High-strength low-creep high-temperature-resistant cast ceramic filter sheet and manufacturing method thereof

Abstract

The application discloses a high-strength and low-creep high-temperature-resistant cast ceramic filter sheet and a manufacturing method thereof. The method comprises the following steps: mixing alpha-Al2O3, Longyan kaolin, zirconite, partially stabilized zirconium oxide, a binder, a surfactant and a dispersant to obtain a mixture; extruding, cooling and granulating the mixture to obtain ceramic feedstock; extruding, drawing and cooling the ceramic feedstock to obtain ceramic wire; using the ceramic wire as raw material, and using a ceramic 3D printer to process and form a green body; and performing degreasing and sintering on the green body in sequence to obtain the high-strength and low-creep high-temperature-resistant ceramic filter sheet. When zirconia-corundum-mullite composite ceramics are prepared, zirconite and partially stabilized zirconium oxide are added to improve the strength, creep resistance and high-temperature resistance; meanwhile, a ceramic 3D fused deposition forming printing technology is adopted and a sintering process is optimized to avoid cracking, and the filtering efficiency is improved in the casting process.

Description

Technical Field

[0001] This invention relates to the field of preparation technology of novel cast ceramic filter materials, specifically to a high-strength, low-creep, high-temperature resistant cast ceramic filter and its manufacturing method. Background Technology

[0002] Casting is not only an indispensable and crucial link in the development of modern machinery manufacturing industry, but also a vital support for the development of many major technical equipment. With the increase in casting output and the rising quality requirements for casting products, new filtration technologies are constantly emerging. Cast ceramic filter sheets, as a key material in casting filtration, are prone to breakage and pore blockage due to harsh working environments, resulting in significant wear and tear, poor filtration efficiency, and ultimately, increased costs. Therefore, cast ceramic filter sheets should possess properties such as high strength, low high-temperature plastic deformation, and high-temperature resistance.

[0003] Currently, the main products on the market are straight-pore honeycomb ceramics or foam ceramics prepared from raw materials such as silicon carbide, alumina, and zirconium oxide using extrusion molding or organic foaming processes, which are used as cast ceramic filter sheets. For example, Chinese invention patent CN113307629A discloses a silicon carbide foam ceramic and its preparation method. This patent uses silicon carbide powder and alumina powder as raw materials, polyurethane foam as a template, and fires it at 1500℃ to prepare silicon carbide foam ceramic with a bulk density of 0.998 g / cm³. 3 With a porosity ≥79% and a maximum compressive strength of only 2.09 MPa, it can be used as a cast ceramic filter; however, its low firing temperature results in poor performance in high-temperature working environments such as cast iron and cast steel. Chinese invention patent CN103787688A discloses a method for preparing zirconia foam ceramics. This patent uses zirconia ceramic powder as the matrix material, adding polyether or polyester polyol, catalyst, surfactant, and foaming agent. After curing, pores are opened, and then sintered at 1700℃ to prepare cast foam ceramic filter sheets. Due to their low strength, these foam ceramics are prone to breakage in actual use due to the high flow rate and impact force of molten metal. The broken filter fragments falling into the molten metal can affect the quality of metal castings. Chinese invention patent CN1138608961A discloses a high-temperature precision casting method for low-creep corundum mullite, which produces a corundum-mullite-based filter sheet using industrial alumina and high-purity silica as raw materials, with the addition of Re rare earth oxides. The filter sheet has a load softening temperature greater than 1700℃. However, the invention uses high-purity raw materials and adds expensive Re rare earth oxides, resulting in excessively high production costs, making it unsuitable for practical application. Summary of the Invention

[0004] The purpose of this invention is to overcome the above-mentioned technical deficiencies and propose a high-strength, low-creep, high-temperature resistant cast ceramic filter and its manufacturing method, thereby solving the technical problems of low strength, poor high-temperature creep performance, and poor high-temperature resistance of filter sheets in the prior art.

[0005] In a first aspect, the present invention provides a method for manufacturing a high-strength, low-creep, high-temperature resistant cast ceramic filter, comprising the following steps:

[0006] The ceramic matrix components, additives, binders, surfactants, and dispersants are mixed and then subjected to a first kneading process to obtain a mixture. The ceramic matrix components include α-Al2O3 and Longyan kaolin. The additives include zircon and partially stabilized zirconium oxide.

[0007] The mixture is extruded, cooled, and granulated to obtain ceramic feedstock;

[0008] Ceramic feedstock is extruded, drawn, and cooled to obtain ceramic wire.

[0009] Using ceramic wire as raw material, ceramic 3D printer is used to process and shape it to obtain high-temperature cast ceramic filter blanks;

[0010] Degreasing is performed on the high-temperature cast ceramic filter blank to obtain a high-temperature cast ceramic filter blank with a special pore structure.

[0011] High-temperature cast ceramic filter blanks with special pore structures are fired to obtain high-strength, low-creep high-temperature ceramic filter blanks.

[0012] In a second aspect, the present invention provides a high-strength, low-creep, high-temperature resistant cast ceramic filter, which is obtained by the manufacturing method of the high-strength, low-creep, high-temperature resistant cast ceramic filter provided in the first aspect of the present invention.

[0013] Compared with the prior art, the beneficial effects of the present invention include:

[0014] This invention uses α-Al2O3 and Longyan kaolin as the main raw materials to prepare zirconia-corundum-mullite multiphase ceramics, and adds zircon and some stabilized zirconia to improve its strength, creep resistance and high temperature resistance. At the same time, ceramic 3D fused deposition modeling technology and optimized sintering process are used to avoid cracking, which can improve filtration efficiency during casting. Attached Figure Description

[0015] Figure 1 This is a SEM image of Longyan kaolin, the raw material used in this invention;

[0016] Figure 2These are comparative photographs of commercially available zirconia foam filter sheets and the high-strength, low-creep, high-temperature resistant cast ceramic filter sheet of Example 1 of this invention.

[0017] Figure 3 This is a SEM image of the high-strength, low-creep, high-temperature resistant cast ceramic filter sheet in Embodiment 1 of the present invention;

[0018] Figure 4 This is the XRD pattern of the high-strength, low-creep, high-temperature resistant cast ceramic filter sheet in Embodiment 1 of the present invention. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0020] Corundum possesses characteristics such as high elasticity, wear resistance, high temperature resistance, corrosion resistance, and oxidation resistance, while mullite exhibits characteristics such as uniform expansion, high load softening point, good thermal shock stability, small high-temperature plastic deformation value, high hardness, and good chemical corrosion resistance. Zirconia-toughened corundum-mullite multiphase ceramics are high-temperature resistant multiphase ceramic materials prepared by introducing zirconia as a stabilizer into corundum and mullite as the main crystalline phases. Their comprehensive performance is superior to that of pure alumina ceramics and mullite ceramics.

[0021] Zircon has a high melting point and can exist stably at high temperatures, but its sintering is very slow because it can only rely on solid-state diffusion at high temperatures. This invention utilizes a scientifically proportioned raw material formula and adds suitable sintering aids to achieve its excellent high-temperature performance. Simultaneously, zircon has high hardness and brittleness, making its molding process relatively difficult, especially when creating complex shapes or detailed parts, often leading to cracking. This invention further avoids these problems by employing 3D printing technology and optimizing the sintering process.

[0022] Based on this, the present invention is proposed.

[0023] In a first aspect, the present invention provides a method for manufacturing a high-strength, low-creep, high-temperature resistant cast ceramic filter, comprising the following steps:

[0024] S1. The ceramic matrix components, additives, binders, surfactants, and dispersants are mixed and then subjected to a first kneading process to obtain a mixture; wherein, the ceramic matrix components include: α-Al2O3 and Longyan kaolin; the additives include: zircon and partially stabilized zirconium oxide;

[0025] S2. The mixture is extruded, cooled, and granulated to obtain ceramic feedstock;

[0026] S3. The ceramic feedstock is extruded, drawn, and cooled to obtain ceramic wire.

[0027] S4. Using ceramic wire as raw material, ceramic 3D printer is used to process and shape it to obtain high-temperature cast ceramic filter blanks;

[0028] S5. Degrease the high-temperature cast ceramic filter blank to obtain a high-temperature cast ceramic filter blank with a special pore structure.

[0029] S6. The high-temperature cast ceramic filter blank with a special pore structure is fired to obtain a high-strength, low-creep high-temperature ceramic filter.

[0030] This invention uses α-Al₂O₃ and Longyan kaolin as the main raw materials to prepare a zirconium oxide-corundum-mullite multiphase ceramic, and adds zircon and some stabilized zirconium oxide to improve its strength and creep resistance. Among these, Longyan kaolin serves as the main "silicon source," and compared to other kaolins, its unique lamellar structure (such as...) Figure 1 This process improves the high-temperature ceramic filter's resistance to high temperatures, ensuring structural stability under high-temperature conditions. It also enhances its plasticity and adjustability, making it more suitable for molding and processing, thus saving costs to some extent. Simultaneously, the synthesis of mullite from Longyan kaolin and corundum at high temperatures produces corundum-mullite multiphase ceramics. This retains the high strength of corundum while generating a certain amount of high-viscosity liquid phase, resulting in cast ceramic filter sheets with excellent thermal shock resistance and high-temperature resistance to plastic deformation. Furthermore, the use of ceramic 3D fused deposition modeling (FDM) technology and optimized sintering processes prevent cracking and improve filtration efficiency during casting.

[0031] In this embodiment, the ceramic matrix components and additives need to be dried, ground, pulverized, and sieved before use.

[0032] In this embodiment, the ceramic matrix composition, by weight percentage, includes: 66%–94% α-Al₂O₃ and 6%–34% Longyan kaolin.

[0033] In this embodiment, the amount of zircon is 5% to 15% of the ceramic matrix composition, and more specifically 10%; the amount of partially stabilized zirconium oxide is 10% to 30% of the ceramic matrix composition.

[0034] In some specific embodiments of the present invention, the chemical composition of α-Al2O3 includes: aluminum oxide content ≥98%, other impurities not exceeding 2%, and passing through a 325-mesh sieve; the chemical composition of Longyan kaolin includes: aluminum oxide 35%–45%, silicon dioxide 50%–60%, other impurities not exceeding 5%, and passing through a 325-mesh sieve; the chemical composition of zircon includes: silicon dioxide 30%–40%, zirconium oxide 60%–70%, and other impurities not exceeding 2%; the chemical composition of partially stabilized zirconium oxide includes: zirconium oxide 93%–96%, yttrium oxide 4%–7%, and other impurities not exceeding 1%.

[0035] In this embodiment, the adhesive comprises, by weight percentage: 40% to 60% of a mixture of paraffin wax and polylactic acid in any proportion, and 40% to 60% of a mixture of polyethylene wax and EVA hot melt adhesive in any proportion.

[0036] In some specific embodiments of the present invention, the adhesive is obtained by second mixing of the raw materials of the adhesive; wherein the temperature of the second mixing is 160-180°C and the time of the second mixing is 2-4 hours.

[0037] In this embodiment, the amount of binder added is 5% to 10% of the total mass of the ceramic matrix components and additives.

[0038] In this embodiment, the surfactant is stearic acid, added at 1% to 3% of the total mass of the ceramic matrix component and the additives; the dispersant is palmitic acid, added at 2% to 4% of the total mass of the ceramic matrix component and the additives. In this invention, the main function of stearic acid is to reduce surface tension through its excellent surface activity; the main function of palmitic acid is to improve dispersion stability by forming an adsorption layer. This invention improves the wetting properties and flowability of the material by adding surfactants and dispersants, while maintaining the dispersed state of the particles, thereby improving the printing effect and quality.

[0039] In this embodiment, the wire diameter is 0.6–1.4 mm.

[0040] In this embodiment, the porosity of the high-temperature cast ceramic filter green body is 85% to 90%, the pore wall thickness is 0.4 to 0.6 mm, and the pore size is 0.5 to 0.7 mm.

[0041] In this embodiment, the degreasing process employs a two-step degreasing method: first, solvent degreasing, followed by drying and then thermal degreasing. During solvent degreasing, a mixture of butanone and ethanol in any proportion is used as the solvent; the soaking temperature is 120–200°C, and the soaking time is 12–24 hours; the drying temperature is 80–120°C, and the drying time is 6–24 hours. During thermal degreasing, the temperature is increased from room temperature to 600°C at a rate of 0.25–0.5°C / min, and then held at 300°C, 350°C, 400°C, and 450°C for 0.5–2 hours respectively.

[0042] In this embodiment, the firing conditions are as follows: the heating rate is 5-8℃ / min, the maximum firing temperature is 1620-1700℃, and the maximum temperature holding time is 1-3h.

[0043] In a second aspect, the present invention provides a high-strength, low-creep, high-temperature resistant cast ceramic filter, which is obtained by the manufacturing method of the high-strength, low-creep, high-temperature resistant cast ceramic filter provided in the first aspect of the present invention.

[0044] To avoid redundancy, some of the raw materials used in the following embodiments and comparative examples of this invention are summarized as follows:

[0045] The chemical composition of α-Al2O3 from the mountain aluminum plant includes: aluminum oxide content of 99.60%, passing through a 325-mesh sieve;

[0046] The chemical composition of Longyan kaolin includes: 41.63% alumina, 55.09% silicon dioxide, and passes through a 325-mesh sieve;

[0047] The chemical composition of zircon includes: 32.91% silicon dioxide and 65.44% zirconium oxide;

[0048] The chemical composition of partially stabilized zirconium oxide includes: 94.78% zirconium oxide and 5.20% yttrium oxide.

[0049] Example 1

[0050] A method for manufacturing a high-strength, low-creep, high-temperature resistant cast ceramic filter sheet, comprising the following specific steps:

[0051] (1) The α-Al2O3 of the mountain alumina, the kaolin of Longyan, the zircon and the partially stabilized zircon oxide were dried, ground and pulverized and sieved to obtain ceramic powder; wherein, the mass ratio of the α-Al2O3 of the mountain alumina to the kaolin of Longyan was 87.47:12.53; the amount of zircon added was 10 wt%; and the amount of the partially stabilized zircon oxide added was 10 wt%.

[0052] (2) The raw materials of the binder are added to the mixer in a certain proportion and mixed to obtain a premixed liquid; wherein, the main component of the binder is a mixture of 60% paraffin wax and polylactic acid (the mass ratio of paraffin wax and polylactic acid is 2:3), and the auxiliary material is a mixture of 40% polyethylene wax and EVA hot melt adhesive (the mass ratio of polyethylene wax and EVA hot melt adhesive is 1:1); the mixing temperature is 180℃ and the mixing time is 4h.

[0053] (3) Add the ceramic powder obtained in step (1) to the above premixed liquid (accounting for 7% of ceramic powder), and add 3% of the surfactant and 3% of the dispersant to the ceramic powder, and continue to knead to obtain a mixture; wherein, the surfactant is stearic acid and the dispersant is palmitic acid; the kneading temperature is 180℃ and the kneading time is 4h.

[0054] (4) The mixture obtained in step (3) is extruded, cooled, and granulated to obtain ceramic feed;

[0055] (5) Wire drawing: The ceramic feed obtained in step (4) is put into a single screw extruder for extrusion, wire drawing and cooling to obtain ceramic wire for 3D printing; wherein the wire diameter is 0.8mm.

[0056] (6) Ceramic 3D printing: Using the ceramic wire obtained in step (5) as raw material, the ceramic 3D printer is used to process and shape it to obtain a high-temperature cast ceramic filter blank; wherein the porosity is 85%, the pore wall thickness is 0.5mm, and the pore size is 0.6mm.

[0057] (7) Degreasing: The high-temperature cast ceramic filter green body obtained in step (6) is degreased to obtain a high-temperature cast ceramic filter green body with a special pore structure. The degreasing process adopts a two-step degreasing: firstly, solvent degreasing is carried out, and the solvent is a mixture of butanone and ethanol with a mass ratio of 3:7. The mixture is soaked in a temperature range of 160℃ for 24 hours. After the solvent degreasing is completed, the ceramic green body is taken out and dried at 100℃ for 12 hours. Then, thermal degreasing is carried out, and the temperature is raised from room temperature to 600℃ at a heating rate of 0.5℃ / min. The temperature is then held at 300℃, 350℃, 400℃ and 450℃ for 1 hour respectively.

[0058] (8) Firing: The high-temperature cast ceramic filter blank with special pore structure obtained by degreasing in step (7) is placed in a high-temperature box-type resistance furnace for firing. The heating rate is 5℃ / min, the maximum firing temperature is 1670℃, and the maximum temperature is held for 2h to obtain a high-strength, low-creep high-temperature ceramic filter.

[0059] Testing showed that the high-strength, low-creep high-temperature ceramic filter prepared in Example 1 of this invention had a compressive strength of 17.2 MPa. The high-temperature pyroplastic index (PI) of the sample (100 mm × 15 mm × 5 mm) was measured to be 4.21 × 10⁻⁶ after being heated at 1650 °C for 2 hours using the two-point support method. -6 mm -1 (Typically, the PI of ceramic materials is no greater than 6×10) -6 mm -1 It exhibits excellent creep resistance, a softening temperature under load of 1650℃, and shows no cracking after 30 thermal shocks (1100℃ to room temperature, air-cooled), with a strength loss rate of 6.15%; furthermore, its bulk density is 0.63 g / cm³. 3 With a porosity of 85%, the cast ceramic filter can be used in high-temperature casting environments such as cast iron and cast steel.

[0060] Please see Figure 2 ,pass Figure 2 As can be seen, compared with commercially available zirconia foam filter sheets, the high-temperature resistant cast ceramic filter sheet prepared by the present invention using 3D printing technology has a more uniform structure and thus has higher strength.

[0061] Please see Figure 3 ,pass Figure 3 It can be seen that mullite and zirconia grains are uniformly dispersed between and within the alumina crystals, effectively inhibiting the abnormal growth of corundum crystals. In addition, the presence of a small number of pores in the sample can serve as a "buffer zone" for thermal shock to prevent crack propagation, thus giving the high-temperature cast filter excellent mechanical properties and thermal shock resistance.

[0062] Please see Figure 4 ,pass Figure 4 It can be seen that the main crystalline phases of the high-temperature cast filter are corundum, mullite, monoclinic zirconia (t-ZrO2) and tetragonal zirconia (m-ZrO2). The simultaneous presence of t-ZrO2 and m-ZrO2 proves that ZrO2 causes stress-induced phase transformation toughening and martensitic phase transformation, resulting in a volume effect that causes more microcracks in the sample. Microcracks can absorb part of the fracture energy and improve the mechanical properties of the material.

[0063] Comparative Examples 1-3

[0064] The only difference between Comparative Examples 1-3 and Example 1 is that the mass ratio of α-Al2O3 to Longyan kaolin is different, and no additives are added, as shown in Table 1.

[0065] Examples 2-4 and Comparative Example 4

[0066] The only difference between Examples 2-4 and Comparative Example 4 and Example 1 is the amount of zircon and partially stabilized zirconium oxide doped. Since stabilized zirconium oxide contains a small amount of Y₂O₃, it reacts with free SiO₂ at high temperatures to form a liquid phase that promotes sintering. Therefore, as the additive content increases, the firing temperature decreases. See Table 1 for details.

[0067] experimental group

[0068] Performance tests were conducted on Examples 2-5 and Comparative Examples 1-2, and the results are shown in Table 1.

[0069] Table 1

[0070]

[0071] Testing revealed that the high-strength, low-creep high-temperature ceramic filter prepared according to the embodiments of the present invention exhibits a compressive strength of 16.7–18.2 MPa. The high-temperature pyroplastic index (PI) of the sample (100 mm × 15 mm × 5 mm) measured using the two-point support method after holding at 1650 °C for 2 hours was less than 6 × 10⁻⁶. -6 mm -1 This indicates that it has excellent creep resistance, a softening temperature under load greater than 1600℃, and no cracking after 30 thermal shocks (1100℃ to room temperature, air cooling), with a strength loss rate of no more than 15%; in addition, its bulk density is 0.61~0.63g / cm³. 3 With a porosity of 82-90%, it can ensure that cast ceramic filter sheets can be used in high-temperature casting environments such as cast iron and cast steel.

[0072] As can be seen from Comparative Examples 1-3, with the increase of Longyan kaolin, the content of mullite increases accordingly, and the alkali metal ions such as K and Na in the raw materials also increase. At high temperatures, they easily react with free SiO2 to form a glassy phase, which leads to a decrease in firing temperature, a decrease in load softening temperature, and a decrease in strength. However, the intergrowth of short columnar mullite and corundum and the appropriate high viscosity glassy phase can effectively inhibit crystal slip at high temperatures, thereby improving the creep resistance of high-temperature cast filter sheets.

[0073] As can be seen from Comparative Examples 2, 4 and Example 2, the introduction of zircon can significantly improve the compressive strength and load softening temperature of ceramic filter sheets, and the best performance is achieved when the zircon content is 10%.

[0074] As can be seen from Examples 1, 3, and 4, with the increase of the partially stabilized zirconium oxide content, the introduced Y2O3 acts as a sintering aid, which reduces the firing temperature, gradually increases the compressive strength and high-temperature plastic deformation index of the ceramic filter, and gradually decreases the load softening temperature.

[0075] In summary, compared with the prior art, the beneficial effects of the present invention are as follows:

[0076] (1) The high-temperature cast ceramic filter of the present invention has high compressive strength. The high-temperature cast ceramic filter prepared by the present invention has a compressive strength of 16.7-18.2 MPa. This is because the present invention is carefully designed in terms of phase composition. Using raw materials such as alumina, kaolin, and zircon, a corundum is formed as the main crystalline phase, and mullite and zirconium oxide are as secondary crystalline phases. Moreover, the mullite and zirconium oxide grains are uniformly dispersed in the intergranular and intragranular spaces of alumina, so that the fracture mode is mainly transgranular fracture and the microstructure is uniform. Therefore, the high-temperature cast filter has high strength. In addition, the high-temperature cast filter of the present invention has higher strength than other high-temperature cast filters made of silicon carbide and other raw materials. It is not easy to break at high temperature and has a better filtration effect.

[0077] (2) The high-temperature cast ceramic filter sheet of the present invention exhibits good creep resistance. The high-temperature plasticity index of the high-temperature cast ceramic filter sheet prepared by the present invention is less than 6×10⁻⁶. -6 mm -1 The high-temperature cast ceramic filter prepared by this invention exhibits excellent creep resistance because it contains a large number of crystalline phases, which relatively reduces the volume fraction of the glass phase and increases the density of the high-temperature cast ceramic filter. When working in a high-temperature environment, its crystal structure is less likely to become loose. Therefore, the high-temperature creep resistance of this invention is good, enabling the high-temperature cast ceramic filter to work stably at high temperatures, casting precision high-grade refractory materials, and improving the casting qualification rate of precision castings.

[0078] (3) The high-temperature cast ceramic filter of the present invention has good high-temperature resistance. The high-temperature cast ceramic filter prepared by the present invention has a load softening temperature of 1670℃. This is because the added zircon can decompose into zirconium oxide and silicon dioxide at high temperature. The decomposed silicon dioxide reacts with alumina in the high-temperature environment to generate secondary mullite. The corundum, mullite and zirconium oxide three phases grow interlaced and are evenly distributed, which effectively reduces the volume fraction of the glass phase. Moreover, the newly generated zirconium oxide is also an excellent refractory material. Therefore, it can improve the refractoriness of the high-temperature cast ceramic filter, so that it can work stably in a high-temperature environment above 1600℃, meet most metal casting conditions, and will not break or soften during use, thus improving the quality of metal castings.

[0079] (4) The present invention uses ceramic 3D printing FDM process to prepare filter sheets with high strength and toughness. Its high molding precision can effectively avoid pore blockage, thus preparing high temperature cast ceramic filter sheets with controllable pore size and shape and excellent filtration effect, overcoming the shortcomings of other types of cast ceramic filter sheets that are prone to defects and poor filtration effect during use.

[0080] (5) The cost of the high-temperature cast ceramic filter of the present invention is 10% to 15% lower than that of the commonly used precision ceramic filter for cast steel. This is because the present invention contains inexpensive Longyan kaolin and zircon as silicon and zircon sources in all raw materials. Through careful design of the formula, the high-temperature cast filter has excellent performance and meets the requirements of use.

[0081] The specific embodiments of the present invention described above do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made in accordance with the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A method for manufacturing a high-strength, low-creep, high-temperature resistant cast ceramic filter, characterized in that, Includes the following steps: The ceramic matrix components, additives, binders, surfactants, and dispersants are mixed and then subjected to a first kneading process to obtain a mixture. The mixture is extruded, cooled, and granulated to obtain ceramic feedstock; The ceramic feedstock is extruded, drawn, and cooled to obtain ceramic wire. Using the ceramic wire as raw material, a high-temperature cast ceramic filter blank is obtained by processing it with a ceramic 3D printer. The high-temperature cast ceramic filter blank is degreased to obtain a high-temperature cast ceramic filter blank with a special pore structure. High-temperature cast ceramic filter blanks with special porous structures are fired to obtain high-strength, low-creep high-temperature ceramic filter sheets; among which, The ceramic matrix composition, by weight percentage, comprises: α-Al₂O₃ 66%~94% and Longyan kaolin 6%~34%; The additives include zircon and partially stabilized zirconium oxide; the amount of zircon is 10% of the ceramic matrix composition, and the amount of partially stabilized zirconium oxide is 10% to 30% of the ceramic matrix composition. The porosity of the high-temperature cast ceramic filter green body is 85%~90%, the pore wall thickness is 0.4~0.6mm, and the pore size is 0.5~0.7mm; The firing conditions are as follows: heating rate of 5~8℃ / min, maximum firing temperature of 1620~1700℃, and maximum holding time of 1~3h.

2. The method for manufacturing the high-strength, low-creep, high-temperature resistant cast ceramic filter according to claim 1, characterized in that, The chemical composition of the α-Al2O3 includes: aluminum oxide content ≥98%, other impurities not exceeding 2%, and passing through a 325-mesh sieve; the chemical composition of the Longyan kaolin includes: aluminum oxide 35%~45%, silicon dioxide 50%~60%, other impurities not exceeding 5%, and passing through a 325-mesh sieve; the chemical composition of the zircon includes: silicon dioxide 30%~40%, zirconium oxide 60%~70%, and other impurities not exceeding 2%; the chemical composition of the partially stabilized zirconium oxide includes: zirconium oxide 93%~96%, yttrium oxide 4%~7%, and other impurities not exceeding 1%.

3. The method for manufacturing the high-strength, low-creep, high-temperature resistant cast ceramic filter according to claim 1, characterized in that, The adhesive comprises, by weight percentage: 40% to 60% of a mixture of paraffin wax and polylactic acid in any proportion, and 40% to 60% of a mixture of polyethylene wax and EVA hot melt adhesive in any proportion; the adhesive is obtained by a second mixing of the raw materials of the adhesive; wherein the temperature of the second mixing is 160 to 180°C, and the time of the second mixing is 2 to 4 hours.

4. The method for manufacturing the high-strength, low-creep, high-temperature resistant cast ceramic filter according to claim 1, characterized in that, The amount of the binder added is 5% to 10% of the total mass of the ceramic matrix component and the additive; the surfactant is stearic acid, and the amount added is 1% to 3% of the total mass of the ceramic matrix component and the additive; the dispersant is palmitic acid, and the amount added is 2% to 4% of the total mass of the ceramic matrix component and the additive.

5. The method for manufacturing the high-strength, low-creep, high-temperature resistant cast ceramic filter according to claim 1, characterized in that, The wire diameter is 0.6~1.4mm.

6. The method for manufacturing the high-strength, low-creep, high-temperature resistant cast ceramic filter according to claim 1, characterized in that, The degreasing process employs a two-step degreasing method: first, solvent degreasing, followed by drying and then thermal degreasing. In the solvent degreasing process, a mixture of butanone and ethanol in any proportion is used as the solvent, and the soaking temperature is 120–200 °C for 12–24 h. The drying temperature is 80–120 °C for 6–24 h. In the thermal degreasing process, the temperature is increased from room temperature to 600 °C at a rate of 0.25–0.5 °C / min, and then held at 300 °C, 350 °C, 400 °C, and 450 °C for 0.5–2 h respectively.

7. A high-strength, low-creep, high-temperature resistant cast ceramic filter, characterized in that, The high-strength, low-creep, high-temperature resistant cast ceramic filter is obtained by the manufacturing method of the high-strength, low-creep, high-temperature resistant cast ceramic filter as described in any one of claims 1 to 6.

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