A preparation method and application of a 3D printed silicon-based ceramic core

Abstract

The present invention provides a method for preparing a 3D printed silicon-based ceramic core, and the method is as follows: After mixing 1,6-ethylene glycol diacrylate, epoxy acrylate, trimethylolpropane triacrylate and polyurethane acrylate, add 2,4,6-trimethylbenzoyl-ethoxy-phenyl phosphine oxide, oleic acid and dispersant BYK-111, and stir and mix to obtain a premixed liquid; After mixing fused quartz powder, white fused alumina and zirconium silicate, add metallic Si powder to obtain a mixture; Add the premixed liquid to the mixture, ball mill to obtain a ceramic slurry, prepare a ceramic core blank by 3D printing, clean, dry, and then calcine to obtain a 3D printed silicon-based ceramic core. It also provides an application for manufacturing hollow blades. The 3D printed silicon-based ceramic core prepared by the present invention has excellent mechanical properties and can be used for manufacturing hollow blades.

Description

Technical Field

[0001] The present invention belongs to the technical field of aerospace materials, and particularly relates to a preparation method and application of a 3D printed silicon-based ceramic core. Background Art

[0002] With the rapid development of the aerospace industry and the increase in the thrust-to-weight ratio of aero-engines, the turbine gas temperature of the engine has been continuously rising. Improving the temperature-bearing capacity of materials can significantly increase the turbine gas temperature. However, so far, the operating temperature of superalloys has approached the melting temperature. Therefore, cooling technologies are widely applied to all investment-cast advanced hollow turbine blades to withstand higher gas temperatures, which has led to increasingly complex internal cooling channels in turbine blades. Ceramic cores are used to form the internal cooling structure and provide precise and complex internal cavities in the investment casting of turbine blades, and are indispensable adapters for preparing the internal cavity structure of blades. Therefore, the core needs to meet the following conditions: (1) High refractoriness to ensure no softening and deformation during pouring and the solidification process of the casting. (2) Low thermal expansion rate to ensure the stability of the internal cavity size of the casting. (3) Good chemical stability to ensure the surface accuracy of the core. (4) High strength to withstand the impact and extrusion of the wax liquid without fracture and damage. (5) Easy to remove. The ceramic core must have sufficient porosity so that the ceramic core can be removed from the casting.

[0003] Several traditional manufacturing methods can be used to manufacture ceramic cores, such as injection molding method, hot pressing method, and gel casting method, etc. However, due to the long mold manufacturing cycle and low productivity, traditional ceramic cores have the disadvantages of long production time and high cost. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a preparation method and application of a 3D printed silicon-based ceramic core in view of the deficiencies of the above-mentioned prior art. The 3D printed silicon-based ceramic core has excellent mechanical properties and can be used for the manufacture of hollow blades.

[0005] To solve the above technical problem, the technical solution adopted by the present invention is: A preparation method of a 3D printed silicon-based ceramic core, and the method is as follows:

[0006] S1. Preparation of the premixed solution: After mixing 1,6-ethylene glycol diacrylate, epoxy acrylate, trimethylolpropane triacrylate, and polyurethane acrylate, add 2,4,6-trimethylbenzoyl-ethoxy-phenylphosphine oxide, oleic acid, and dispersant BYK-111, and stir and mix to obtain the premixed solution;

[0007] S2. Mix the coarse and fine fused silica powders in a mass ratio of 8:2 to obtain the mixed fused silica powder. Then, mix the mixed fused silica powder with white fused alumina and zirconium silicate in a mass ratio of 17:2:1. Next, add metallic Si powder, and mix and stir evenly to obtain a mixture. The amount of metallic Si powder is 0.4% of the mass of the mixed fused silica powder. The average particle size of the coarse fused silica powder is 22.1 μm, and the average particle size of the fine powder is 4.89 μm.

[0008] S3. Add the premixed liquid obtained in S1 to the mixture obtained in S2, and ball-mill at a speed of 1200 rpm / min for 30 min to obtain a ceramic slurry.

[0009] S4. Add the ceramic slurry obtained in S3 to a 3D printer to prepare a ceramic core blank. The exposure power of the 3D printer is 23 mW / cm 2 , the exposure time is 6 s, and the slice thickness is 100 μm.

[0010] S5. After the ceramic core blank obtained in S4 is cleaned and dried by an ultrasonic machine, heat the ceramic core blank from room temperature to 200 °C at a heating rate of 1 °C / min, then heat it to 204 °C at a heating rate of 1 °C / min, hold for 1 h, then heat it to 378 °C at a heating rate of 1 °C / min, hold for 1 h, then heat it to 488 °C at a heating rate of 1 °C / min, hold for 1 h, then heat it to 600 °C at a heating rate of 2 °C / min, hold for 1 h, and then heat it to 1200 °C at a heating rate of 2 °C / min, hold for 6 h, and naturally cool to room temperature to obtain a 3D printed silicon-based ceramic core.

[0011] Preferably, the premixed liquid in S1 is composed of the following raw materials by volume fraction: 25% of 1,6-ethylene glycol diacrylate, 14% of epoxy acrylate, 24% of trimethylolpropane triacrylate, 28% of polyurethane acrylate, 3% of 2,4,6-trimethylbenzoyl-ethoxy-phenylphosphine oxide, 2% of oleic acid, and the balance is dispersant BYK-111.

[0012] Preferably, the solid content of the ceramic slurry in S3 is 56 vol%.

[0013] Preferably, the shrinkage rate of the 3D printed silicon-based ceramic core in the three-dimensional direction in S5 is 4.38% - 5.47%, and the interlayer strength and in-layer strength at room temperature are 11.35 MPa and 17.21 MPa, respectively.

[0014] The present invention also provides the application of the 3D printed silicon-based ceramic core prepared by the above preparation method. The 3D printed silicon-based ceramic core is used for manufacturing hollow blades.

[0015] The present invention has the following advantages compared with the prior art:

[0016] The present invention uses stereolithography technology to prepare a silicon-based ceramic core containing metal Si powder, that is, a 3D-printed silicon-based ceramic core. Under the combined action of the oxidation reaction of metal Si and its low melting point, when the content of metal Si powder is 0.4 wt%, the performance of the ceramic core reaches the best. The shrinkage rates in three-dimensional directions are 5.47%, 4.38%, and 5.09% respectively. The bulk density and porosity of the ceramic core are 1.68 g / cm 3 and 28.07% respectively. The interlayer strength and in-layer strength at room temperature reach 11.35 MPa and 17.21 MPa respectively, and the high-temperature bending strengths are 8.014 MPa and 10.771 MPa. Therefore, the optimal addition of metal Si powder can provide a silicon-based ceramic core with excellent mechanical properties, thus promoting the application and development of silicon-based ceramic cores in the manufacture of hollow blades.

[0017] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Description of the Drawings

[0018] Figure 1 shows the relationship between the shrinkage rates in different directions of the ceramic core in Example 1 of the present invention and the content of metal silicon powder.

[0019] Figure 2 shows the influence of the content of metal silicon powder in Example 1 of the present invention on the apparent porosity and bulk density of the ceramic core.

[0020] Figure 3 shows the influence of different contents of metal silicon powder in Example 1 of the present invention on the thermal expansion of the ceramic core.

[0021] Figure 4 shows the microscopic structure of the cross-section of the ceramic core with different contents of metal silicon powder in Example 1 of the present invention.

[0022] Figure 5 shows the interlayer microscopic structure of the ceramic core with different contents of metal silicon powder in Example 1 of the present invention.

[0023] Figure 6 shows the XRD pattern of the ceramic core with different contents of metal silicon powder in Example 1 of the present invention when sintered at 1200 °C.

[0024] Figure 7 shows the XRD pattern of the ceramic core with different contents of metal silicon powder in Example 1 of the present invention when sintered at 1540 °C.

[0025] Figure 8 shows the cross-sectional microscopic structure of the ceramic core sample with different contents of metal silicon powder in Example 1 of the present invention after being treated at 1540 °C.

[0026] Figure 9is the room temperature flexural strength of the silicon powder content in Example 1 of the present invention for ceramic cores in different directions.

[0027] Figure 10 is the deflection change of ceramic cores with different silicon powder contents in Example 1 of the present invention. Detailed implementation manners

[0028] Example 1

[0029] The preparation method of the 3D printed silicon-based ceramic core in this example is as follows:

[0030] S1. Preparation of the premixed liquid: After mixing 1,6-ethylene glycol diacrylate (HDDA), epoxy acrylate (VE), trimethylolpropane triacrylate (TMPTA), and polyurethane acrylate (PUA), add 2,4,6-trimethylbenzoyl-ethoxy-phenylphosphine oxide (TPO-L), glycerol (GI), and dispersant BYK-111, and stir and mix to obtain the premixed liquid; the premixed liquid is composed of the following raw materials by volume fraction: 25% of 1,6-ethylene glycol diacrylate, 14% of epoxy acrylate, 24% of trimethylolpropane triacrylate, 28% of polyurethane acrylate, 3% of 2,4,6-trimethylbenzoyl-ethoxy-phenylphosphine oxide, 2% of oleic acid, and the balance is dispersant BYK-111;

[0031] Two kinds of powders of fused silica (SiO2, >99.95%, Lianyungang, Jiangsu), white fused alumina (Al2O3, >99.99%, Jiangsu) powder, and zirconium silicate (SiZrO4 >99.99%, Jiangsu);

[0032] The average particle sizes of the powders are D 50 (coarse SiO2) = 22.1 μm, D 50 (fine SiO2) = 4.89 μm, D 50 (Al2O3) = 24.8 μm, D 50 (ZrSiO4) = 23.6 μm, and D 50 (Si) = 5 μm;

[0033] S2. Mix the coarse powder and fine powder of fused quartz powder in a mass ratio of 8:2 to obtain the mixed fused quartz powder, then mix the mixed fused quartz powder with white fused alumina and zirconium silicate in a mass ratio of 17:2:1, and then add metal Si powder, and mix and stir evenly to obtain the mixture; the metal Si powder is 0.4% of the mass of the mixed fused quartz powder; that is, the content of the added metal Si powder in the fused quartz powder mixed according to the mass ratio of the coarse powder to the fine powder of 8:2 is 0.4 wt%);

[0034] In this embodiment, different contents (0wt%, 0.2wt%, 0.6wt%, 0.8wt%, 1.0wt%) of metallic Si powder were added to fused silica powder as a control;

[0035] 0wt%, 0.2wt%, 0.4wt%, 0.8wt%, and 1.0wt% of the metallic Si powder content were respectively named S00, S02, S04, S06, S08, and S10;

[0036] The main component of the metallic Si powder is crystalline silicon (Si), which is a silver-gray or dark-gray powder with a metallic luster. The melting point of the metallic Si powder is around 1410°C, with strong high-temperature resistance. Moreover, the metallic Si powder has a relatively high coefficient of thermal expansion. At the same time, when the Si powder oxidizes into SiO2, it will be accompanied by volume expansion;

[0037] The metallic Si powder in this embodiment was purchased from Mingcheng Metals;

[0038] The component of the metallic silicon powder in this embodiment is crystalline silicon, which is different from silicon powder (the main component is silicon dioxide). In this invention, metallic silicon powder is selected to allow Si to undergo an oxidation reaction. The volume expansion during this process can, to a certain extent, improve the interlayer defects in 3D printing;

[0039] S3. Add the premixed liquid obtained in S1 to the mixture obtained in S2, and ball-mill it for 30 min at a rotation speed of 1200 rpm using a high-speed ball mill (Hefei Kejing, China) to obtain a ceramic slurry with a solid content of 56 vol%;

[0040] S4. Add the ceramic slurry obtained in S3 to a DLP-3D printer (Autocera-M, Beijing Shiwei Technology) to prepare a ceramic core blank. The exposure power of the 3D printer is 23 mW / cm 2 , the exposure time is 6 s, and the slice thickness is 100 μm;

[0041] S5. After the ceramic core blank obtained in S4 is cleaned by an ultrasonic machine and dried, degrease and sinter the blank in a muffle furnace. In order to gently remove the photosensitive resin during the degreasing process, first heat the ceramic core blank from room temperature to 200°C at a heating rate of 1°C / min, then heat it to 204°C at a heating rate of 1°C / min, hold for 1 h, then heat it to 378°C at a heating rate of 1°C / min, hold for 1 h, then heat it to 488°C at a heating rate of 1°C / min, hold for 1 h, then heat it to 600°C at a heating rate of 2°C / min, hold for 1 h, and then heat it to 1200°C at a heating rate of 2°C / min, hold for 6 h, and naturally cool to room temperature to obtain a 3D printed silicon-based ceramic core;

[0042] The shrinkage rates of the prepared 3D printed silicon-based ceramic core in three-dimensional directions are 5.47%, 4.38% and 5.09% respectively, and the bulk density and porosity of the ceramic core are 1.68 g / cm 3 and 28.07% respectively, the interlayer strength and in-layer strength at room temperature are 11.35 MPa and 17.21 MPa respectively, and the high-temperature bending strengths are 8.014 MPa and 10.771 MPa respectively.

[0043] This embodiment also provides an application of the 3D printed silicon-based ceramic core prepared by the above preparation method, and the 3D printed silicon-based ceramic core is used for manufacturing hollow blades.

[0044] In this embodiment, a micrometer is used to measure the length of the ceramic core before and after sintering, and the average value of 4 samples is taken to calculate the linear shrinkage during the sintering process. The Archimedes method is used to evaluate the bulk density and apparent porosity. The bending strength is measured on an Instron testing machine at room temperature and 1540 °C respectively. The particle size distribution of the raw materials is measured using a laser particle size analyzer (MS3000, Malvern), and the surface roughness of the ceramic core is measured using a surface roughness measuring instrument (MarSurf PS1, Mahr). The linear shrinkage rate of the ceramic core is analyzed using a thermal dilatometer (DIL 402, NETZSCH, Germany), and the microstructure of the ceramic core is studied using a scanning electron microscope (SEM, S4800, Hitachi). The phase composition of the ceramic core is revealed using X-ray diffraction (XRD, D8 Advance, Bruker) with a wavelength of 0.154 nm.

[0045] (I) Physical properties

[0046] The relationship between the shrinkage rate of the ceramic core in different directions and the content of metallic silicon powder is as Figure 1 shown. As the silicon content increases from 0 wt% to 1 wt%, the shrinkage rates of the ceramic core in three-dimensional directions first gradually decrease and then rapidly increase. With the addition of metallic silicon powder, the metallic silicon powder undergoes an oxidation reaction to convert into silicon dioxide, and the volume expands, which plays an inhibitory role in the shrinkage rate of the ceramic core. On the other hand, since the melting point of metallic Si powder is about 1410 °C, which is much lower than the melting point of the matrix material SiO2, it plays a role in promoting sintering during the sintering process at 1200 °C, increasing the sintering degree between particles in the core, thereby promoting shrinkage, Figure 1 which is the result of the combined action of the two effects of metallic silicon powder.

[0047] When the content of metallic silicon powder remains unchanged, the shrinkage rate of the ceramic core along the printing direction is significantly higher than that in the layer, showing obvious anisotropy. This is because of the characteristics of layer-by-layer manufacturing of 3D printing technology, which makes the bonding force between layers of the core smaller than the bonding force within the layer. From Figure 1It can be observed that the shrinkage of the Y-axis is significantly lower than that of the X-axis, which is closely related to the ultraviolet scattering phenomenon in the ceramic slurry and the layer-by-layer forming mode of 3D printing. Compared with the designed model, the UV light scattering phenomenon widens the width of the printed green body, so the samples in the Y direction have larger dimensions. However, compared with the designed model, the particles are not tightly connected in the widened area. The loosely connected particles in the widened area resist the shrinkage of the ceramic, resulting in relatively small shrinkage.

[0048] The effects of the content of metallic silicon powder on the apparent porosity and bulk density of ceramic cores are as Figure 2 shown. As the content of metallic silicon powder increases from 0 to 0.4 wt%, the apparent porosity gradually decreases from 29.65% of S00 to 28.07% of S04, and then increases to 32.58% when the content of metallic silicon powder is 1 wt%. The bulk density shows the opposite trend, and the bulk density reaches the maximum value of 1.68 g / cm 3 at a metallic silicon powder content of 0.4 wt%. The apparent porosity and bulk density of the ceramic cores show the same trend as the shrinkage rate.

[0049] To simulate the dimensional changes of ceramic cores during the casting process, thermal expansion tests were carried out on ceramic cores with different contents of metallic silicon powder, as Figure 3 shown. Each colored curve in the figure represents the linear thermal expansion during the entire temperature cycle, including the heating time from room temperature to 1540 °C and the cooling time from 1540 °C to room temperature. All thermal expansion curves show the same trend with the increase in temperature. When the sintering temperature reaches 1100 °C, the ceramic cores soften, resulting in obvious shrinkage. In the cooling stage, as the temperature decreases, the linear shrinkage rate of the ceramic cores gradually increases. When the temperature drops to about 200 °C, a phase transformation from α-cristobalite to β-cristobalite occurs, which leads to the appearance of an inflection point on the thermal expansion curve and greater shrinkage of the ceramic cores. However, with the addition of metallic silicon powder, the linear shrinkage rate of the ceramic cores first gradually decreases and then increases. When the content of metallic silicon powder is S04, the linear shrinkage rate of the specimen is the smallest.

[0050] (2) Microstructure and phase composition

[0051] Figure 4 are the microstructures of the cross-sectional structures of ceramic cores with different contents of metallic silicon powder. In the figure, (a) S00; (b) S02; (c) S04; (d) S06; (e) S08; (f) S10. It can be seen that the fine powder is evenly distributed between the coarse powder, filling the pores between the coarse particles. With the addition of metallic silicon powder, the low melting point of metallic silicon powder plays a role in promoting sintering during the sintering process of the ceramic cores, reducing the number of pores in the ceramic cores, as Figure 4(a-c); As the content of metallic silicon powder continues to increase, due to the volume expansion caused by the oxidation reaction of metallic silicon powder, the densification of the structure of the ceramic core is hindered, resulting in a larger porosity, as Figure 4 (d-f), which is consistent with the change in the apparent porosity of the ceramic core. Figure 5 The interlayer microstructure of ceramic cores with different contents of metallic silicon powder is shown. In the figure, (a) S00; (b) S02; (c) S04; (d) S06; (e) S08; (f) S10. It can be clearly observed that due to the layer-by-layer forming mode of 3D printing, there are obvious interlayer gaps in the ceramic core. And as the content of metallic silicon powder increases from S00 to S04, the interlayer gaps of the specimens gradually disappear. However, as the content of metallic silicon powder continues to increase, the interlayer gaps of the specimens increase rapidly. When the content of metallic silicon powder reaches S10, the interlayer gap of the ceramic core is the most serious. To sum up, when the content of metallic silicon powder is S04, the microstructure effect of the ceramic core is the best.

[0052] Before sintering, the connection between particles in the ceramic core is relatively loose. After sintering, under the action of the sintering driving force, the particles in the ceramic core without adding metallic Si powder are tightly connected, and the gaps between particles are significantly reduced under the action of the sintering driving force. After adding metallic Si powder, some metallic Si powder undergoes oxidation reactions during sintering. The oxidation reaction is accompanied by volume expansion, resulting in a relatively loose connection between the particles of the sintered ceramic core, increasing the pores between the particles, increasing the porosity of the ceramic core, and decreasing the volume density. At the same time, the unoxidized metallic Si powder promotes the sintering of the ceramic core during sintering due to its low melting point, reducing the pores between the particles, decreasing the porosity of the ceramic core, and increasing the volume density.

[0053] The XRD pattern of the ceramic core after sintering at 1200 °C is as Figure 6 shown. Diffraction peaks of zirconium silicate (PDF#06-0266), alumina (PDF#81-1667), and cristobalite (PDF#82-0512) are detected in the XRD pattern, indicating that part of the molten silica is converted into cristobalite during sintering, and the intensity of the diffraction peak of cristobalite does not change significantly. As the content of metallic silicon powder increases, diffraction peaks of silicon (PDF#99-0092) start to be detected in the XRD pattern, and the intensity of the diffraction peak gradually increases with the increase in the content of metallic silicon powder, indicating that the metallic silicon powder is not completely oxidized during sintering. After secondary sintering treatment at 1540 °C, only diffraction peaks of cristobalite and zirconium silicate are detected in the XRD pattern of the ceramic core, indicating that the metallic silicon powder has been completely oxidized to SiO2, as Figure 7 shown.

[0054] Figure 8Figure 0 shows the cross-sectional microstructure of ceramic cores with different metal silicon powder contents after being treated at 1540°C. After the ceramic cores are sintered at high temperature, the quartz glass powder is transformed into cristobalite. Due to the volume change accompanied by the phase transformation from β-cristobalite to α-cristobalite, some microcracks appear in the core samples. During the high-temperature sintering process, the metal silicon powder is completely oxidized to silicon dioxide and its volume expands, inhibiting the expansion of cristobalite cracks. Therefore, it can be seen from the figure that as the content of metal silicon powder increases, the crack size in the microstructure of the core gradually becomes smaller.

[0055] (III) Mechanical Properties

[0056] The room-temperature flexural strength of ceramic cores with different metal silicon powder contents in different directions is as Figure 9 shown in Figure (a). As the content of metal silicon powder increases, both the interlayer and intralayer flexural strengths of the ceramic cores show a trend of first increasing and then decreasing. The interlayer flexural strength increases from 7.74 MPa of S00 to 11.35 MPa of S04 and then decreases to 5.63 MPa of S10; the intralayer flexural strength increases from 16.23 MPa of S00 to 25.33 MPa of S06 and then rapidly decreases to 14.91 MPa of S10, which is consistent with the microstructure of the ceramic cores. And the intralayer flexural strength of the ceramic cores is significantly higher than the interlayer flexural strength because of the anisotropic characteristics of 3D printing, resulting in significantly lower particle bonding force between layers of the core than that within the layers. Figure (b) shows the effect of metal silicon powder content on the high-temperature flexural strength of ceramic cores in different directions. It can be seen from the figure that the sample without metal Si powder has the minimum high-temperature flexural strength, and as the content of metal Si powder increases, the high-temperature flexural strengths of the interlayer and intralayer of the ceramic cores gradually increase. This is because the metal Si powder expands and melts when heated, inhibiting the crack propagation of cristobalite, and the crack size becomes smaller, so the high-temperature flexural strength of the sample increases.

[0057] Figure 10 Figure shows the deflection change of ceramic cores with different metal silicon powder contents. As the content of metal Si powder increases, the high-temperature deformation resistance of the core becomes weaker, and the high-temperature deflection shows an increasing trend. When the metal silicon powder content reaches S08, the deflection of the sample reaches a maximum value of 2.38 mm.

[0058] In summary, the present invention uses stereolithography technology to prepare a silicon-based ceramic core containing metallic Si powder. The experimental results show that as the content of metallic Si powder increases, the shrinkage rate first decreases and then increases, and the room-temperature bending strength and high-temperature bending strength first increase and then decrease. With the addition of metallic silicon powder, the metallic silicon powder undergoes an oxidation reaction to convert into silicon oxide, and the volume expands, which inhibits the shrinkage rate of the ceramic core. On the other hand, since the melting point of metallic Si powder is about 1410 °C, which is much lower than the melting point of the matrix material SiO2, it plays a role in promoting sintering during the sintering process at 1200 °C, increasing the degree of sintering between particles in the core, and thus promoting shrinkage. Therefore, due to the combined effect of the high melting point and high thermal expansion coefficient of metallic Si powder, when the content of metallic Si powder is 0.4 wt%, the performance of the ceramic core reaches the best, and the shrinkage rates in the three-dimensional directions are 5.47%, 4.38%, and 5.09% respectively, and the interlayer strength and in-layer strength at room temperature are 11.35 MPa and 17.21 MPa. Therefore, the optimal addition of metallic Si powder can provide a silicon-based ceramic core with excellent mechanical properties, thereby promoting the application and development of silicon-based ceramic cores in the manufacture of hollow blades.

[0059] The above are only the preferred embodiments of the present invention and do not impose any limitations on the present invention. Any simple modifications, changes, and equivalent variations made to the above embodiments based on the technical essence of the invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A preparation method of a 3D printed silicon-based ceramic core, characterized in that, The method is as follows: S1. Preparation of premixed liquid: After mixing 1,6 - ethylene glycol diacrylate, epoxy acrylate, trimethylolpropane triacrylate and polyurethane acrylate, add 2,4,6 - trimethylbenzoyl - ethoxy - phenylphosphine oxide, oleic acid and dispersant BYK - 111, and stir and mix to obtain the premixed liquid; S2. Mix coarse and fine fused silica powder in a mass ratio of 8:2 to obtain the mixed fused silica powder. Then mix the mixed fused silica powder with white fused alumina and zirconium silicate in a mass ratio of 17:2:1, and then add metallic Si powder. Mix and stir evenly to obtain the mixture. The metallic Si powder is 0.4% of the mass of the mixed fused silica powder. The average particle size of the coarse fused silica powder is 22.1μm, and the average particle size of the fine powder is 4.89μm; S3. Add the premixed liquid obtained in S1 to the mixture obtained in S2, and ball - mill at a speed of 1200 rpm / min for 30 min to obtain the ceramic slurry; S4. Add the ceramic slurry obtained in S3 into a 3D printer to prepare a ceramic core blank. The exposure power of the 3D printer is 23 mW / cm 2 , the exposure time is 6 s, and the slice thickness is 100 μm; S5. After the ceramic core blank obtained in S4 is cleaned by an ultrasonic machine and dried, heat the ceramic core blank from room temperature to 200°C at a heating rate of 1°C / min, then heat it to 204°C at a heating rate of 1°C / min, hold for 1 h, then heat it to 378°C at a heating rate of 1°C / min, hold for 1 h, then heat it to 488°C at a heating rate of 1°C / min, hold for 1 h, then heat it to 600°C at a heating rate of 2°C / min, hold for 1 h, and then heat it to 1200°C at a heating rate of 2°C / min, hold for 6 h, and naturally cool to room temperature to obtain a 3D - printed silicon - based ceramic core; 2. The preparation method of a 3D printed silicon-based ceramic core according to claim 1, wherein The premixed liquid in S1 is composed of raw materials with the following volume fractions: 25% of 1,6 - ethylene glycol diacrylate, 14% of epoxy acrylate, 24% of trimethylolpropane triacrylate, 28% of polyurethane acrylate, 3% of 2,4,6 - trimethylbenzoyl - ethoxy - phenylphosphine oxide, 2% of oleic acid, and the balance is dispersant BYK - 111.

3. The preparation method of a 3D printed silicon-based ceramic core according to claim 1, wherein, The solid content of the ceramic slurry in S3 is 56 vol%.

4. A method for preparing a 3D printed silicon-based ceramic core according to claim 1, characterized in that, The shrinkage rate of the 3D - printed silicon - based ceramic core in three - dimensional directions in S5 is 4.38% - 5.47%, and the inter - layer strength and in - layer strength at room temperature are 11.35 MPa and 17.21 MPa respectively.

5. Use of a 3D printed silicon-based ceramic core prepared by the preparation method according to any one of claims 1-4, characterized in that, The 3D - printed silicon - based ceramic core is used for the manufacture of hollow blades.

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