A high-infrared-emissivity rare-earth nickelate composite 8YSZ ceramic material, a preparation method and application thereof

Abstract

This invention discloses a high infrared emissivity rare-earth nickelate composite 8YSZ ceramic material, its preparation method, and its application, belonging to the technical field of thermal barrier coating ceramic materials. The ceramic material is a two-phase composite ceramic composed of rare-earth nickelate RE2NiO4 and 8YSZ, with the general chemical formula nRE2NiO4-(1-n) 8YSZ; where n is the molar ratio of rare-earth nickelate in the composite system, and the value of n ranges from 0.01≤n≤0.1; RE is selected from La, Pr, and Nd. The ceramic material of this invention has high purity and high infrared emissivity, with an average emissivity of not less than 92% in the 200~2000nm infrared band. The ceramic material of this invention also possesses excellent high-temperature thermal insulation and mechanical wear resistance properties, with a thermal conductivity as low as 1.86~2.0 W·m at 900℃. ‑1 ·K ‑1 It exhibits outstanding high-temperature insulation performance; its Vickers hardness reaches 8.7~10.4 GPa, demonstrating strong resistance to plastic deformation and wear, meeting the requirements for thermal barrier coatings. This invention uses inexpensive oxide powder as raw material, featuring a simple process, low equipment requirements, rapid preparation speed, and no byproduct generation, making it easy for industrial-scale mass production.

Description

Technical Field

[0001] This invention belongs to the technical field of thermal barrier coating ceramic materials, specifically relating to a high infrared emissivity rare earth nickelate composite 8YSZ ceramic material and its preparation method and application. Background Technology

[0002] Thermal barrier coatings (TBCs) are key protective materials for the surfaces of high-temperature components such as aero-engines and gas turbines. They effectively reduce the temperature of the base alloy, increase the operating temperature and service life of hot-end components, and are a core technology for improving the efficiency and reliability of power plants. With the increasing demands for equipment performance in aerospace, energy, and other fields, developing a new generation of thermal barrier coating materials with higher service temperatures (above 1200℃), higher thermal protection efficiency, and superior thermophysical properties has become a key research focus.

[0003] The thermal barrier coating's insulation performance depends not only on its low thermal conductivity but also crucially on its ability to suppress thermal radiation at high temperatures. In high-temperature environments, the contribution of thermal radiation (especially in the near-infrared band, 200–2000 nm) to heat transfer gradually increases with temperature. If the ceramic layer is transparent to infrared radiation or has low emissivity, the heat from the high-temperature combustion gases in the combustion chamber will radiate through the ceramic layer to the metal substrate, causing a "thermal transmission" effect and thus weakening the coating's high insulation performance. Currently, widely researched and applied thermal barrier coating ceramic materials such as 8 mol% yttrium oxide partially stabilized zirconium oxide (8YSZ), rare earth zirconates (RE2Zr2O7), and rare earth tantalates (RETaO4), while having low thermal conductivity, generally have low emissivity in the infrared band, making it difficult to suppress the heat transfer effect of thermal radiation at high temperatures, thus reducing the coating material's thermal insulation performance at high temperatures. To meet the thermal insulation requirements of hot-end components such as aero engines and gas turbines in high-temperature environments (above 1200℃), developing novel thermal barrier coating materials with high infrared emissivity is an important problem that urgently needs to be solved.

[0004] To address the aforementioned problems, this invention aims to provide a high infrared emissivity rare earth nickelate composite 8YSZ ceramic material. Summary of the Invention

[0005] To address the aforementioned problems, the first objective of this invention is to provide a high infrared emissivity rare earth nickelate composite 8YSZ ceramic material, and the second objective of this invention is to provide a method for preparing and applying the high infrared emissivity rare earth nickelate composite 8YSZ ceramic material.

[0006] The first objective of this invention is achieved as follows: a high infrared emissivity rare earth nickelate composite 8YSZ ceramic material, wherein the ceramic material is a two-phase composite ceramic composed of rare earth nickelate RE2NiO4 and 8YSZ, and its general chemical formula is nRE2NiO4-(1-n) 8YSZ; wherein n is the molar ratio of rare earth nickelate in the composite system, and the value of n is in the range of 0.01≤n≤0.1; RE is selected from La, Pr, and Nd.

[0007] The second objective of this invention is achieved by the following steps in the preparation method of the high infrared emissivity rare earth nickelate composite 8YSZ ceramic material: 1) Rare earth oxides and NiO powder are mixed and ball-milled. Agate grinding balls are added, and wet ball milling is performed using anhydrous ethanol as the milling medium to obtain a uniformly mixed ceramic slurry A; the rare earth oxides are La2O3, Nd2O3, or Pr6O. 11 When the rare earth oxide is La₂O₃ or Nd₂O₃, the molar ratio of rare earth oxide to NiO powder is 1:1; when the rare earth oxide is Pr₆O₃... 11 At that time, Pr6O 11 The molar ratio with NiO powder is 1:3; 2) After drying and sieving the ceramic slurry from step 1), it is placed in a muffle furnace for high-temperature solid-state calcination to obtain RE2NiO4 ceramic powder; 3) The obtained RE2NiO4 ceramic powder and 8YSZ ceramic powder are mixed in the molar ratio according to the general formula of the chemical composition of the ceramic material and ball-milled. The ball milling media and anhydrous ethanol are added and wet ball-milled to obtain ceramic slurry B. 4) Dry and sieve the ceramic slurry B, press it into tablets using a tablet press, and then sinter it in a muffle furnace at 1500-1600℃ for 5-10 hours in an air atmosphere. After cooling, the target rare earth nickelate composite 8YSZ ceramic material is obtained.

[0008] The ceramic material is used in the preparation of thermal barrier coatings on the surface of hot-end components of aero-engines or gas turbines.

[0009] The beneficial effects of this invention are as follows: 1. This invention obtains rare earth nickelate composite 8YSZ ceramic material by solid-state reaction sintering. The ceramic material has high purity and high infrared emissivity, with an average emissivity of not less than 92% in the 200~2000nm infrared band.

[0010] 2. The ceramic material of this invention possesses both excellent high-temperature thermal insulation and mechanical wear resistance, with a thermal conductivity as low as 1.86~2.0 W·m at 900℃. -1 ·K -1It has outstanding high-temperature insulation effect; its Vickers hardness can reach 8.7~10.4GPa, and it has strong resistance to plastic deformation and wear resistance, meeting the requirements for use of thermal barrier coatings.

[0011] 3. The ceramic material prepared by this invention can maintain high infrared emissivity within a wide range of raw material ratios, has a wide range of adjustable composition, and the preparation process has good adaptability.

[0012] 4. This invention uses inexpensive oxide powder as raw material, has a simple process, low equipment requirements, fast preparation speed and no by-product generation, and is easy to mass-produce in the industrial sector. Attached Figure Description

[0013] Figure 1 The above are the characterization results of the rare earth nickelate composite 8YSZ ceramic material prepared in Example 1 of this invention. Among them, (a) is the X-ray diffraction pattern, (b) is the emissivity pattern, (c) is the microstructure photograph, (d) is the thermal expansion curve pattern, and (e) is the thermal expansion coefficient curve pattern.

[0014] Figure 2 The above are the characterization results of the rare earth nickelate composite 8YSZ ceramic material prepared in Example 2 of this invention. Among them, (a) is the X-ray diffraction pattern, (b) is the emissivity pattern, (c) is the microstructure photograph, (d) is the thermal expansion curve pattern, and (e) is the thermal expansion coefficient curve pattern.

[0015] Figure 3 The above are the characterization results of the rare earth nickelate composite 8YSZ ceramic material prepared in Example 3 of this invention. Among them, (a) is the X-ray diffraction pattern, (b) is the emissivity pattern, (c) is the microstructure photograph, (d) is the thermal expansion curve pattern, and (e) is the thermal expansion coefficient curve pattern.

[0016] Figure 4 This is the high-temperature thermal conductivity curve of the rare earth nickelate composite 8YSZ ceramic material prepared in Example 1 of this invention.

[0017] Figure 5 This is the high-temperature thermal conductivity curve of the rare earth nickelate composite 8YSZ ceramic material prepared in Example 2 of this invention.

[0018] Figure 6 This is the high-temperature thermal conductivity curve of the rare earth nickelate composite 8YSZ ceramic material prepared in Example 3 of this invention. Detailed Implementation

[0019] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments, but this does not limit the present invention in any way. Any modifications or improvements made based on the teachings of the present invention shall fall within the protection scope of the present invention.

[0020] This invention provides a high infrared emissivity rare earth nickelate composite 8YSZ ceramic material, wherein the ceramic material is a two-phase composite ceramic composed of rare earth nickelate RE2NiO4 and 8YSZ, and its general chemical formula is n RE2NiO4-(1-n)8YSZ; wherein n is the molar ratio of rare earth nickelate in the composite system, and the value of n is 0.01≤n≤0.1; RE is selected from one of La, Pr, and Nd.

[0021] The 8YSZ is a continuous matrix phase, and RE2NiO4 is a doped and modified second phase dispersed in 8YSZ; The ceramic material has a grain size of 0.5–10 μm and a porosity of 0–10%; the ceramic material has an average infrared emissivity of ≥92% in the 200–2000 nm wavelength band.

[0022] This invention also provides a method for preparing the high infrared emissivity rare earth nickelate composite 8YSZ ceramic material, which is implemented according to the following steps: 1) Rare earth oxides and NiO powder are mixed and ball-milled. Agate grinding balls are added, and wet ball milling is performed using anhydrous ethanol as the milling medium to obtain a uniformly mixed ceramic slurry A; the rare earth oxides are La2O3, Nd2O3, or Pr6O. 11 When the rare earth oxide is La₂O₃ or Nd₂O₃, the molar ratio of rare earth oxide to NiO powder is 1:1; when the rare earth oxide is Pr₆O₃... 11 At that time, Pr6O 11 The molar ratio with NiO powder is 1:3; 2) After drying and sieving the ceramic slurry from step 1), it is placed in a muffle furnace for high-temperature solid-state calcination to obtain RE2NiO4 ceramic powder; 3) The obtained RE2NiO4 ceramic powder and 8YSZ ceramic powder are mixed in the molar ratio according to the general formula of the chemical composition of the ceramic material and ball-milled. The ball milling media and anhydrous ethanol are added and wet ball-milled to obtain ceramic slurry B. 4) Dry and sieve the ceramic slurry B, press it into tablets using a tablet press, and then sinter it in a muffle furnace at 1500-1600℃ for 5-10 hours in an air atmosphere. After cooling, the target rare earth nickelate composite 8YSZ ceramic material is obtained.

[0023] In step 1), the ball milling speed is 300-400 rpm and the ball milling time is 10-30 h.

[0024] In step 2), the drying temperature is 70-100℃, and the product is passed through a 200-400 mesh sieve after drying.

[0025] In step 2), the high-temperature solid-phase calcination process is as follows: under an air atmosphere, the reaction is carried out at 1200-1500℃ for 5-10 hours.

[0026] In step 3), the ball milling speed is 300-400 rpm and the ball milling time is 10-30 h.

[0027] In step 4), the pressure for tableting is 200~300MPa, and the holding time is 1~5min.

[0028] The present invention further provides the application of the ceramic material in the preparation of thermal barrier coatings on the surface of hot-end components of aero-engines or gas turbines.

[0029] In the embodiments of the present invention, the purity of both the rare earth oxide powder and the 8YSZ ceramic powder is 99.9%.

[0030] Example 1 This embodiment provides a method for preparing a high infrared emissivity rare earth nickelate composite 8YSZ ceramic material, including the following steps: (1) The two raw materials, rare earth oxide La2O3 and NiO powder, were mixed in anhydrous ethanol at a molar ratio of La2O3:NiO=1:1 and placed in a ball mill jar. Anhydrous ethanol was used as the ball milling medium, and agate grinding balls were added for wet ball milling. The ball milling speed was 300 rpm and the ball milling time was 20 h to obtain a uniformly mixed ceramic slurry A. (2) After drying ceramic slurry A at 70°C for 30 hours in air atmosphere, it is sieved through a 200-mesh sieve to obtain dry powder. The dry powder is then placed in a muffle furnace for sintering: in air atmosphere, the temperature is increased from 50°C to 1000°C at 8°C / min and held for 30 minutes, then increased to 1200°C at 5°C / min and held for 30 minutes, and then increased to 1400°C at 4°C / min and held for 600 minutes to carry out high-temperature solid-state calcination reaction; after sintering, the temperature is reduced to 500°C at 3°C / min, and then naturally cooled with the furnace to obtain La2NiO4 ceramic powder. (3) The obtained La2NiO4 ceramic powder and 8YSZ ceramic powder were mixed in anhydrous ethanol at a molar ratio of La2NiO4:8YSZ=5:95. Agate grinding balls were added and anhydrous ethanol were added and the mixture was wet-milled at 300 rpm for 20 h to obtain ceramic slurry B. (4) After drying ceramic slurry B at 70°C for 30 hours in air atmosphere, it is sieved through a 200-mesh sieve to obtain dry powder. It is then placed in a tablet press to press into tablets at a pressure of 250 MPa and a holding time of 3 minutes to obtain bulk raw material. (5) Sintering the bulk raw material in a muffle furnace: Under an air atmosphere, the temperature is increased from 50℃ to 1000℃ at 8℃ / min and held for 30min, then increased to 1200℃ at 5℃ / min and held for 30min, and then increased to 1400℃ at 4℃ / min and held for 600min, so that the bulk raw material undergoes a solid-phase reaction; after sintering, the temperature is reduced to 500℃ at 3℃ / min, and then naturally cooled with the furnace to obtain a rare earth nickelate composite 8YSZ ceramic material with a grain size of 0.5~10μm, a porosity of 8.34%, and an average emissivity of 94.71% in the 200~2000nm infrared band. Its chemical expression is 0.05La2NiO4-(0.95)8YSZ.

[0031] X-ray diffraction pattern ( Figure 1 (a) As can be seen, the obtained ceramic material has an orthorhombic perovskite structure and no obvious impurity phases. Emissivity test results ( Figure 1 (b) shows that the ceramic material has an average emissivity of 94.71% in the wavelength range of 200–2000 nm, exhibiting high infrared emission performance. From the microstructure ( Figure 1 (c) It can be observed that the ceramic material has good sintering density, relatively uniform grain size distribution, and clear and complete grain boundaries.

[0032] Example 2 This embodiment provides a method for preparing a high infrared emissivity rare earth nickelate composite 8YSZ ceramic material, including the following steps: (1) Rare earth oxide Pr6O 11 NiO powder and Pr6O are two raw materials used in a molar ratio of 1:1:1:2:1:2:3 ...3:2:3:3:3:3:3:2:3:3:3:3:3:3:3 11 NiO was mixed in anhydrous ethanol at a ratio of 1:3 and placed in a ball mill jar. Anhydrous ethanol was used as the ball milling medium, and agate grinding balls were added for wet ball milling. The ball milling speed was 300 rpm and the ball milling time was 20 h to obtain a uniformly mixed ceramic slurry A. (2) After drying ceramic slurry A at 70°C for 30 hours in air atmosphere, it is sieved through a 200-mesh sieve to obtain dry powder. The dry powder is then placed in a muffle furnace for sintering: in air atmosphere, the temperature is increased from 50°C to 1000°C at 8°C / min and held for 30 minutes, then increased to 1200°C at 5°C / min and held for 30 minutes, and then increased to 1400°C at 4°C / min and held for 600 minutes to carry out high-temperature solid-state calcination reaction; after sintering, the temperature is reduced to 500°C at 3°C / min, and then naturally cooled with the furnace to obtain Pr2NiO4 ceramic powder. (3) The obtained Pr2NiO4 ceramic powder and 8YSZ ceramic powder were mixed in anhydrous ethanol at a molar ratio of Pr2NiO4:8YSZ=5:95. Agate grinding balls and anhydrous ethanol were added and wet ball milled at 350 rpm for 15 h to obtain ceramic slurry B. (4) After drying ceramic slurry B at 70°C for 30 hours in air atmosphere, it is sieved through a 200-mesh sieve to obtain dry powder. It is then placed in a tablet press to press it into tablets at a pressure of 200 MPa and a holding time of 3 minutes to obtain bulk raw material. (5) Sintering the bulk raw material in a muffle furnace: Under an air atmosphere, the temperature is increased from 50℃ to 1000℃ at 8℃ / min and held for 30min, then increased to 1200℃ at 5℃ / min and held for 30min, and then increased to 1400℃ at 4℃ / min and held for 600min, so that the bulk raw material undergoes a solid-phase reaction; after sintering, the temperature is reduced to 500℃ at 3℃ / min, and then naturally cooled with the furnace, thus obtaining a rare earth nickelate composite 8YSZ ceramic material with a grain size of 0.5~10μm, a porosity of 5.58%, and an average emissivity of 92.62% in the 200~2000nm infrared band. Its chemical expression is 0.05Pr2NiO4-(0.95)8YSZ. From the X-ray diffraction pattern ( Figure 2 (a) As can be seen, the obtained ceramic material has an orthorhombic perovskite structure and no obvious impurity phases. Emissivity test results ( Figure 2 (b) shows that the ceramic material has an average emissivity of 92.62% in the wavelength range of 200–2000 nm, exhibiting high infrared emission performance. From the microstructure ( Figure 2 (c) It can be observed that the ceramic material has good sintering density, relatively uniform grain size distribution, and clear grain boundaries.

[0033] Example 3 This embodiment provides a method for preparing a high infrared emissivity rare earth nickelate composite 8YSZ ceramic material, including the following steps: (1) Two raw materials, rare earth oxide Nd2O3 and NiO powder, were mixed in anhydrous ethanol at a molar ratio of Nd2O3:NiO=1:1 and placed in a ball mill jar. Anhydrous ethanol was used as the ball milling medium, and agate grinding balls were added for wet ball milling. The ball milling speed was 300 rpm and the ball milling time was 20 h to obtain a uniformly mixed ceramic slurry A. (2) After drying ceramic slurry A at 70°C for 30 hours in air atmosphere, it is sieved through a 200-mesh sieve to obtain dry powder. The dry powder is then placed in a muffle furnace for sintering: in air atmosphere, the temperature is increased from 50°C to 1000°C at 8°C / min and held for 30 minutes, then increased to 1200°C at 5°C / min and held for 30 minutes, and then increased to 1400°C at 4°C / min and held for 600 minutes to carry out high-temperature solid-state calcination reaction; after sintering, the temperature is reduced to 500°C at 3°C / min, and then naturally cooled with the furnace to obtain Nd2NiO4 ceramic powder. (3) The obtained Nd2NiO4 ceramic powder and 8YSZ ceramic powder were mixed in anhydrous ethanol at a molar ratio of Nd2NiO4:8YSZ=5:95. Agate grinding balls were added and anhydrous ethanol were added and the mixture was wet-milled at 400 rpm for 28 h to obtain ceramic slurry B. (4) After drying ceramic slurry B at 70°C for 30 hours in air atmosphere, it is sieved through a 200-mesh sieve to obtain dry powder. It is then placed in a tablet press to press it into tablets at a pressure of 300 MPa and a holding time of 3 min to obtain bulk raw material. (5) Sintering the bulk raw material in a muffle furnace: Under an air atmosphere, the temperature is increased from 50℃ to 1000℃ at 8℃ / min and held for 30min, then increased to 1200℃ at 5℃ / min and held for 30min, and then increased to 1400℃ at 4℃ / min and held for 600min, so that the bulk raw material undergoes a solid-phase reaction; after sintering, the temperature is reduced to 500℃ at 3℃ / min, and then naturally cooled with the furnace, thus obtaining a rare earth nickelate composite 8YSZ ceramic material with a grain size of 0.5~10μm, a porosity of 2.68%, and an average emissivity of 92.64% in the 200~2000nm infrared band. Its chemical expression is 0.05Nd2NiO4-(0.95)8YSZ. From the X-ray diffraction pattern ( Figure 3 (a) As can be seen, the obtained ceramic material has an orthorhombic perovskite structure and no obvious impurity phases. Emissivity test results ( Figure 3 (b) shows that the ceramic material has an average emissivity of 92.64% in the wavelength range of 200–2000 nm, exhibiting high infrared emission performance. From the microstructure ( Figure 3 (c) It can be observed that the ceramic material has good sintering density, relatively uniform grain size distribution, and clear grain boundaries.

[0034] Test Example 1: Thermal expansion properties of ceramic materials prepared in Examples 1-3 Testing method: The ceramic materials prepared in Examples 1-3 were wire-cut into strip-shaped blocks of 3mm × 3mm × 12mm, and the surfaces were polished. The samples were then placed in a thermal expansion meter (DIL402, Netzsch, Germany) and heated from room temperature to 1200℃. The linear expansion rate and coefficient of linear expansion of the samples were recorded.

[0035] Results analysis: Depend on Figures 1-3 It can be seen that the ceramic materials obtained in Examples 1-3 did not undergo phase transformation within a wide temperature range. Figure 1 No internal cracking due to thermal mismatch was observed in samples d, 2d, and 3d, indicating excellent high-temperature thermal stability. At 1200℃, the coefficients of thermal expansion of Examples 1-3 were 14.8 × 10⁻⁶. -6 / K, 15.0×10 -6 / K and 15.1×10 -6 / K ( Figure 1 e, 2e and 3e), all of which are related to the high-temperature alloy matrix (12~18×10). -6 The fact that the K) is close to the surface indicates that the ceramic material prepared by this invention has good thermal matching performance with the high-temperature alloy matrix.

[0036] Test Example 2: High-temperature thermal conductivity of ceramic materials prepared in Examples 1-3 Testing Method: The ceramic materials prepared in Examples 1-3 were wire-cut into circular samples with a diameter of 6 mm and a thickness of 1.5 mm, and the surface was carbon-sprayed. The samples were placed in a laser thermal conductivity meter (LFA427, Netzsch, Germany) and heated from room temperature to 1200 °C. The thermal diffusivity of the samples was measured every 100 °C. λ Sample heat capacity ( ). C p The density is calculated using the NK rule. d The thermal conductivity of the sample was obtained using Archimedes' displacement method. k It can be obtained through the following formula: k = λ · C p · d Results analysis: from Figure 4-6 It can be seen that the thermal conductivity of the ceramic material samples prepared in Examples 1-3 at 900℃ is 2.0 W·m. -1 ·K -1 1.98 W·m -1 ·K -1 and 1.86 W·m -1 ·K -1All of them exhibited low high-temperature thermal conductivity, indicating that the ceramic material prepared by the present invention has good high-temperature thermal insulation performance in high-temperature environments.

[0037] Test Example 3: Vickers hardness of ceramic materials prepared in Examples 1-3 Testing Method: The ceramic materials prepared in Examples 1-3 were mirror-polished with sandpaper, and the polished samples were ultrasonically cleaned and dried. Vickers indentation tests were performed on the polished sample surfaces using a micro Vickers hardness tester (HMV-G-FA, Shimadzu, Japan). The pressure (…) F The pressure was 9.8 N, and the holding time was 10 seconds. After the holding time was completed, the diagonal length of the indentation was measured. d The Vickers hardness of the samples was obtained according to the instrument's built-in standard Vickers hardness calculation program. Each sample was measured three times at different locations, and the average value was taken. The distance between each measurement point was 1~2mm. The results are shown in Table 1.

[0038] Table 1. Vickers hardness test values ​​of samples from Examples 1-3

[0039] Results analysis: The Vickers hardness test results of the ceramic materials obtained in Examples 1-3 are shown in Table 1. As can be seen from Table 1, the Vickers hardnesses of the three groups of samples are 10.4 GPa, 9.4 GPa, and 8.7 GPa, respectively. All three materials exhibit high hardness values, close to those of commercially available 8YSZ thermal barrier coated ceramics, indicating that the ceramic materials prepared in this invention have good resistance to deformation and wear, and can meet the requirements of thermal barrier coatings for the mechanical properties of the ceramic layer.

[0040] The specific embodiments of the present invention have been described in detail above, but these are merely examples, and the present invention is not limited to the specific embodiments described above. For those skilled in the art, any equivalent modifications or substitutions to the invention are also within the scope of the present invention. Therefore, all equivalent transformations, modifications, and improvements made without departing from the spirit and principles of the present invention should be covered within the scope of the present invention.

Claims

1. A high infrared emissivity rare earth nickelate composite 8YSZ ceramic material, characterized in that, The ceramic material is a two-phase composite ceramic composed of rare earth nickelates RE2NiO4 and 8YSZ, with the general chemical formula n RE2NiO4-(1-n) 8YSZ; where n is the molar ratio of rare earth nickelates in the composite system, and the value of n ranges from 0.01 to n ≤ 0.1; RE is selected from one of La, Pr, and Nd.

2. The high infrared emissivity rare earth nickelate composite 8YSZ ceramic material according to claim 1, characterized in that, The 8YSZ is a continuous matrix phase, and RE2NiO4 is a doped and modified second phase dispersed in 8YSZ; The ceramic material has a grain size of 0.5–10 μm and a porosity of 0–10%; the ceramic material has an average infrared emissivity of ≥92% in the 200–2000 nm wavelength band.

3. The preparation method of the high infrared emissivity rare earth nickelate composite 8YSZ ceramic material according to claim 1, characterized in that, Follow these steps to achieve the following: 1) Rare earth oxides and NiO powder are mixed and ball-milled. Agate grinding balls are added, and wet ball milling is performed using anhydrous ethanol as the grinding medium to obtain a uniformly mixed ceramic slurry A; the rare earth oxides are La2O3, Nd2O3, or Pr6O. 11 When the rare earth oxide is La₂O₃ or Nd₂O₃, the molar ratio of rare earth oxide to NiO powder is 1:1; when the rare earth oxide is Pr₆O₃... 11 At that time, Pr6O 11 The molar ratio with NiO powder is 1:3; 2) After drying and sieving the ceramic slurry from step 1), it is placed in a muffle furnace for high-temperature solid-state calcination to obtain RE2NiO4 ceramic powder; 3) The obtained RE2NiO4 ceramic powder and 8YSZ ceramic powder are mixed in the molar ratio according to the general formula of the chemical composition of the ceramic material and ball-milled. The ball milling media and anhydrous ethanol are added and wet ball-milled to obtain ceramic slurry B. 4) Dry and sieve the ceramic slurry B, press it into tablets using a tablet press, and then sinter it in a muffle furnace at 1400℃ for 5-10 hours in an air atmosphere. After cooling, the target rare earth nickelate composite 8YSZ ceramic material is obtained.

4. The preparation method according to claim 3, characterized in that, In step 1), the ball milling speed is 300-400 rpm and the ball milling time is 10-30 h.

5. The preparation method according to claim 3, characterized in that, In step 2), the drying temperature is 70-100℃, and the product is passed through a 200-400 mesh sieve after drying.

6. The preparation method according to claim 3, characterized in that, In step 2), the high-temperature solid-phase calcination process is as follows: under an air atmosphere, the reaction is carried out at 1400℃ for 5 to 10 hours.

7. The preparation method according to claim 3, characterized in that, In step 3), the ball milling speed is 300-400 rpm and the ball milling time is 10-30 h.

8. The preparation method according to claim 3, characterized in that, In step 4), the pressure for tableting is 200~300MPa, and the holding time is 1~5min.

9. The application of the ceramic material of claim 1 or 2 in the preparation of thermal barrier coatings on the surface of hot-end components of aero-engines or gas turbines.

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