Preparation method of high-strength and tough / low thermal conductivity / anti-thermal radiation penetration integrated thermal barrier ceramic coating

Abstract

A preparation method of an integrated thermal barrier ceramic coating with high strength and toughness / low thermal conductivity / anti-thermal radiation penetration belongs to the technical field of thermal barrier coating materials. The purpose of the present invention is to solve the problems that the anti-thermal radiation penetration thermal barrier coating materials prepared by the existing methods have precious metal second phases which are not only expensive but also have a large difference in thermal expansion coefficients between the metal-doped second phases and the ceramic matrix phases, resulting in the failure of thermal expansion matching of the materials at high temperatures, the metal-doped second phases have high thermal conductivities, which will increase the thermal conductivity of the composite materials and reduce their thermal protection effects during high-temperature service, and there are potential problems of interface failure in the multi-layer structure coatings. Method: First, surface pretreatment of the substrate; second, preparation of the bonding layer; third, preparation of the ceramic matrix phase components and the dispersed phase functional ceramic components; fourth, mixing and spherical granulation; fifth, preparation of the functional surface layer. The present invention can obtain an integrated thermal barrier ceramic coating with high strength and toughness / low thermal conductivity / anti-thermal radiation penetration.

Description

Technical Field

[0001] The present invention belongs to the technical field of thermal barrier coating materials, and in particular relates to a method for preparing a high-toughness / low-thermal-conductivity / thermal-radiation-resistant integrated thermal barrier ceramic coating. Background Art

[0002] Thermal barrier coatings are key technologies for protecting the hot end components of turbines for stable operation and developing high thrust-to-weight ratio turbine engines and high-efficiency heavy-duty gas turbines. At present, research on thermal barrier coating materials at home and abroad mainly focuses on reducing the thermal conductivity of materials and improving the high-temperature stability of thermal barrier coating materials, and has developed a series of high-temperature resistant and low-thermal conductivity oxide ceramic coating material systems such as niobates, hafnates, tannates and zirconates; however, a key common bottleneck problem restricting the application of the above oxide systems in high-temperature gas environments is that oxide thermal barrier ceramics such as niobates have high infrared transmittance (transmittance>0.5) and poor high-temperature thermal radiation shielding performance. As the gas temperature>1200℃, the heat flux density in the main radiation band of the gas (0.3-10μm) will reach 2300000W·m -2 At this time, the thermal radiation penetration increment of the coating will cause a strong thermal shock to the substrate, and low thermal conductivity alone can no longer meet the urgent needs of the new generation of ultra-high temperature turbine systems. At present, research on high-temperature thermal radiation shielding of thermal barrier ceramic coatings is in its infancy and is very scarce.

[0003] At the end of 2022, a Chinese patent (CN 115233069 A) disclosed a composite ceramic material in which platinum micron flakes are arranged in parallel and distributed in a rare earth zirconate ceramic matrix, as well as its preparation method and application. In the same year, a Chinese patent (CN 115010492 A) similarly disclosed a noble metal nanoparticle uniformly dispersed in a ceramic matrix to reduce the infrared transmittance of the ceramic. However, the structural design proposed is limited to the design and preparation of ceramic block materials, and the noble metal second phase is not only expensive but also has the following series of problems. (1) The thermal expansion coefficients between the metal-doped second phase and the ceramic matrix phase are very different, which easily leads to failure of the thermal expansion matching of the material at high temperatures; (2) The metal-doped second phase has a high thermal conductivity, which will increase the thermal conductivity of the composite material and reduce its thermal protection effect under high-temperature service. In addition, there are some potential problems in improving the reflectivity and radiation penetration resistance of the coating through a multilayer structure. Matthew J. Kelly of Pennsylvania State University in the United States used YSZ-Al 2 O 3 The multi-layer coating structure design and construction can improve the spectral reflectivity of the coating to 0.8, but it is prone to the hidden danger of interface failure. Therefore, it is urgent to develop an integrated thermal barrier ceramic coating system with strong toughness / low thermal conductivity / anti-thermal radiation penetration and its preparation method. Summary of the invention

[0004] The object of the present invention is to solve the problems existing in the anti-thermal radiation penetrating thermal barrier coating material prepared by the existing method, that is, the noble metal second phase is not only expensive, but also the difference in thermal expansion coefficient between the metal-doped second phase and the ceramic matrix phase is very large, resulting in the failure of thermal expansion matching of the material at high temperature. The metal-doped second phase has a high thermal conductivity, which will increase the thermal conductivity of the composite material, reduce its thermal protection effect during high-temperature service, and there is a potential problem of interface failure in the multi-layer structure coating. Therefore, a preparation method of a high-strength and toughness / low thermal conductivity / anti-thermal radiation penetrating integrated thermal barrier ceramic coating is provided.

[0005] A preparation method of a high-strength and toughness / low thermal conductivity / anti-thermal radiation penetrating integrated thermal barrier ceramic coating is completed according to the following steps:

[0006] I. Substrate surface pretreatment:

[0007] First, remove the oxide film and grease on the substrate surface, then roughen the substrate surface, and finally perform thermal spraying preheating treatment on the substrate surface.

[0008] II. Preparation of the bonding layer:

[0009] Spray the bonding layer powder onto the workpiece surface by using the atmospheric plasma spraying process to obtain a substrate with a bonding layer.

[0010] III. Preparation of the ceramic matrix phase component and the dispersed phase functional ceramic component:

[0011] Prepare the ceramic matrix phase component and the dispersed phase functional ceramic component by using the sol-gel or solid-phase reaction method.

[0012] IV. Mixing and spherical granulation of the functional ceramic powder:

[0013] Weigh the ceramic matrix phase component and the dispersed phase functional ceramic component according to the ratio, and then perform powder mixing and spherical granulation treatment on the weighed ceramic matrix phase component and the dispersed phase functional ceramic component to obtain a spherical composite feed.

[0014] V. Preparation of the high-strength and toughness / low thermal conductivity / anti-radiation penetration functional surface layer:

[0015] Adopt the plasma spraying method to spray the spherical composite feed onto the surface of the substrate with a bonding layer, and prepare a high-strength and toughness / low thermal conductivity / anti-radiation penetration functional surface layer on the substrate surface to obtain a high-strength and toughness / low thermal conductivity / anti-thermal radiation penetrating integrated thermal barrier ceramic coating.

[0016] The principle of the present invention:

[0017] The present invention designs and prepares a composite coating of a microporous and functionally dispersed phase distributed in a matrix thermal barrier ceramic by means of electrospray or spray granulation-thermal spraying; wherein, a certain amount of pore-forming agent is introduced in the electrospray and spray granulation processes to obtain a porous feed, and then micropores are introduced into the coating; due to the large difference in dielectric function between the micropores (air), the scattered second phase and the matrix ceramic, and by controlling the size of the scattered second phase (micropores) to be between 0.3 and 10 μm and the volume fraction to be between 5 and 50%, strong optical backscattering can be achieved at the interface with the matrix phase. When the thickness of the coating is between 20 and 500 μm, the infrared reflectivity of the coating in the 0.3-10 μm band is greater than 0.8, and the infrared transmittance is less than 0.15; the difference in thermal expansion coefficient between the functionally dispersed phase ceramic component and the ceramic matrix phase component is less than 1.5×10 -6 K -1 , enabling good thermal expansion matching at the interface between the functionally dispersed phase ceramic component and the ceramic matrix phase component, and avoiding interface damage and failure caused by thermal shock at high and low temperatures; the functionally dispersed phase ceramic component has the characteristics of high-temperature ferroelastic phase transformation and can play a role in toughening by phase transformation. Finally, the thermal conductivity of the ceramic matrix phase component is less than 3 W / (m·K), the thermal conductivity of the functionally dispersed phase ceramic component is less than 5 W / (m·K), and together with the effect of the micropores, the overall thermal conductivity of the coating can be ensured to be less than 1 W / (m·K).

[0018] Advantages of the present invention:

[0019] 1. A high-strength, high-toughness / low-thermal-conductivity / anti-thermal-radiation-penetration integrated thermal barrier ceramic coating prepared by the present invention breaks through the problems of high cost, high thermal conductivity, poor thermal expansion coefficient matching with the matrix ceramic phase, resulting in a decline in thermal protection performance, and easy interface damage and failure at high temperatures compared with the existing noble metal-ceramic composite system; compared with the existing multi-layer structure coating scheme, its particle-dispersed coating structure system not only has a simpler preparation method but also breaks through the hidden danger of damage and failure of multiple interfaces under thermal stress.

[0020] 2. The present invention has low cost and simple operation. The low thermal conductivity and anti-radiation penetration of the material can be achieved through the thermal spraying process. The material has good structural properties, good thermal expansion matching, strong stability, and high environmental adaptability. Therefore, a high-strength, high-toughness / low-thermal-conductivity / anti-thermal-radiation-penetration integrated thermal barrier ceramic coating provided by the present invention has good application prospects.

[0021] 3. The thermal conductivity of the high-strength, high-toughness / low-thermal-conductivity / anti-thermal-radiation-penetration integrated thermal barrier ceramic coating prepared by the present invention is less than 1 W / (m·K), the bonding strength is greater than 25 MPa, the hardness is greater than 2.5 GPa, and the fracture toughness is greater than 2.5 MPa·m 1 / 2 , the infrared reflectivity in the 0.3-10 μm band is greater than 0.8, and the infrared transmittance is less than 0.15. Description of the drawings

[0022] Figure 1 Schematic diagram of the structure of the micropores and functional dispersion phases described in the present invention distributed in the low-thermal-conductivity matrix phase to form a high-strength and toughness / low-thermal-conductivity / anti-thermal-radiation penetration integrated thermal barrier ceramic coating;

[0023] Figure 2 Morphology diagram of the spherical porous electrospray granulation feed powder prepared in Step 4 of Example 1;

[0024] Figure 3 XRD pattern, where 1 is Y 3 NbO 7 , 2 is GdTaO 4 , 3 is Y 3 NbO 7 -GdTaO 4 High-strength and toughness / low-thermal-conductivity / anti-thermal-radiation penetration integrated thermal barrier ceramic coating;

[0025] Figure 4 SEM image of the surface of the Y 3 NbO 7 -GdTaO 4 High-strength and toughness / low-thermal-conductivity / anti-thermal-radiation penetration integrated thermal barrier ceramic coating prepared in Step 5 of Example 1;

[0026] Figure 5 SEM image of the ferroelastic domain structure of GdTaO 3 NbO 7 -GdTaO 4 in the high-strength and toughness / low-thermal-conductivity / anti-thermal-radiation penetration integrated thermal barrier ceramic coating prepared in Step 5 of Example 1; 4 Ferroelastic domain structure diagram;

[0027] Figure 6 Cross-sectional morphology of the Y 3 NbO 7 -GdTaO 4 High-strength and toughness / low-thermal-conductivity / anti-thermal-radiation penetration integrated thermal barrier ceramic coating prepared in Step 5 of Example 1;

[0028] Figure 7 Spectral reflectivity pattern of the coating, where 1 is Y 3 NbO 7 , 2 is the Y 3 NbO 7 -GdTaO 4 High-strength and toughness / low-thermal-conductivity / anti-thermal-radiation penetration integrated thermal barrier ceramic coating prepared in Step 5 of Example 1. Specific embodiments

[0029] Embodiment 1: A method for preparing a high-strength and tough / low thermal conductivity / anti-thermal radiation penetration integrated thermal barrier ceramic coating is completed according to the following steps:

[0030] I. Substrate surface pretreatment:

[0031] First, remove the oxide film and grease on the substrate surface, then roughen the substrate surface, and finally perform thermal spraying preheating treatment on the substrate surface;

[0032] II. Preparation of the bonding layer:

[0033] Spray the bonding layer powder onto the workpiece surface by using the atmospheric plasma spraying process to obtain a substrate with a bonding layer;

[0034] III. Preparation of the ceramic matrix phase component and the dispersed phase functional ceramic component:

[0035] Prepare the ceramic matrix phase component and the dispersed phase functional ceramic component by using the sol-gel or solid-phase reaction method;

[0036] IV. Mixing and spherical granulation of the functional ceramic powder:

[0037] Weigh the ceramic matrix phase component and the dispersed phase functional ceramic component according to the ratio, and then perform powder mixing and spherical granulation treatment on the weighed ceramic matrix phase component and the dispersed phase functional ceramic component to obtain a spherical composite feed;

[0038] V. Preparation of the high-strength and tough / low thermal conductivity / anti-radiation penetration functional surface layer:

[0039] Spray the spherical composite feed onto the surface of the substrate with a bonding layer by using the plasma spraying method to prepare a high-strength and tough / low thermal conductivity / anti-radiation penetration functional surface layer on the substrate surface, and obtain a high-strength and tough / low thermal conductivity / anti-thermal radiation penetration integrated thermal barrier ceramic coating.

[0040] Embodiment 2: The difference between this embodiment and Embodiment 1 is that: in Step I, the substrate is a metal matrix material or a ceramic matrix material; the metal matrix material is a titanium aluminum alloy, a nickel-based alloy or a niobium-based alloy; the ceramic matrix material is C / C, SiC / SiC, C / SiC or SiC / Si 3 N 4; In Step 1, the method for removing the oxide film and grease on the substrate surface is to polish the substrate with sandpaper to remove the oxide film, and then use one or several of the solvent cleaning method, steam cleaning method, alkali cleaning method, and heating degreasing method to remove the substrate grease; the method for roughening the substrate surface in Step 1 is sandblasting or laser texturing. When the substrate is a metal-based material, sandblasting is used, and when the substrate is a ceramic-based material, laser texturing is used; the parameters of the sandblasting are: the sand grain size is 15 - 50 mesh, and the sandblasting pressure is 0.3 - 0.7 MPa; the laser texturing parameters are: the laser power is 1 - 8 kW, the pulse frequency is 10 - 20 Hz, the spot size is 10 - 100 μm, and the roughness of the textured substrate surface is 1 - 5 μm; the preheating temperature of the thermal spraying in Step 1 is 600 - 900 °C. Other steps are the same as those in Specific Embodiment 1.

[0041] Specific Embodiment 3: The difference between this embodiment and one of Specific Embodiments 1 or 2 is: The bonding layer powder in Step 2 needs to be selected according to the type of the substrate. When the substrate is a metal-based material, the bonding layer powder is selected as MCrAlY, where M is Ni, Co, or NiCo; when the substrate is laser textured, the bonding layer powder is selected as RE-Si, where RE is a rare earth element, and the rare earth element is Hf or Y; the process of the atmospheric plasma spraying in Step 2 is: the current is 600 A - 650 A, the main gas flow is 40 - 50 slpm, the auxiliary gas flow is 3 - 10 slpm, the carrier gas flow is 1 slpm - 5 slpm, and the powder feeding rate is 1 - 3 rpm; the thickness of the bonding layer on the substrate with the bonding layer in Step 2 is 20 μm - 200 μm. Other steps are the same as those in Specific Embodiment 1 or 2.

[0042] Specific Embodiment 4: The difference between this embodiment and one of Specific Embodiments 1 to 3 is: There is a large difference in the dielectric function N between the ceramic matrix phase component and the dispersed phase functional ceramic component, that is, the absolute value of the difference in the refractive index n between the ceramic matrix phase component and the dispersed phase functional ceramic component needs to be greater than 0.3 or the absolute value of the difference in the extinction coefficient k between the ceramic matrix phase component and the dispersed phase functional ceramic component needs to be greater than 1; the dielectric function N = n + ik, where n is the refractive index of the ceramic, i is the imaginary unit symbol; k is the extinction coefficient of the ceramic. Other steps are the same as those in Specific Embodiments 1 to 3.

[0043] Specific Embodiment 5: The difference between this embodiment and one of Specific Embodiments 1 to 4 is: The absolute value of the difference in the thermal expansion coefficient between the ceramic matrix phase component and the dispersed phase functional ceramic component in Step 3 is less than 1.5×10 -6 K -1; the thermal conductivity of the ceramic matrix component described in step three is less than 3 W / (m·K); the ceramic matrix component is yttria-stabilized zirconia (YSZ) or rare earth niobate (RE 3 NbO 7 )、zirconate (RE 3 Zr 2 O 7 ) or hafniumate (RE 3 Zr 2 O 7 ); the dispersed phase functional ceramic component described in step three is a ceramic component with high-temperature ferroelastic phase transition characteristics and a low thermal conductivity less than 5 W / (m·K); the dispersed phase functional ceramic component is rare earth tantalate or aluminate. Other steps are the same as those in the first to fourth specific embodiments.

[0044] Specific embodiment six: The difference between this embodiment and any one of the first to fifth specific embodiments is that: the ceramic matrix component and the dispersed phase functional ceramic component described in step three belong to different crystal systems, and there is no infinite solid solution effect between the two phases; the powder particle size of the ceramic matrix component prepared in step three is 1 - 10 μm, and the powder particle size of the dispersed phase functional ceramic component is less than 3 μm. Other steps are the same as those in the first to fifth specific embodiments.

[0045] Specific embodiment seven: The difference between this embodiment and any one of the first to sixth specific embodiments is that: the molar ratio of the ceramic matrix component and the dispersed phase functional ceramic component described in step four is (3 - 20):1; the process of powder mixing and spherical granulation treatment in step four does not distinguish the order; when powder mixing is carried out first and then spherical granulation treatment, the mixing process is as follows: put the original powders of the matrix phase and the dispersed functional phase, absolute ethanol, and zirconia balls into a planetary ball mill tank according to a mass ratio of 1:0.1:3, ball mill at a speed of 200 r / min - 400 r / min for 6 h - 12 h to obtain the original powder mixed slurry, then dry the slurry at 60°C - 120°C for 3 h - 12 h to obtain the original ceramic powder with uniform mixing of the matrix phase and the dispersed phase, and then carry out spherical granulation treatment on the mixed original powder; when spherical granulation treatment is carried out first and then mixing, the mixing process of the granulated powder is as follows: adopt the ordinary dry ball milling method, put the spherical matrix phase and dispersed phase powders into an ordinary ball mill tank according to the ratio, and ball mill at a ball-to-material ratio of 1:0.1 and a speed of 150 r / min for 3 h to obtain the uniformly mixed spherical granulated ceramic powder. Other steps are the same as those in the first to sixth specific embodiments.

[0046] Embodiment 8: The difference between this embodiment and any one of Embodiments 1 to 7 is that: the spherical granulation method described in Step 4 is one or both of electrospray granulation and spray granulation; the particle size of the spherical composite powder feed described in Step 4 is 1 to 100 μm. Other steps are the same as those in Embodiments 1 to 7.

[0047] Embodiment 9: The difference between this embodiment and any one of Embodiments 1 to 8 is that: the electrospray granulation process described in Step 4 is completed according to the following steps:

[0048] ①. Prepare electrospray slurry:

[0049] Disperse the mixed ceramic powder in an aqueous dispersant, then ultrasonicate for 30 to 100 min, add a pore-forming agent, and heat and stir in a water bath at 40 to 70 °C for 6 to 18 h to obtain a uniform electrospray slurry;

[0050] The aqueous dispersant described in Step ① is one or both of polyvinylpyrrolidone and N-methylpyrrolidone;

[0051] The pore-forming agent described in Step ① is polyethersulfone or polytetrafluoroethylene;

[0052] The mass ratio of the mixed ceramic powder to the pore-forming agent described in Step ① is (2 to 5):1;

[0053] The mass ratio of the mixed ceramic powder to the aqueous dispersant described in Step ① is 1:(0.5 to 2);

[0054] ②. Electrospray granulation:

[0055] Load the electrospray slurry into an electrospray syringe with a positive voltage. The voltage at the tip of the needle tube is 10 to 30 kV, the needle size is 0.5 to 2 mm, the discharge rate is 0.5 to 2 mg / s, and the receiving container is deionized water to obtain a suspension;

[0056] ③. Microsphere post-treatment:

[0057] Filter the suspension, and then dry the solid matter at 60 to 120 °C for 3 to 24 h to obtain a dried spherical granulated powder; calcine the dried spherical granulated powder at 1000 to 1500 °C for 1 to 6 h to obtain a spherical porous electrospray granulation feed powder;

[0058] The spray granulation process described in Step 4 is completed according to the following steps:

[0059] Dissolve phenylacetic acid, polyvinyl alcohol, and mixed ceramic powder in deionized water at a mass ratio of 1:1:(3 - 6) to obtain a slurry with a solid content of 20 - 40%; then perform spray granulation at a hot air velocity of 0.3 - 0.6 m / s, a temperature of 100°C - 220°C, and a spray pump pressure of 1 - 5 MPa to obtain a spray granulation feed powder. Other steps are the same as those in Embodiments 1 to 8.

[0060] Specific Embodiment 10: The difference between this embodiment and one of Embodiments 1 to 9 is as follows: In Step 5, the parameters of the plasma spraying are as follows: the current is 500 A - 700 A, the main gas flow is 30 - 55 slpm, the auxiliary gas flow is 3 - 10 slpm, the carrier gas flow is 1 slpm - 5 slpm, and the powder feeding rate is 1 - 5 rpm; the thickness of the high-strength and tough / low thermal conductivity / anti-radiation penetration functional surface layer in Step 5 is 20 μm - 500 μm; the high-strength and tough / low thermal conductivity / anti-radiation penetration functional surface layer in Step 5 has a dispersed particle system structure, that is, micropores and functional dispersed phases are uniformly distributed in the matrix ceramic, where the equivalent radius of the micropores is 0.5 - 5 μm, the equivalent radius of the functional dispersed phase is 0.3 - 10 μm, the surface layer porosity is 5% - 20%, and the volume fraction of the micropores and the functional dispersed phase in the surface layer is 5 - 50%; the thermal conductivity of the high-strength and tough / low thermal conductivity / anti-thermal radiation penetration integrated thermal barrier ceramic coating in Step 5 is less than 1 W / (m·K), the bonding strength is greater than 25 MPa, the hardness is greater than 2.5 GPa, and the fracture toughness is greater than 2.5 MPa·m 1 / 2 , the infrared reflectivity in the 0.3 - 10 μm band is greater than 0.8, and the infrared transmittance is less than 0.15. Other steps are the same as those in Embodiments 1 to 9.

[0061] The following examples are used to verify the beneficial effects of the present invention:

[0062] Example 1: Y 3 NbO 7 -GdTaO 4 A preparation method for a high-strength and tough / low thermal conductivity / anti-thermal radiation penetration integrated thermal barrier ceramic coating is completed according to the following steps:

[0063] I. Substrate surface pretreatment:

[0064] First, remove the oxide film and grease on the substrate surface, then roughen the substrate surface, and finally perform thermal spraying preheating treatment on the substrate surface;

[0065] The substrate in Step I is a high-temperature nickel-based alloy (GH4061);

[0066] The method for removing the oxide film and grease on the substrate surface in Step I is as follows: First, polish the substrate with sandpaper, and then use anhydrous ethanol to remove the surface oil stain;

[0067] In Step 1, the method for roughening the surface of the substrate is as follows: under a pressure of 0.3 MPa, the substrate is sandblasted with 45# corundum sand to obtain the pre-treated substrate, and the surface roughness of the substrate is 2 μm;

[0068] In Step 1, the temperature for thermal spraying preheating is 800 °C;

[0069] II. Preparation of the bonding layer:

[0070] The bonding layer powder is sprayed onto the surface of the workpiece by means of an atmospheric plasma spraying process to obtain the substrate with the bonding layer;

[0071] The bonding layer powder described in Step 2 is NiCrAlY;

[0072] The atmospheric plasma spraying process described in Step 2 is as follows: the current is 580 A, the main gas flow is 40 slpm, the auxiliary gas flow is 3.5 slpm, the carrier gas flow is 3.2 slpm, and the powder feeding rate is 3 rpm;

[0073] In Step 2, the thickness of the bonding layer on the substrate with the bonding layer is 80 μm;

[0074] III. Preparation of the ceramic matrix phase component and the dispersed phase functional ceramic component:

[0075] The ceramic matrix phase component Y 3 NbO 7 and the dispersed phase functional ceramic component GdTaO 4 ;

[0076] In Step 3, Y 2 O 3 and Nb 2 O 5 react through solid-phase reaction to obtain Y 3 NbO 7 ; Gd 2 O 3 and Ta 2 O 5 react through solid-phase reaction to obtain GdTaO 4 ;

[0077] In Step 3, the refractive index n of GdTaO 4 is 2.1, and the refractive index n of Y 3 NbO 7 is 1.7; the thermal expansion coefficient of GdTaO 4 is 11.2×10 -6 K -1 , and the thermal expansion coefficient of the matrix ceramic Y 3 NbO 7 is 11×10 -6 K-1 ; The thermal conductivity of GdTaO 4 is 1.7 W / (m·K), and that of Y 3 NbO 7 is 1.5 W / (m·K); GdTaO 4 data is monoclinic system, and Y 3 NbO 7 belongs to cubic system, and there is no infinite solid solution effect between the two phases; GdTaO 4 has ferroelastic phase transition characteristics; GdTaO 4 has an original particle size of 1 μm, and the matrix ceramic Y 3 NbO 7 has an original particle size of 3 μm;

[0078] IV. Mixing and spherical granulation of functional ceramic powders:

[0079] Weigh the ceramic matrix component and the dispersed phase functional ceramic component in proportion, and then carry out powder mixing and spherical granulation treatment on the weighed ceramic matrix component and the dispersed phase functional ceramic component to obtain a spherical mixed powder feedstock;

[0080] The molar ratio of the ceramic matrix component and the dispersed phase functional ceramic component described in step IV is 5:1;

[0081] In step IV, powder mixing is carried out first and then spherical granulation treatment. The mixing process is as follows: Put the mixed powder, absolute ethanol and zirconia balls into a planetary ball mill tank in a mass ratio of 1:0.1:3, and ball mill for 6 h to 12 h at a rotation speed of 200 r / min to 400 r / min to obtain a slurry, and then dry the slurry at 60 °C to 120 °C for 3 h to 12 h to obtain mixed ceramic powder; The process of spherical granulation treatment is carried out by electrospray granulation, and specifically it is completed according to the following steps:

[0082] ①. Prepare electrospray slurry:

[0083] Disperse the mixed ceramic powder in an aqueous dispersant, then ultrasonicate for 50 min, add a pore-forming agent, and heat and stir in a water bath at 60 °C for 12 h to obtain a uniform electrospray slurry;

[0084] The aqueous dispersant described in step ① is N-methylpyrrolidone;

[0085] The pore-forming agent described in step ① is polyethersulfone;

[0086] The mass ratio of the mixed ceramic powder to the pore-forming agent described in step ① is 3:1;

[0087] The mass ratio of the mixed ceramic powder to the aqueous dispersant described in step ① is 1:1;

[0088] ②. Electrospray granulation:

[0089] Load the electrospray slurry into an electrospray syringe with a positive voltage. The voltage at the tip of the needle tube is 20 kV, the needle size is 0.5 mm, the discharge rate is 0.5 mg / s, and deionized water is selected as the receiving container to obtain a suspension;

[0090] ③. Post-treatment of microspheres:

[0091] Filter the suspension, and then dry the solid matter at 120 °C for 8 h to obtain dried spherical granulated powder; calcine the dried spherical granulated powder at 1200 °C for 6 h to obtain spherical porous electrospray granulated feed powder; the particle size of the spherical porous electrospray granulated feed powder is about 28 μm, and the porosity is 20%;

[0092] V. Preparation of a high-strength, tough, low-thermal-conductivity, and anti-radiation-penetration functional surface layer:

[0093] Adopt the method of plasma spraying to spray the spheroidized mixed powder feed onto the surface of the substrate with a bonding layer, and prepare a high-strength, tough, low-thermal-conductivity, and anti-radiation-penetration functional surface layer on the surface of the substrate to obtain Y 3 NbO 7 -GdTaO 4 A high-strength, tough, low-thermal-conductivity, and anti-thermal-radiation-penetration integrated thermal barrier ceramic coating.

[0094] The parameters of the plasma spraying described in step V are: current is 550 A, main gas flow is 45 slpm, auxiliary gas flow is 3.3 slpm, carrier gas flow is 3.2 slpm, and powder feeding rate is 3 rpm; the thickness of the high-strength, tough, low-thermal-conductivity, and anti-radiation-penetration functional surface layer described in step V is 220 μm; the high-strength, tough, low-thermal-conductivity, and anti-radiation-penetration functional surface layer described in step V has a dispersed particle system structure, that is, micropores and functional dispersed phases are uniformly distributed in the matrix ceramic, that is, composed of micropores with an average equivalent radius of 2 μm and GdTaO with an average equivalent radius of 5 μm 4 Dispersed in Y 3 NbO 7 Composition, the porosity of the coating is 11%, and the volume fraction of micropores and GdTaO 4 Occupying the coating is 27%;

[0095] The thermal conductivity of the high-strength, tough, low-thermal-conductivity, and anti-thermal-radiation-penetration integrated thermal barrier ceramic coating described in step V is 0.56 W / (m·K), the bonding strength with the substrate is 34 MPa, the hardness is 4 Gpa, and the fracture toughness is 3.5 MPa·m 1 / 2 、The infrared reflectivity in the 0.3 - 10 μm band is 0.88, and the infrared transmittance is less than 0.1.

[0096] Figure 2Morphology diagram of the spherical porous electrospray granulation feed powder prepared in Step 4 of Example 1;

[0097] From Figure 2 it can be seen that the spherical porous electrospray granulation feed powder prepared in Step 4 of Example 1 has a good spherical structure, with a size of 28 μm and a porous structure.

[0098] Figure 3 XRD pattern, where 1 is Y 3 NbO 7 , 2 is GdTaO 4 , and 3 is the spherical porous electrospray granulation feed powder prepared in Step 4 of Example 1;

[0099] From Figure 3 it can be seen that the original powder can be confirmed as Y 3 NbO 7 and GdTaO 4 . When the composite feed is thermally sprayed onto the surface of the nickel-based alloy, Y 3 NbO 7 and GdTaO 4 still exist as two phases, which proves that Y 3 NbO 7 and GdTaO 4 can exist in a multiphase structure and will not form a single phase by solid solution, providing conditions for optical scattering at the heterogeneous interface and improving the coating reflectivity;

[0100] Figure 4 SEM image of the surface of the high-strength, high-toughness / low-thermal-conductivity / anti-thermal-radiation-penetration integrated thermal barrier ceramic coating of Y 3 NbO 7 -GdTaO 4 prepared in Step 5 of Example 1;

[0101] From Figure 4 it can be seen that in Example 1, a composite ceramic coating structure with GdTaO 4 dispersion-distributed in Y 3 NbO 7 was successfully prepared.

[0102] Figure 5 Ferroelastic domain structure diagram of GdTaO 3 NbO 7 -GdTaO 4 in the high-strength, high-toughness / low-thermal-conductivity / anti-thermal-radiation-penetration integrated thermal barrier ceramic coating prepared in Step 5 of Example 1; 4 ;

[0103] From Figure 5 it can be seen that: GdTaO 4It has a remarkable ferroelastic domain structure, verifying that the second phase described in Step 3 of Example 1 has ferroelastic phase transition characteristics.

[0104] Figure 6 For Y prepared in Step 5 of Example 1 3 NbO 7 -GdTaO 4 Cross-sectional morphology of the high-strength and tough / low thermal conductivity / anti-thermal radiation penetration integrated thermal barrier ceramic coating;

[0105] From Figure 6 It can be seen that the thickness of the Y 3 NbO 7 -GdTaO 4 high-strength and tough / low thermal conductivity / anti-thermal radiation penetration integrated thermal barrier ceramic coating prepared in Step 5 of Example 1 is 220 μm, and the micropores inside the coating are randomly distributed.

[0106] Figure 7 Is the spectral reflectivity map of the coating. In the figure, 1 is Y 3 NbO 7 , 2 is the Y 3 NbO 7 -GdTaO 4 high-strength and tough / low thermal conductivity / anti-thermal radiation penetration integrated thermal barrier ceramic coating prepared in Step 5 of Example 1.

[0107] In this example, a Fourier spectrometer was used to test the spectral response characteristics of the Y 3 NbO 7 -GdTaO 4 high-strength and tough / low thermal conductivity / anti-thermal radiation penetration integrated thermal barrier ceramic coating prepared in Step 5 of this example. The measurement results show that the Y 3 NbO 7 -GdTaO 4 high-strength and tough / low thermal conductivity / anti-thermal radiation penetration integrated thermal barrier ceramic coating has a reflectivity of 0.88 in the 0.3 - 10 μm band, as Figure 7 shown.

[0108] In this example, an LFA457 laser thermal conductivity meter was used to measure the thermal conductivity of the Y 3 NbO 7 -GdTaO 4 high-strength and tough / low thermal conductivity / anti-thermal radiation penetration integrated thermal barrier ceramic coating prepared in Step 5 of this example. The results show that the thermal conductivity of the Y 3 NbO 7 -GdTaO 4 high-strength and tough / low thermal conductivity / anti-thermal radiation penetration integrated thermal barrier ceramic coating is 0.56 W / (m·K) at 1000 °C.

[0109] Y prepared in Step Five of Example 1 3 NbO 7 -GdTaO 4 The high-strength and tough / low thermal conductivity / anti-thermal radiation penetration integrated thermal barrier ceramic coating has good bonding strength with the substrate, and the bonding strength is 34 MPa. At the same time, the coating has good thermal shock resistance, and the number of thermal shock cycles at room temperature and 1200 °C is greater than 50 times, thus proving that Y prepared in Step Five of Example 1 of this example 3 NbO 7 -GdTaO 4 The high-strength and tough / low thermal conductivity / anti-thermal radiation penetration integrated thermal barrier ceramic coating has excellent thermal protection performance.

[0110] Example 2: YSZ-NdAlO 3 The preparation method of the high-strength and tough / low thermal conductivity / anti-thermal radiation penetration integrated thermal barrier ceramic coating is completed according to the following steps:

[0111] I. Substrate surface pretreatment:

[0112] First, remove the oxide film and grease on the substrate surface, then roughen the substrate surface, and finally perform thermal spraying preheating treatment on the substrate surface;

[0113] The substrate described in Step I is a SiC substrate;

[0114] The method for removing the oxide film and grease on the substrate surface in Step I is: first polish the substrate with sandpaper, and then remove the oil stain on the surface with anhydrous ethanol;

[0115] The method for roughening the substrate surface in Step I is: laser texturing treatment, and the process parameters are:

[0116] The laser power is 5 kW, the pulse frequency is 15 Hz, the spot size is 15 μm, and the roughness of the textured substrate surface is 3 μm;

[0117] The temperature of the thermal spraying preheating described in Step I is 900 °C;

[0118] II. Preparation of the bonding layer:

[0119] Spray the bonding layer powder onto the workpiece surface by atmospheric plasma spraying process to obtain a substrate with a bonding layer;

[0120] The bonding layer powder described in Step II is Hf-Si;

[0121] The atmospheric plasma spraying process described in Step II is: the current is 600 A, the main gas flow is 45 slpm, the auxiliary gas flow is 3.5 slpm, the carrier gas flow is 3.5 slpm, and the powder feeding rate is 2.8 rpm;

[0122] The thickness of the bonding layer on the substrate with the bonding layer described in Step 2 is 100 μm;

[0123] III. Preparation of ceramic matrix components and dispersed phase functional ceramic components:

[0124] The dispersed phase functional ceramic component NdAlO is prepared by a solid-state reaction method 3 , and the ceramic matrix component YSZ is selected;

[0125] In Step 3, Nd 2 O 3 and Al 2 O 3 are subjected to solid-state reaction to obtain NdAlO 3 ; YSZ is a commercial yttria-stabilized zirconia ceramic;

[0126] In Step 3, the refractive index n of NdAlO 3 is 1.95, and the refractive index n of YSZ is 2.15; the thermal expansion coefficient of NdAlO 3 is 10.3×10 -6 K -1 , the thermal expansion coefficient of YSZ is 10.9×10 -6 K -1 , the thermal conductivity of NdAlO 3 is 3.8 W / (m·K), the thermal conductivity of YSZ is 2.3 W / (m·K), NdAlO 3 is orthorhombic, YSZ belongs to the cubic system, and there is no infinite solid solution effect between the two phases; NdAlO 3 has ferroelastic phase transition characteristics; the original particle size of NdAlO 3 is 1.5 μm, and the original particle size of YSZ is 5 μm;

[0127] IV. Mixing and spherical granulation of functional ceramic powders:

[0128] Weigh the ceramic matrix components and dispersed phase functional ceramic components in proportion, then perform spherical granulation on the weighed ceramic matrix components and dispersed phase functional ceramic components, and then mix them to obtain a spherical composite powder feedstock;

[0129] In Step 4, the molar ratio of the ceramic matrix components to the dispersed phase functional ceramic components is 3:1;

[0130] In Step 4, the granulation method of the ceramic matrix components is electrospray granulation, and the granulation method of the dispersed phase functional ceramic components is spray drying granulation;

[0131] In Step 4, the granulation method of the ceramic matrix components is electrospray granulation, which is specifically completed according to the following steps:

[0132] ①. Preparation of electrospray slurry:

[0133] Dissolve YSZ powder and polyethersulfone pore former in N-methylpyrrolidone at a mass ratio of 4:1, ultrasonicate for 50 min, and stir in a water bath at 60 °C for 12 h to obtain a uniform electrospray slurry.

[0134] In step ①, the mass ratio of the YSZ powder to N-methylpyrrolidone is 1:1.2.

[0135] ②. Electrospray granulation:

[0136] Load the electrospray slurry into an electrospray syringe with a positive voltage. The voltage at the tip of the needle tube is 20 kV, the needle size is 0.76 mm, the discharge speed is 0.5 mg / s, and the receiving container is deionized water to obtain a suspension.

[0137] ③. Post-treatment of microspheres:

[0138] Filter the suspension, and then dry the solid matter at 100 °C for 12 h to obtain dry spherical granulated powder; calcine the dry spherical granulated powder at 1200 °C for 4 h to obtain spherical porous YSZ electrospray granulated feed powder; the particle size of the spherical porous YSZ electrospray granulated feed powder is about 50 μm, and the porosity is 18%.

[0139] The granulation method of the dispersed phase functional ceramic component NdAlO 3 is selected as spray drying granulation, and it is specifically completed according to the following steps:

[0140] Disperse phenylacetic acid, polyvinyl alcohol and NdAlO 3 ceramic powder in deionized water at a mass ratio of 1:1:4 to obtain a slurry, and the solid content in the slurry is 30%; spray granulate the slurry at a hot air speed of 0.5 m / s, a temperature of 160 °C and a spray pump pressure of 3 MPa to obtain spherical NdAlO 3 feed powder.

[0141] In step four, the mixing method of the spherical porous YSZ electrospray granulated feed powder and the spherical NdAlO 3 feed powder is selected as ordinary ball milling mixing, that is, weigh the spherical porous YSZ electrospray granulated feed powder and the spherical NdAlO 3 feed powder according to a mass ratio of 1:3, and then put ZrO 2 balls and the above-mentioned mixed feed into an ordinary ball milling tank at a ball-to-material ratio of 1:0.1, and ball mill at a rotation speed of 150 r / min for 3 h to obtain a spherical composite powder feed.

[0142] V. Preparation of a high-strength, tough, low-thermal-conductivity and radiation-resistant-penetration functional surface layer:

[0143] By using the method of plasma spraying, the spherical composite powder feedstock is sprayed onto the surface of the substrate with a bonding layer to prepare a functional surface layer with high strength and toughness / low thermal conductivity / anti-radiation penetration on the substrate surface, and YSZ-NdAlO 3 Integrated thermal barrier ceramic coating with high strength and toughness / low thermal conductivity / anti-thermal radiation penetration.

[0144] The parameters of the plasma spraying described in step five are: current is 600 A, main gas flow is 45 slpm, auxiliary gas flow is 3.5 slpm, carrier gas flow is 3.2 slpm, powder feeding rate is 3 rpm; the thickness of the functional surface layer with high strength and toughness / low thermal conductivity / anti-radiation penetration described in step five is 220 μm; the functional surface layer with high strength and toughness / low thermal conductivity / anti-radiation penetration described in step five has a dispersed particle system structure, that is, micropores and functional dispersed phases are uniformly distributed in the matrix ceramic, that is, composed of micropores with an average equivalent radius of 1.5 μm and NdAlO with an average equivalent radius of 3.5 μm 3 dispersedly distributed in YSZ, the porosity of the coating is 9%, and the volume fractions of micropores and NdAlO 3 in the coating are 24%;

[0145] The YSZ-NdAlO 3 Integrated thermal barrier ceramic coating with high strength and toughness / low thermal conductivity / anti-thermal radiation penetration has a thermal conductivity of 0.85 W / (m·K), a bonding strength with the substrate of 23 Mpa, a hardness of 2.6 Gpa, a fracture toughness of 3.2 MPa·m 1 / 2 、and an infrared reflectivity in the range of 0.3 - 10 μm is 0.87, and the infrared transmittance is less than 0.1. In this example, a Fourier spectrometer is used to test the spectral response characteristics of the YSZ-NdAlO 3 Integrated thermal barrier ceramic coating with high strength and toughness / low thermal conductivity / anti-thermal radiation penetration prepared in step five of this example. The measurement results show that the YSZ-NdAlO 3 Integrated thermal barrier ceramic coating with high strength and toughness / low thermal conductivity / anti-thermal radiation penetration prepared in step five of this example has a reflectivity of 0.87 in the range of 0.3 - 10 μm.

[0146] In this example, an LFA457 laser thermal conductivity meter is used to measure the thermal conductivity of the YSZ-NdAlO 3 Integrated thermal barrier ceramic coating with high strength and toughness / low thermal conductivity / anti-thermal radiation penetration prepared in step five of this example. The results show that the thermal conductivity of the YSZ-NdAlO 3 Integrated thermal barrier ceramic coating with high strength and toughness / low thermal conductivity / anti-thermal radiation penetration prepared in step five is 0.85 W / (m·K) at 1000 °C.

[0147] The YSZ-NdAlO prepared in step five of Example 2 3The high-strength, high-toughness / low-thermal-conductivity / anti-thermal-radiation-penetration integrated thermal barrier ceramic coating has good bonding strength with the substrate, and the bonding strength is 23 MPa. At the same time, the coating has good thermal shock resistance, and the number of thermal shock cycles at room temperature and 1200 °C is greater than 50 times, thus proving that the YSZ-NdAlO prepared in this embodiment 3 The high-strength, high-toughness / low-thermal-conductivity / anti-thermal-radiation-penetration integrated thermal barrier ceramic coating has excellent thermal protection performance.

[0148] Comparative Example 1: Al 2 O 3 doped with Y 3 NbO 7 The preparation method of the ceramic coating is completed according to the following steps:

[0149] I. Substrate surface pretreatment:

[0150] First, remove the oxide film and grease on the substrate surface, then roughen the substrate surface, and finally perform thermal spraying preheating treatment on the substrate surface;

[0151] The substrate in Step I is a high-temperature nickel-based alloy (GH4061); the method for removing the oxide film and grease on the substrate surface in Step I is: first, polish the substrate with sandpaper, and then use anhydrous ethanol to remove the oil stain on the surface;

[0152] The method for roughening the substrate surface in Step I is: under a pressure of 0.3 MPa, blast the substrate with 45# corundum sand to obtain the pretreated substrate, and the surface roughness of the substrate is 2 μm;

[0153] The temperature of the thermal spraying preheating in Step I is 800 °C;

[0154] II. Preparation of the bonding layer:

[0155] Spray the bonding layer powder onto the workpiece surface by using the atmospheric plasma spraying process to obtain the substrate with the bonding layer;

[0156] The bonding layer powder in Step II is NiCrAlY;

[0157] The atmospheric plasma spraying process in Step II is: the current is 580 A, the main gas flow is 40 slpm, the auxiliary gas flow is 3.5 slpm, the carrier gas flow is 3.2 slpm, and the powder feeding rate is 3 rpm;

[0158] The thickness of the bonding layer on the substrate with the bonding layer in Step II is 80 μm;

[0159] III. Preparation of the ceramic matrix phase component and the dispersed phase functional ceramic component:

[0160] Prepare the ceramic matrix component Y by solid-phase reaction 3 NbO 7 , and select Al 2 O 3 ;

[0161] In step three, Y 2 O 3 and Nb 2 O 5 undergo solid-phase reaction to obtain Y 3 NbO 7 ; Use commercial Al 2 O 3 ;

[0162] The refractive index n of the Al 2 O 3 described in step three is 1.75, and the refractive index n of Y 3 NbO 7 is 1.7 (the difference in dielectric functions between the two is too small); The thermal expansion coefficient of Al 2 O 3 is 7.45×10 -6 K -1 , and the thermal expansion coefficient of Y 3 NbO 7 is 11×10 -6 K -1 (the expansion coefficients of the two do not match); The thermal conductivity of Al 2 O 3 is 7.8 W / (m·K), and the thermal conductivity of Y 3 NbO 7 is 1.5 W / (m·K) (the thermal conductivity of Al 2 O 3 is too large); Al 2 O 3 belongs to the hexagonal crystal system, and Y 3 NbO 7 belongs to the cubic crystal system, and there is no infinite solid solution effect between the two phases; Al 2 O 3 does not have ferroelastic phase transition characteristics (it cannot achieve ferroelastic toughening effect); The original particle size of Al 2 O 3 is 1 μm, and the original particle size of Y 3 NbO 7 is 3 μm;

[0163] IV. Mixing and spherical granulation of functional ceramic powder:

[0164] Weigh the ceramic matrix phase components and the dispersed phase functional ceramic components proportionally, and then mix the weighed ceramic matrix phase components and the dispersed phase functional ceramic components for powder mixing and spherical granulation treatment to obtain a spherical mixed powder feedstock;

[0165] The molar ratio of the ceramic matrix phase components and the dispersed phase functional ceramic components described in step four is 5:1;

[0166] In step four, powder mixing is carried out first and then spherical granulation treatment. The mixing process is as follows: Put the mixed powder, anhydrous ethanol, and zirconia balls into a planetary ball mill tank according to a mass ratio of 1:0.1:3, and ball mill for 8 hours at a rotation speed of 300 r / min to obtain a slurry; Dry the slurry at 100 °C for 6 hours to obtain the ball-milled mixed powder;

[0167] The ball-milled mixed powder is subjected to electrospray granulation, which is specifically completed according to the following steps:

[0168] ①. Prepare the electrospray slurry:

[0169] Dissolve the ball-milled mixed powder and the polyethersulfone pore-forming agent in N-methylpyrrolidone according to a mass ratio of 3:1, ultrasonicate for 50 minutes, and heat and stir in a water bath at 60 °C for 12 hours to obtain a uniform electrospray slurry;

[0170] The mass ratio of the ball-milled mixed powder to N-methylpyrrolidone described in step ① is 1:1;

[0171] ②. Electrospray granulation:

[0172] Load the electrospray slurry into an electrospray syringe with a positive voltage. The voltage at the tip of the needle tube is 20 kV, the needle size is 0.5 mm, the discharge speed is 0.5 mg / s, and the receiving container is deionized water to obtain a suspension;

[0173] ③. Microsphere post-treatment:

[0174] Filter the suspension, and then dry the solid matter at 120 °C for 8 hours to obtain a dried spherical granulated powder; Calcinate the dried spherical granulated powder at 1200 °C for 6 hours to obtain a spherical porous electrospray granulated feedstock powder; The particle size of the spherical porous electrospray granulated feedstock powder is about 26 μm, and the porosity is 19%;

[0175] V. Prepare a high-strength and tough / low thermal conductivity / radiation penetration-resistant functional surface layer:

[0176] Using the method of plasma spraying, spray the spherical mixed powder feedstock onto the surface of the substrate with an adhesive layer to obtain an Al 2 O 3 doped with Y 3 NbO 7 ceramic coating.

[0177] The process of plasma spraying described in step five is as follows: the current is 550 A, the main gas flow is 45 slpm, the auxiliary gas flow is 3.3 slpm, the carrier gas flow is 3.2 slpm, and the powder feeding rate is 3.5 rpm; the thickness of the surface layer described in step two is 220 μm;

[0178] The Al 2 O 3 doped with Y 3 NbO 7 ceramic coating consists of micropores with an average equivalent radius of 1.8 μm and Al 2 O 3 dispersed in Y 3 NbO 7 The porosity of the coating is 10%, and the volume fraction of the micropores and Al 2 O 3 in the coating is 25%;

[0179] In this embodiment, a Fourier spectrometer is used to test the spectral response characteristics of the Al 2 O 3 doped with Y 3 NbO 7 ceramic coating prepared in step five of this embodiment. The measurement results show that the Al 2 O 3 doped with Y 3 NbO 7 ceramic coating prepared in step five of this embodiment has a reflectivity of 0.65 in the wavelength range of 0.5 - 10 μm.

[0180] In this embodiment, an LFA457 laser thermal conductivity meter is used to measure the thermal conductivity of the Al 2 O 3 doped with Y 3 NbO 7 ceramic coating prepared in step five of this embodiment. The results show that the thermal conductivity of the Al 2 O 3 doped with Y 3 NbO 7 ceramic coating prepared in step five is 1.54 W / (m·K) at 1000 °C.

[0181] The Al 2 O 3 doped with Y 3 NbO 7 ceramic coating prepared in step five has a thermal conductivity of 1.5 W / (m·K), a bonding strength with the substrate of 25 MPa, a hardness of 1.8 GPa, and a fracture toughness of 2 MPa·m 1 / 2, the infrared reflectivity in the wavelength band of 0.3 to 10 μm is 0.65, and the infrared transmittance is 0.32.

Claims

1. A preparation method of an integrated thermal barrier ceramic coating with high strength and toughness / low thermal conductivity / anti-thermal radiation penetration, characterized in that this preparation method is completed according to the following steps: I. Substrate surface pretreatment: First, remove the oxide film and grease on the substrate surface, then roughen the substrate surface, and finally perform thermal spraying preheating treatment on the substrate surface; II. Preparation of the bonding layer: Adopt the process of atmospheric plasma spraying to spray the bonding layer powder onto the workpiece surface to obtain a substrate with a bonding layer; The bonding layer powder described in step II needs to be selected according to the type of substrate. When the substrate is a metal-based material, the bonding layer powder selects MCrAlY, where M is Ni, Co or NiCo; when the substrate is a ceramic-based material treated by laser texturing, the bonding layer powder selects RE-Si, where RE is a rare earth element, and the rare earth element is Hf or Y; III. Preparation of ceramic matrix phase components and dispersed phase functional ceramic components: Adopt the sol-gel or solid-phase reaction method to prepare ceramic matrix phase components and dispersed phase functional ceramic components; The absolute value of the difference in the thermal expansion coefficients between the ceramic matrix component and the dispersed-phase functional ceramic component described in Step 3 is less than 1.5×10 -6 K -1 ; The ceramic matrix phase components and dispersed phase functional ceramic components described in step III belong to different crystal systems, and there is no infinite solid solution effect between the two phases; The dielectric function of the ceramic matrix phase component and the dispersed phase functional ceramic component described in step three N has a large difference, that is, the absolute value of the difference in refractive index between the ceramic matrix phase component and the dispersed phase functional ceramic component n needs to be greater than 0.3, or the absolute value of the difference in extinction coefficient between the ceramic matrix phase component and the dispersed phase functional ceramic component k needs to be greater than 1; the dielectric function N = n +i k , where n is the refractive index of the ceramic, and i is the imaginary unit symbol; k is the extinction coefficient of the ceramic; The thermal conductivity of the ceramic matrix phase components described in step III is less than 3 W / (m·K); the ceramic matrix phase components are yttria-stabilized zirconia or rare earth niobates, zirconates or hafniates with a fluorite or pyrochlore crystal structure; the dispersed phase functional ceramic components described in step III are ceramic components with high-temperature ferroelastic phase transformation characteristics and low thermal conductivity less than 5 W / (m·K); the dispersed phase functional ceramic components are rare earth tantalates or aluminates; IV. Mixing and spherical granulation of functional ceramic powders: Weigh the ceramic matrix phase components and dispersed phase functional ceramic components according to the ratio, and then perform powder mixing and spherical granulation treatment on the weighed ceramic matrix phase components and dispersed phase functional ceramic components to obtain spherical porous composite feedstock; The molar ratio of the ceramic matrix phase components and dispersed phase functional ceramic components described in step IV is (3~20):1; V. Preparation of a functional surface layer with high strength and toughness / low thermal conductivity / anti-radiation penetration: Adopt the plasma spraying method to spray the spherical composite feedstock onto the surface of the substrate with a bonding layer, and prepare a functional surface layer with high strength and toughness / low thermal conductivity / anti-radiation penetration on the substrate surface to obtain an integrated thermal barrier ceramic coating with high strength and toughness / low thermal conductivity / anti-thermal radiation penetration; The functional surface layer with high strength and toughness / low thermal conductivity / anti-radiation penetration described in step V has a dispersed particle system structure, that is, micropores and functional dispersed phases are uniformly distributed in the matrix ceramic, where the equivalent radius of the micropores is 0.5~5 μm, the equivalent radius of the functional dispersed phase is 0.3~10 μm, the porosity of the surface layer is 5%~20%, and the volume fraction of the micropores and functional dispersed phases in the surface layer is 5~50%.

2. According to the preparation method of an integrated thermal barrier ceramic coating with high strength and toughness / low thermal conductivity / anti-thermal radiation penetration described in claim 1, characterized in that The substrate described in Step 1 is a metal matrix material or a ceramic matrix material; the metal matrix material is a titanium aluminum alloy, a nickel-based alloy or a niobium-based alloy; the ceramic matrix material is C / C, SiC / SiC, C / SiC or SiC / Si 3 N 4 ; the method for removing the oxide film and grease on the surface of the substrate in Step 1 is to polish the substrate with sandpaper to remove the oxide film, and then use one or more of the solvent cleaning method, steam cleaning method, alkali cleaning method and heating degreasing method to remove the grease on the substrate; the method for roughening the surface of the substrate in Step 1 is sandblasting or laser texturing. Sandblasting is used when the substrate is a metal matrix material, and laser texturing is used when the substrate is a ceramic matrix material; the parameters of the sandblasting are: the sand grain size is 15-50 mesh, and the sandblasting pressure is 0.3-0.7 MPa; the laser texturing parameters are: the laser power is 1-8 kW, the pulse frequency is 10-20 Hz, the spot size is 10-100 μm, and the roughness of the textured substrate surface is 1-5 μm; the temperature of the thermal spraying preheating in Step 1 is 600-900 °C.

3. According to the preparation method of an integrated thermal barrier ceramic coating with high strength and toughness / low thermal conductivity / anti-thermal radiation penetration described in claim 1, characterized in that The process of atmospheric plasma spraying described in Step 2 is as follows: the current is 600A - 650A, the main gas flow is 40 - 50 slpm, the auxiliary gas flow is 3 - 10 slpm, the carrier gas flow is 1 slpm - 5 slpm, and the rotation speed of powder feeding is 1 - 3 rpm; the thickness of the bonding layer on the substrate with a bonding layer described in Step 2 is 20μm - 200μm.

4. A method for preparing a high-strength and tough / low thermal conductivity / anti-thermal radiation penetration integrated thermal barrier ceramic coating according to claim 1, characterized in that the particle size of the powder for preparing the ceramic matrix component in Step 3 is 1 - 10μm, and the particle size of the powder for preparing the dispersed phase functional ceramic component is less than 3μm.

5. A method for preparing a high-strength and tough / low thermal conductivity / anti-thermal radiation penetration integrated thermal barrier ceramic coating according to claim 1, characterized in that; the process of powder mixing and spherical granulation treatment in Step 4 does not distinguish the order; when powder mixing is carried out first and then spherical granulation treatment, the mixing process is as follows: a certain proportion of the original powders of the matrix phase and the dispersed functional phase, anhydrous ethanol, and zirconia balls are put into a planetary ball mill tank machine according to a mass ratio of 1:0.1:3, and ball milled at a rotation speed of 200r / min - 400r / min for 6h - 12h to obtain an original powder mixed slurry, and then the slurry is dried at 60℃ - 120℃ for 3h - 12h to obtain the original ceramic powder with the matrix phase and the dispersed phase uniformly mixed, and then the mixed original powder is subjected to spherical granulation treatment to obtain a spherical porous composite feed; when spherical granulation treatment is carried out first and then mixing, the mixing process of the granulated powder is as follows: by using the ordinary dry ball milling method, the spherical porous matrix phase and the spherical dispersed phase powder are put into an ordinary ball mill tank according to a ratio, and ball milled for 3h under the conditions of a ball-to-material ratio of 1:0.1 and a rotation speed of 150r / min to obtain a spherical porous composite feed.

6. A method for preparing a high-strength and tough / low thermal conductivity / anti-thermal radiation penetration integrated thermal barrier ceramic coating according to claim 1, characterized in that the method of spherical granulation in Step 4 is one or both of electrospray granulation and spray granulation; the particle size of the spherical porous composite feed described in Step 4 is 1 - 100μm.

7. A method for preparing a high-strength and tough / low thermal conductivity / anti-thermal radiation penetration integrated thermal barrier ceramic coating according to claim 6, characterized in that the process of electrospray granulation described in Step 4 is completed according to the following steps: ①. Preparation of electrospray slurry: Disperse the mixed ceramic powder in an aqueous dispersant, then ultrasonic for 30 - 100 min, add a pore-forming agent, and heat and stir in a water bath at 40 - 70℃ for 6 - 18h to obtain a uniform electrospray slurry; the aqueous dispersant described in Step ① is one or both of polyvinylpyrrolidone and N-methylpyrrolidone; the pore-forming agent described in Step ① is polyethersulfone or polytetrafluoroethylene; the mass ratio of the mixed ceramic powder to the pore-forming agent in Step ① is (2 - 5):1; the mass ratio of the mixed ceramic powder to the aqueous dispersant in Step ① is 1:(0.5 - 2); ②. Electrospray granulation: Load the electrospray slurry into an electrospray syringe with a positive voltage. The voltage at the tip of the needle tube is 10 - 30 kV, the needle size is 0.5 - 2 mm, the discharging speed is 0.5 - 2 mg / s, and the receiving container is deionized water to obtain a suspension; ③. Post-treatment of microspheres: Filter the suspension, and then dry the solid material at 60 - 120 °C for 3 - 24 h to obtain a dried spherical granulated powder; calcine the dried spherical granulated powder at 1000 - 1500 °C for 1 - 6 h to obtain a spherical porous electrospray granulated feed powder; The spray granulation process described in step four is completed according to the following steps: Disperse phenylacetic acid, polyvinyl alcohol, and mixed ceramic powder in deionized water in a mass ratio of 1:1:(3 - 6) to obtain a slurry with a solid content of 20 - 40% in the slurry; then carry out spray granulation at a hot air speed of 0.3 - 0.6 m / s, a temperature of 100 °C - 220 °C, and a spray pump pressure of 1 - 5 MPa to obtain a spray granulated feed powder.

8. According to the method for preparing a high-strength and tough / low thermal conductivity / anti-thermal radiation penetration integrated thermal barrier ceramic coating according to claim 1, characterized in that The parameters of the plasma spraying described in step five are as follows: the current is 500 A to 700 A, the main gas flow is 30 to 55 slpm, the auxiliary gas flow is 3 to 10 slpm, the carrier gas flow is 1 slpm to 5 slpm, and the rotational speed of powder feeding is 1 to 5 rpm; the thickness of the high-strength and tough / low thermal conductivity / anti-radiation penetration functional surface layer described in step five is 20 μm to 500 μm; the thermal conductivity of the high-strength and tough / low thermal conductivity / anti-thermal radiation penetration integrated thermal barrier ceramic coating described in step five is less than 1 W / (m·K), the bonding strength is greater than 25 MPa, the hardness is greater than 2.5 GPa, and the fracture toughness is greater than 2.5 MPa·m 1 / 2 and the infrared reflectivity in the 0.3 to 10 μm band is greater than 0.8, and the infrared transmittance is less than 0.15.

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