at 1700°C for 2 hours under 10 MPa nitrogen with a heating rate of 5°C / min. Finally, the sintered body is subjected to hot isostatic pressing at 1500°C under 150 MPa argon for 1 hour with a cooling rate of ≤5°C / min to further eliminate internal defects and improve material density. High-purity inert gas (nitrogen or argon) is used as the atmosphere for pre-sintering and gas pressure sintering, with an oxygen content of ≤10 ppm.

[0131] 5. Post-processing

[0132] The post-processing includes two steps: molten salt immersion and plasma spraying. First, the sintered part is immersed in molten borosilicate glass at 1200°C for 30 minutes to fill the surface pores. After immersion, the surface residual glass phase is naturally cooled and removed. Then, a 30 μm Al2O3-YAG composite coating is deposited on the surface using plasma spraying technology, with the following spraying parameters: current 500 A, gas flow Ar / H2 = 45 / 15 SLPM, spraying distance 80 mm, and spraying speed 200 mm / s. A densified and impermeable zirconia refractory part is obtained.

[0133] Example 6

[0134] Basic powder raw materials and their amounts

[0135]

[0136] 1. Raw material pretreatment

[0137] The raw material pretreatment includes grinding, sieving and surface treatment of silicon carbide whiskers. First, the zirconia, single crystal alumina, fused quartz powder, boron compounds and rare earth oxides are ground to the target particle size (D50 ≤ 0.8 μm) respectively. High-energy ball milling is used for grinding and dispersion treatment, with a ball mill speed of 300 rpm, a ball-to-material ratio of 5:1, and the addition of 0.2% polyacrylic acid as a dispersant, and the ball milling time is 4 hours. All raw materials need to be sieved after grinding to ensure uniform particle size. For silicon carbide whiskers, first calcine at 800°C for 2 hours to remove surface impurities, then use silane coupling agent (KH550) for surface modification treatment to improve its dispersibility in the subsequent mixing process. The concentration of silane coupling agent is 2% (mass fraction), and the amount is 8% of the mass of silicon carbide whiskers.

[0138] 2. Mixing raw materials

[0139] The raw materials are mixed into two parts, the matrix layer mixture and the surface layer mixture. The matrix layer mixture is made by mixing zirconia, single crystal alumina, fused quartz powder, boron compound, rare earth oxide, silicon carbide whisker, nano-alumina and nano-zirconia according to the formula. During the mixing process, a 15% magnesium dihydrogen phosphate solution is added, with an amount of 10% of the total mass of the raw materials. The slurry is formed by wet ball milling for 6 hours. The slurry is dried at 80°C for 12 hours and then sieved through a 100 mesh sieve.

[0140] The surface layer mixture is made by adding 5% of nano-Y2Si2O7 powder to the matrix layer formula. During the mixing process, a 15% magnesium dihydrogen phosphate solution is added, with an amount of 10% of the total mass of the raw materials. The slurry is formed by wet ball milling for 6 hours. The slurry is dried at 80°C for 12 hours and then sieved through a 100 mesh sieve.

[0141] 3. Forming

[0142] The forming process uses layered filling and cold isostatic pressing technology. First, the matrix layer mixture is filled into the mold, with a thickness of 90% of the total thickness, and then the surface layer mixture is filled, with a thickness of 10% of the total thickness. After filling, cold isostatic pressing is used, with a pressure of 300 MPa and a holding time of 3 minutes to ensure the density and uniformity of the green body.

[0143] 4. Sintering

[0144] The sintering process includes three steps: pre-sintering, pressure sintering and hot isostatic pressing. First, the formed green body is pre-sintered at 800°C for 2 hours, with a heating rate of 3°C / min to remove the binder. Then, pressure sintering is carried out at 1650°C for 2 hours, with a nitrogen gas pressure of 10 MPa and a heating rate of 5°C / min. Finally, the sintered green body is subjected to hot isostatic pressing at 1500°C and 150 MPa in an argon gas environment for 1 hour, with a cooling rate of ≤5°C / min to further eliminate internal defects and improve material density. The atmosphere for pre-sintering and pressure sintering uses high-purity inert gas (nitrogen or argon) with an oxygen content of ≤10 ppm.

[0145] 5. Post-processing

[0146] The post-treatment includes two steps of molten salt impregnation and plasma spraying. Firstly, the sintered part is immersed in molten borosilicate glass at 1200℃ for 30 minutes to fill the surface pores. After the impregnation, the surface residual glass phase is removed by natural cooling. Subsequently, the plasma spraying technology is used to deposit a 40μm Al2O3-YAG composite coating on the surface, and the spraying parameters are as follows: current 500A, gas flow Ar / H2=45 / 15 SLPM, spraying distance 80mm, and spraying speed 200mm / s. A densified anti-permeation zirconia refractory part is prepared.

[0147] Comparative Example 1

[0148] Comparative Example 1 is compared with Example 3, and the base layer mixture and the surface layer mixture are not distinguished, but the same mixture is used for one-piece forming.

[0149] Basic powder raw materials and their amounts

[0150]

[0151]

[0152] 1. Raw material pretreatment

[0153] The raw material pretreatment includes grinding, sieving and surface treatment of silicon carbide whiskers. Firstly, the zirconia, single crystal alumina, fused quartz powder, boron compound and rare earth oxide are respectively ground to the target particle size (D50≤0.8μm). The high-energy ball mill is used for grinding and dispersing treatment, the ball mill speed is 300rpm, the ball-to-material ratio is 5:1, 0.2% polyacrylic acid is added as a dispersant, and the ball milling time is 4 hours. All the raw materials need to be sieved after grinding to ensure uniform particle size. For the silicon carbide whiskers, first calcined at 800℃ for 2 hours to remove surface impurities, and then surface modification treatment is carried out using silane coupling agent (KH550) to improve its dispersibility in the subsequent mixing process. The concentration of silane coupling agent is 5% (mass fraction), and the amount is 5% of the mass of silicon carbide whiskers.

[0154] 2. Mixing raw materials

[0155] The mixed raw materials are mixed by zirconia, single crystal alumina, fused quartz powder, boron compound, rare earth oxide, silicon carbide whiskers, nano-alumina and nano-zirconia according to the formula amount. During the mixing process, 15% magnesium dihydrogen phosphate solution is added, the amount of magnesium dihydrogen phosphate solution added is 20% of the total mass of raw materials, and wet ball milling is carried out for 6 hours to form a uniform slurry. After the slurry is dried at 80℃ for 12 hours, it is sieved through a 100 mesh sieve for use.

[0156] 3. Forming

[0157] The mixture was filled into the mold, and after filling was completed, cold isostatic pressing was performed at a pressure of 300 MPa for 3 minutes to ensure the density and uniformity of the blank.

[0158] 4. Sintering

[0159] The sintering process included three steps of pre-sintering, pressure sintering and hot isostatic pressing. First, the formed blank was pre-sintered at 800°C for 2 hours at a heating rate of 3°C / min to remove the binder. Subsequently, pressure sintering was performed at 1650°C for 2 hours with the introduction of 10 MPa of nitrogen at a heating rate of 5°C / min. Finally, the sintered blank was subjected to hot isostatic pressing at 1500°C under an argon atmosphere at 150 MPa for 1 hour at a cooling rate of ≤5°C / min to further eliminate internal defects and improve material density. High-purity inert gas (nitrogen or argon) was used for the atmosphere of pre-sintering and pressure sintering, with an oxygen content of ≤10 ppm.

[0160] 5. Post-processing

[0161] The post-processing included two steps of molten salt immersion and plasma spraying. First, the sintered piece was immersed in molten borosilicate glass at 1250°C for 30 minutes to fill the surface pores. After immersion, the surface residual glass phase was naturally cooled and removed. Subsequently, a 50 μm Al2O3-YAG composite coating was deposited on the surface using plasma spraying technology, with the spraying parameters being: current 500 A, gas flow Ar / H2 = 45 / 15 SLPM, spraying distance 80 mm, and spraying speed 200 mm / s. A densified and impermeable zirconia refractory piece was obtained.

[0162] Comparative Example 2

[0163] In Comparative Example 2, no rare earth oxide was added to the raw materials compared to Example 3.

[0164] Basic powder raw materials and their amounts

[0165]

[0166]

[0167] 1. Raw material pretreatment

[0168] Raw material pretreatment includes grinding, sieving and surface treatment of silicon carbide whiskers. First, zirconia, single crystal alumina, fused quartz powder, boron compounds are ground to the target particle size (D50≤0.8 μm) respectively. High-energy ball mill is used for grinding and dispersion treatment, the ball mill speed is 300 rpm, the ball-to-material ratio is 5:1, and 0.2% polyacrylic acid is added as a dispersant, the ball milling time is 4 hours. All raw materials need to be sieved after grinding to ensure uniform particle size. For silicon carbide whiskers, first calcined at 800°C for 2 hours to remove surface impurities, then surface modification treatment with silane coupling agent (KH550) to improve its dispersion in the subsequent mixing process. The concentration of silane coupling agent is 5% (mass fraction), and the amount is 5% of the mass of silicon carbide whiskers.

[0169] 2. Mixing raw materials

[0170] The preparation of mixed raw materials is divided into the preparation of matrix layer mixture and surface layer mixture. The matrix layer mixture is mixed by zirconia, single crystal alumina, fused quartz powder, boron compound, silicon carbide whisker, nano-alumina and nano-zirconia according to the formula amount. During the mixing process, 15% magnesium dihydrogen phosphate solution is added, the amount of magnesium dihydrogen phosphate solution added is 20% of the total mass of raw materials, wet ball milling for 6 hours to form a uniform slurry. After the slurry is dried at 80°C for 12 hours, it is sieved through a 100 mesh sieve for use.

[0171] The surface layer mixture is additionally added with 5% mass of nano-Y2Si2O7 powder based on the matrix layer formula. During the mixing process, 20% magnesium dihydrogen phosphate solution is added, the amount of magnesium dihydrogen phosphate solution added is 20% of the total mass of raw materials, wet ball milling for 6 hours to form a uniform slurry. After the slurry is dried at 80°C for 12 hours, it is sieved through a 100 mesh sieve for use.

[0172] 3. Forming

[0173] The forming process adopts layered filling and cold isostatic pressing forming technology. First, fill the matrix layer mixture in the mold, the thickness is 90% of the total thickness, then fill the surface layer mixture, the thickness is 10% of the total thickness. After filling, cold isostatic pressing is used, the pressure is 300 MPa, and the holding time is 3 minutes to ensure the density and uniformity of the green body.

[0174] 4. Sintering

[0175] The sintering process includes three steps: pre-sintering, gas pressure sintering, and hot isostatic pressing. First, the shaped body is pre-sintered at 800°C for 2 hours with a heating rate of 3°C / min to remove the binder. Subsequently, the gas pressure sintering is performed at 1650°C for 2 hours with a heating rate of 5°C / min under 10 MPa of nitrogen. Finally, the sintered body is subjected to hot isostatic pressing at 1500°C under 150 MPa of argon for 1 hour with a cooling rate of ≤5°C / min to further eliminate internal defects and improve material density. High-purity inert gas (nitrogen or argon) is used for the atmosphere of pre-sintering and gas pressure sintering, with an oxygen content of ≤10 ppm.

[0176] 5. Post-processing

[0177] The post-processing includes two steps: molten salt immersion and plasma spraying. First, the sintered piece is immersed in molten borosilicate glass at 1250°C for 30 minutes to fill the surface pores. After immersion, the surface residual glass phase is naturally cooled and removed. Subsequently, a 50 μm Al2O3-YAG composite coating is deposited on the surface using plasma spraying technology, with the following spraying parameters: current 500 A, gas flow Ar / H2 = 45 / 15 SLPM, spraying distance 80 mm, and spraying speed 200 mm / s. A densified and impermeable zirconia refractory piece is obtained.

[0178] Comparative Example 3

[0179] In Comparative Example 3, the molten salt immersion step in the post-processing process is omitted compared to Example 3.

[0180] Basic powder raw materials and their amounts

[0181]

[0182] 1. Raw material pretreatment

[0183] Raw material pretreatment includes grinding, sieving, and surface treatment of silicon carbide whiskers. First, the zirconia, single-crystal alumina, fused quartz powder, boron compound, and rare earth oxide are ground to the target particle size (D50 ≤ 0.8 μm) respectively. High-energy ball milling is used for grinding and dispersion treatment, with a ball mill speed of 300 rpm, a ball-to-material ratio of 5:1, and the addition of 0.2% polyacrylic acid as a dispersant, with a ball milling time of 4 hours. All raw materials need to be sieved after grinding to ensure uniform particle size. For silicon carbide whiskers, first calcine at 800°C for 2 hours to remove surface impurities, and then use silane coupling agent (KH550) for surface modification treatment to improve its dispersibility in the subsequent mixing process. The concentration of silane coupling agent is 5% (mass fraction), and the amount used is 5% of the mass of silicon carbide whiskers.

[0184] 2. Mixing raw materials

[0185] The raw materials are mixed into the matrix layer mixture and the surface layer mixture. The matrix layer mixture is mixed by zirconia, single crystal alumina, fused quartz powder, boron compound, rare earth oxide, silicon carbide whisker, nano-alumina and nano-zirconia according to the formula amount. During the mixing process, 15% magnesium dihydrogen phosphate solution is added, the amount of magnesium dihydrogen phosphate solution added is 20% of the total mass of the raw materials, wet ball milling is adopted for 6 hours to form a uniform slurry. The slurry is dried at 80°C for 12 hours and then sieved through a 100 mesh sieve for use.

[0186] The surface layer mixture is additionally added with 5% mass of nano Y2Si2O7 powder on the basis of the matrix layer formula, 20% magnesium dihydrogen phosphate solution is added during the mixing process, the amount of magnesium dihydrogen phosphate solution added is 20% of the total mass of the raw materials, wet ball milling is adopted for 6 hours to form a uniform slurry. The slurry is dried at 80°C for 12 hours and then sieved through a 100 mesh sieve for use.

[0187] 3. Forming

[0188] The forming process adopts layered filling and cold isostatic pressing forming technology. First, the matrix layer mixture is filled in the mold, the thickness is 90% of the total thickness, then the surface layer mixture is filled, the thickness is 10% of the total thickness. After filling, cold isostatic pressing is adopted, the pressure is 300 MPa, the pressure holding time is 3 minutes to ensure the density and uniformity of the blank.

[0189] 4. Sintering

[0190] The sintering process includes three steps of pre-sintering, gas pressure sintering and hot isostatic pressing. First, the formed blank is pre-sintered at 800°C for 2 hours, the heating rate is 3°C / min to remove the binder. Then, the gas pressure sintering is carried out at 1650°C for 2 hours, 10 MPa of nitrogen is introduced, the heating rate is 5°C / min. Finally, the sintered blank is treated by hot isostatic pressing at 1500°C, 150 MPa in argon environment for 1 hour, the cooling rate is controlled at ≤5°C / min to further eliminate internal defects and improve the material density. The atmosphere of pre-sintering and gas pressure sintering uses high-purity inert gas (nitrogen or argon), the oxygen content is ≤10 ppm.

[0191] 5. Post-processing

[0192] The post-processing is a plasma spraying step. An Al2O3-YAG composite coating with a thickness of 50 μm is deposited on the surface by plasma spraying technology, the spraying parameters are: current 500 A, gas flow Ar / H2=45 / 15 SLPM, spraying distance 80 mm, spraying speed 200 mm / s. A densified anti-permeation zirconia refractory is prepared.

[0193] Table 2 Performance test results

[0194]

[0195] Through the test of the embodiment, it can be seen (Table 2) that the zirconia refractory parts prepared by the present invention have a bulk density (≥5.76g / cm 3 ), apparent porosity (≤0.36%), flexural strength (≥535MPa) and resistance to glass penetration (erosion depth ≤0.2mm) all showed excellent performance. Among them, Example 3 has outstanding performance, with a bulk density of 5.95g / cm 3 , apparent porosity 0.28%, flexural strength 580Mpa, and erosion depth of 0.12mm against molten glass penetration. Combined with the test results of the comparative example, it can be seen that the excellent comprehensive performance is due to the combined effect of gradient structure, grain boundary control and surface defect repair.

[0196] Specifically, the Y2Si2O7 in the surface layer of the zirconia refractory prepared by the present invention forms a continuous Y-Si-O transition layer with the matrix ZrO2, so that the Y element content shows a gradient decreasing feature from the surface to the matrix. This gradient structure makes the thermal expansion coefficient decrease from about 5.8×10 -6 / ℃ slowly transition to the matrix of 10.5×10 -6 / ℃, the interfacial stress is significantly reduced. This gradient structure effectively inhibits the ZrO2 phase from transforming into a monoclinic phase, giving the material excellent flexural strength and anti-permeability properties. 3 + / Ce 4 + exists in the form of solid solution at the ZrO2 grain boundary, forming a (Y, Ce)-O-Si-Al composite glass phase. This high viscosity glass phase can effectively block Ca 2 The diffusion paths of corrosive ions such as Na+ and Na+ enable the material to exhibit minimal erosion depth in glass melt erosion tests. Example 3 achieved an erosion depth of 0.12 mm, a 71.4% reduction compared to Comparative Example 2 (0.42 mm), which did not incorporate rare earth elements. Furthermore, rare earth doping further enhances grain boundary bonding, contributing to improved bending resistance. Post-processing of the material through molten salt impregnation significantly reduces surface open porosity, with the B2O3-SiO2 glass phase filling defects larger than 1 μm through capillary action.

[0197] The above embodiments are exemplary and intended to illustrate the technical concepts and features of the present invention so that those skilled in the art can understand the present invention and implement it accordingly. They are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made in accordance with the spirit of the present invention are intended to be included within the scope of protection of the present invention.

Claims

1. A method for manufacturing a densified impermeable zirconia refractory component, characterized by: The basic powder raw materials including the following components and amounts are selected: 1000-1200 parts by mass of zirconium dioxide; 200-300 parts by mass of single crystal aluminum oxide; 100-200 parts by mass of fused silica powder; 40-100 parts by mass of a boron compound; 40-60 parts by mass of rare earth oxide; 20-40 parts by mass of silicon carbide whiskers; 60-100 parts by mass of nano-alumina; 20-40 parts by mass of nano zirconium oxide; 100-200 parts by mass of phosphate binder; Pretreatment of raw materials: Grinding zirconium dioxide, single crystal alumina, fused quartz powder, boron compound and rare earth oxide to predetermined particle sizes; calcining silicon carbide whiskers to remove surface impurities and then performing surface modification treatment with a silane coupling agent to improve dispersibility; Mix the ingredients: The matrix layer mixture is prepared by mixing zirconium dioxide, single crystal alumina, fused quartz powder, boron compound, rare earth oxide, silicon carbide whisker, nano alumina and nano zirconium oxide according to a formula; The surface layer mixture is based on the base layer formula, with 3-8% by mass of nano Y2Si2O7 powder added; Filling and molding the raw materials: Fill the mold with the base layer mixture to a thickness of 90-95% of the total thickness, and then fill it with the surface layer mixture to a thickness of 5-10% of the total thickness; after filling, cold isostatic pressing is performed; Sintering the formed green body: The formed green body is pre-sintered to remove the binder, and then gas pressure sintered under a protective atmosphere. The sintered green body is then hot isostatically pressed to further eliminate internal defects and improve material density. Post-processing of sintered parts: The sintered part is subjected to molten salt impregnation and plasma spraying treatment to produce a densified impermeable zirconia refractory part; During the post-processing of the sintered parts, the sintered parts are immersed in molten borosilicate glass at 1200-1250℃ for 25-40 minutes to fill the surface pores; after the immersion is completed, they are naturally cooled and the residual glass phase on the surface is removed; The phosphate binder is a magnesium dihydrogen phosphate solution. When preparing the base layer mixture, a magnesium dihydrogen phosphate solution with a concentration of 15-20% is added during the mixing process, and the amount of the magnesium dihydrogen phosphate solution added is 10-20% of the total mass of the raw materials. When preparing the surface layer mixture, a magnesium dihydrogen phosphate solution with a concentration of 15-20% is added during the mixing process, and the amount of the magnesium dihydrogen phosphate solution added is 10-20% of the total mass of the raw materials.

2. The method for manufacturing a densified impermeable zirconia refractory article according to claim 1, characterized in that: During the pretreatment of the raw materials, zirconium dioxide, single crystal alumina, fused quartz powder, boron compound and rare earth oxide are respectively ground to a particle size D50≤0.8μm, and 0.2% of the mass of the powder is added as a dispersant during the grinding process; during the surface modification treatment of the silicon carbide whiskers with a silane coupling agent, the concentration of the silane coupling agent used is 2-5%, and the amount used is 5-8% of the mass of the silicon carbide whiskers.

3. The method for manufacturing a densified impermeable zirconia refractory article according to claim 1, characterized in that: When preparing the surface layer mixture, the surface layer mixture is additionally added with 5% by mass of nano Y2Si2O7 powder on the basis of the base layer formula.

4. The method for manufacturing a densified impermeability-proof zirconia refractory article according to claim 1, characterized in that: During the raw material filling and molding process, the cold isostatic pressing pressure is 250-350 MPa and the holding time is 2-5 minutes.

5. The method for manufacturing a densified impermeability-proof zirconia refractory component according to claim 1, characterized in that: During the sintering process of the formed green body, the formed green body is pre-sintered at 780-820°C for 1-5 hours with a heating rate of 2-4°C / min to remove the binder; then, it is gas-pressed sintered at 1600-1700°C for 1-3 hours, with 8-12MPa nitrogen introduced and a heating rate of 4-6°C / min; the sintered green body is then hot isostatically pressed at 1400-1600°C and 120-180MPa argon environment for 0.8-1.5 hours, with a cooling rate controlled at ≤5°C / min to further eliminate internal defects and improve material density.

6. The method for manufacturing a densified impermeability-proof zirconia refractory article according to claim 5, characterized in that: The oxygen content in the atmosphere used for pre-sintering and gas pressure sintering is ≤10ppm.

7. The method for manufacturing a densified impermeability-proof zirconia refractory article according to claim 1, characterized in that: During the post-processing of the sintered parts, after molten salt impregnation, a 30-50μm Al2O3-YAG composite coating is deposited on the surface by plasma spraying.

8. A densified impermeable zirconia refractory component, characterized by: The refractory component is manufactured according to the manufacturing method according to any one of claims 1 to 7.

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