CN116377373A - A preparation method of high strength and toughness/low thermal conductivity/anti-thermal radiation penetration integrated thermal barrier ceramic coating - Google Patents

Abstract

A preparation method of a high-strength and high-toughness/low-heat-conductivity/heat-radiation-penetration-resistant integrated thermal barrier ceramic coating belongs to the technical field of thermal barrier coating materials. The invention aims to solve the problems that the thermal-radiation-resistant penetrating thermal barrier coating material prepared by the existing method has expensive precious metal second phase, and the thermal expansion coefficient between the metal doped second phase and the ceramic matrix is very different, so that the thermal expansion of the material is matched and fails at high temperature, the metal doped second phase has high thermal conductivity, the thermal conductivity of the composite material is increased, the thermal protection effect of the composite material under high-temperature service is reduced, and the hidden trouble that interface failure is easy to occur in the coating of a multilayer structure is solved. The method comprises the following steps: 1. pretreating the surface of a substrate; 2. preparing a bonding layer; 3. preparing a ceramic-based phase component and a disperse phase functional ceramic component; 4. mixing and granulating in a ball shape; 5. and preparing a functional surface layer. The invention can obtain the high-strength and high-toughness/low-heat-conductivity/heat-radiation-penetration-resistant integrated thermal barrier ceramic coating.

Description

Preparation of an integrated thermal barrier ceramic coating with high strength and toughness/low thermal conductivity/anti-thermal radiation penetration preparation method

technical field

The invention belongs to the technical field of thermal barrier coating materials, and in particular relates to a preparation method of an integrated thermal barrier ceramic coating with high strength and toughness/low thermal conductivity/anti-thermal radiation penetration.

Background technique

Thermal barrier coating is a key technology to protect the stable operation of turbine hot-end components and develop high thrust-to-weight ratio turbine engines and high-efficiency heavy-duty gas turbines. At present, the 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 niobate, hafnate, tannate and zirconate A series of high-temperature-resistant and low-thermal-conductivity oxide ceramic coating material systems such as salt; however, a key common bottleneck problem that restricts the application of the above-mentioned oxide systems in high-temperature gas environments is: the infrared transmittance of oxide thermal barrier ceramics such as niobate High (transmittance>0.5), poor high temperature heat radiation shielding performance. With the gas temperature > 1200°C, the heat flux density in the main radiation band (0.3-10μm) of the gas will reach more than 2300000W·m ^-2 , at this time, the thermal radiation penetration increase of the coating will cause a strong thermal shock to the substrate, only Having a low thermal conductivity can no longer meet the urgent needs of a new generation of ultra-high temperature turbine systems. At present, the research on high-temperature thermal radiation shielding of thermal barrier ceramic coatings is in its infancy and is very scarce.

At the end of 2022, a Chinese patent (CN 115233069 A) disclosed a composite ceramic material in which platinum microsheets 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, Chinese patent (CN 115010492 A) similarly disclosed a kind of noble metal nanoparticles uniformly dispersed in the ceramic matrix to reduce the infrared transmittance of the ceramic. However, the proposed structural design is limited to the design and preparation of ceramic bulk materials, and the second noble metal phase is not only expensive but also has the following series of problems. (1) The coefficient of thermal expansion between the metal-doped second phase and the ceramic base phase is very different, so it is easy to cause the thermal expansion matching failure of the material at high temperature; (2) The metal-doped second phase has high thermal conductivity, which will make the The thermal conductivity of the composite material increases, which reduces its thermal protection effect under high temperature service. In addition, there are some potential problems in improving the reflectivity and anti-radiation penetration of the coating by _{the multi} -layer structure. The spectral reflectance reaches 0.8, but it is prone to hidden dangers of interface failure. Therefore, there is an urgent need to develop an integrated thermal barrier ceramic coating system with strong toughness/low thermal conductivity/anti-thermal radiation penetration and its preparation method.

Contents of the invention

The purpose of the present invention is to solve the problem that the thermal radiation penetration resistance thermal barrier coating material prepared by the existing method has a noble metal second phase, which is not only expensive, but also has a large difference in thermal expansion coefficient between the metal-doped second phase and the ceramic base phase, resulting in material The thermal expansion matching at high temperature fails, and the metal-doped second phase has high thermal conductivity, which will increase the thermal conductivity of the composite material, reducing its thermal protection effect under high temperature service and the coating of the multilayer structure The problem of hidden danger of interface failure is prone to occur, and a preparation method of a high-strength/low thermal conductivity/thermal radiation penetration-resistant integrated thermal barrier ceramic coating is provided.

A method for preparing an integrated thermal barrier ceramic coating with high strength and toughness/low thermal conductivity/anti-thermal radiation penetration is completed according to the following steps:

1. Substrate surface pretreatment:

First remove the oxide film and grease on the surface of the substrate, then roughen the surface of the substrate, and finally perform thermal spraying preheating on the surface of the substrate;

2. Prepare the bonding layer:

The adhesive layer powder is sprayed onto the surface of the workpiece by the atmospheric plasma spraying process to obtain a substrate with an adhesive layer;

3. Preparation of ceramic base phase components and dispersed phase functional ceramic components:

Preparation of ceramic base phase components and dispersed phase functional ceramic components by means of sol-gel or solid phase reaction;

4. Mixing and spherical granulation of functional ceramic powder:

Weigh the ceramic base phase components and dispersed phase functional ceramic components in proportion, and then carry out powder mixing and spherical granulation treatment on the weighed ceramic base phase components and dispersed phase functional ceramic components to obtain spherical compound feeding;

5. Preparation of functional surface layer with high strength and toughness/low thermal conductivity/radiation penetration resistance:

Using the method of plasma spraying, the spheroidized compound feed is sprayed on the surface of the substrate with a bonding layer, and a functional surface layer with high strength, low thermal conductivity, and anti-radiation penetration is prepared on the surface of the substrate to obtain high strength, toughness, and low heat. Conductive/anti-thermal radiation penetration integrated thermal barrier ceramic coating.

Principle of the present invention:

The present invention designs and prepares a composite coating in which micropores and functional disperse phases are distributed on the thermal barrier ceramics in the base phase by means of electrospray or spray granulation-thermal spray; wherein a certain amount of pore-forming agent is introduced into the process of electrospray and spray granulation to obtain Porous feed, which in turn introduces micropores in the coating; large dielectric function differences between the second phase and the base ceramic through micropores (air), scattering, and the second phase by controlling the size of the dispersed phase (micropores) Between 0.3 and 10 μm, the volume fraction is between 5 and 50%, which can enable strong optical backscattering between it and the base phase interface. When the thickness of the coating is between 20 and 500 μm, the coating is between 0.3 and 10 μm The infrared reflectance of the band is greater than 0.8, and the infrared transmittance is less than 0.15; the difference in thermal expansion coefficient between the dispersed phase functional ceramic components and the ceramic base phase components is less than 1.5×10 ^-6 K ^-1 , making the dispersed phase functional ceramic components It has a good thermal expansion matching with the interface of the ceramic base phase component, which can avoid interface damage and failure caused by thermal shock at high and low temperatures; the dispersed phase functional ceramic component has high temperature ferroelastic phase transition characteristics, which can play a role in phase change and toughening. Finally, the thermal conductivity of the ceramic base phase components is less than 3W/(m·K), and the thermal conductivity of the dispersed phase functional ceramic components is less than 5W/(m·K). Together with the effect of micropores, the coating can be guaranteed The overall thermal conductivity is less than 1W/(m·K).

Advantages of the present invention:

1. Compared with the existing precious metal-ceramic composite system, the high-strength/low thermal conductivity/thermal radiation penetration-resistant integrated thermal barrier ceramic coating prepared by the present invention breaks through the high cost of precious metals, high thermal conductivity, and The poor matching of the thermal expansion coefficient of the matrix ceramic phase leads to the decline of thermal protection performance and the failure of the high-temperature interface; compared with the existing multi-layer structure coating scheme, its particle-dispersed coating structure system is not only simpler to prepare but also a breakthrough. The hidden danger of multi-interface failure under thermal stress;

2. The present invention is low in cost and simple in operation. The low thermal conductivity and anti-radiation penetration of the material can be realized by thermal spraying process. The material has good structure, good thermal expansion matching, strong stability and high environmental adaptability, so that the present invention The provided integrated thermal barrier ceramic coating with high strength and toughness/low thermal conductivity/anti-thermal radiation penetration has a good application prospect;

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

Description of drawings

Figure 1 is a schematic structural view of the microporous and functional disperse phases of the present invention distributed in the low thermal conductivity base phase to form an integrated thermal barrier ceramic coating with high strength and toughness/low thermal conductivity/anti-thermal radiation penetration;

Fig. 2 is the morphology diagram of the spherical porous electrospray granulation feeding powder prepared in step 4 of embodiment 1;

Figure 3 is the XRD pattern, in which 1 is Y ₃ NbO ₇ , 2 is GdTaO ₄ , and 3 is the Y ₃ NbO ₇ -GdTaO ₄ high strength and toughness/low thermal conductivity/thermal radiation penetration resistance integrated thermal barrier ceramic coating;

Fig. 4 is the SEM image of the surface of Y ₃ NbO ₇ -GdTaO ₄ high toughness/low thermal conductivity/anti-thermal radiation penetration integrated thermal barrier ceramic coating prepared in Step 5 of Example 1;

Fig. 5 is a ferroelastic domain structure diagram of GdTaO ₄ in the Y ₃ NbO ₇ -GdTaO ₄ high toughness/low thermal conductivity/thermal radiation penetration resistance integrated thermal barrier ceramic coating prepared in step 5 of Example 1;

Fig. 6 is the cross-sectional morphology of the Y ₃ NbO ₇ -GdTaO ₄ high-strength/low thermal conductivity/anti-thermal radiation penetration integrated thermal barrier ceramic coating prepared in Step 5 of Example 1;

Figure 7 is the spectral reflectance spectrum of the coating, in which 1 is Y ₃ NbO ₇ , and 2 is the Y ₃ NbO ₇ -GdTaO ₄ high-strength/low thermal conductivity/anti-thermal radiation penetration integrated heat treatment prepared in Step 5 of Example 1. barrier ceramic coating.

Detailed ways

Specific Embodiment 1: In this embodiment, a method for preparing a high-strength/low thermal conductivity/anti-thermal radiation penetration integrated thermal barrier ceramic coating is completed according to the following steps:

1. Substrate surface pretreatment:

First remove the oxide film and grease on the surface of the substrate, then roughen the surface of the substrate, and finally perform thermal spraying preheating on the surface of the substrate;

2. Prepare the bonding layer:

The adhesive layer powder is sprayed onto the surface of the workpiece by the atmospheric plasma spraying process to obtain a substrate with an adhesive layer;

3. Preparation of ceramic base phase components and dispersed phase functional ceramic components:

Preparation of ceramic base phase components and dispersed phase functional ceramic components by means of sol-gel or solid phase reaction;

4. Mixing and spherical granulation of functional ceramic powder:

Weigh the ceramic base phase components and dispersed phase functional ceramic components in proportion, and then carry out powder mixing and spherical granulation treatment on the weighed ceramic base phase components and dispersed phase functional ceramic components to obtain spherical compound feeding;

5. Preparation of functional surface layer with high strength and toughness/low thermal conductivity/radiation penetration resistance:

Using the method of plasma spraying, the spheroidized compound feed is sprayed on the surface of the substrate with a bonding layer, and a functional surface layer with high strength, low thermal conductivity, and anti-radiation penetration is prepared on the surface of the substrate to obtain high strength, toughness, and low heat. Conductive/anti-thermal radiation penetration integrated thermal barrier ceramic coating.

Embodiment 2: The difference between this embodiment and Embodiment 1 is: the substrate described in step 1 is a metal-based material or a ceramic-based material; the metal-based material is titanium-aluminum alloy, nickel-based alloy or niobium-based alloy; the ceramic-based 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 use sandpaper to remove the substrate by grinding Then use one or more of solvent cleaning method, steam cleaning method, alkali cleaning method and heating degreasing method to remove the substrate grease; the method of roughening the substrate surface in step 1 is sandblasting or laser roughening. When the substrate is a metal-based material, sand blasting is used, and when the substrate is a ceramic-based material, laser texturing is used; the parameters of the sand blasting treatment are: the sand particle size is 15 to 50, and the sand blasting pressure is 0.3 to 50. 0.7MPa; the laser texturing parameters are as follows: the laser power is 1-8kW, the pulse frequency is 10-20Hz, the spot size is 10-100μm, and the roughness of the obtained textured substrate surface is 1-5μm; The thermal spraying preheating temperature is 600-900°C. Other steps are the same as in the first embodiment.

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

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

Embodiment 5: The difference between this embodiment and Embodiments 1 to 4 is that the absolute value of the difference between the thermal expansion coefficients of the ceramic base phase components and the dispersed phase functional ceramic components described in step 3 is less than 1.5×10 ^-6 K ^-1 ; the thermal conductivity of the ceramic base phase component described in step 3 is less than 3W/(m K); the ceramic base phase component is yttria stabilized zirconia (YSZ) or has a fluorescent Rare earth niobate (RE ₃ NbO ₇ ), zirconate (RE ₃ Zr ₂ O ₇ ) or hafnate (RE ₃ Zr ₂ O ₇ ) with crystal structure of pyrochlore or pyrochlore; the dispersion described in step three The phase-functional ceramic component is a ceramic component with high-temperature ferroelastic phase transition characteristics and low thermal conductivity of less than 5W/(m·K); the dispersed-phase functional ceramic component is rare earth tannate or aluminate. Other steps are the same as those in Embodiments 1 to 4.

Embodiment 6: The difference between this embodiment and Embodiments 1 to 5 is that the ceramic base phase components and the dispersed phase functional ceramic components described in step 3 belong to different crystal systems, and there is no infinite solid between the two phases. Dissolution effect; in step 3, the powder particle size of the ceramic base phase component 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 Embodiments 1 to 5.

Embodiment 7: The difference between this embodiment and Embodiments 1 to 6 is that the molar ratio of the ceramic base phase components and the dispersed phase functional ceramic components described in step 4 is (3-20):1; The process of powder mixing and spheroidizing granulation treatment described in step 4 does not distinguish the sequence; when the powder is mixed first and then spheroidizing granulation treatment, the mixing process is as follows: mix a certain proportion of base phase and The original powder of the dispersed functional phase, absolute ethanol and zirconia balls are put into the planetary ball mill at a mass ratio of 1:0.1:3, and ball milled at a speed of 200r/min~400r/min for 6h~12h to obtain the original powder mixed slurry Then dry the slurry at 60°C-120°C for 3h-12h to obtain the original ceramic powder uniformly mixed with the base phase and the dispersed phase, and then carry out spheroidization and granulation treatment on the mixed original powder; When remixing after granulation treatment, the mixing process of granulated powder is as follows: adopt ordinary dry ball milling method, put the spheroidized base phase and dispersed phase powder into the ordinary ball mill tank in proportion, and when the ball-to-material ratio is 1 : 0.1 and rotating speed is ball milling 3h under the condition of 150r/min, obtains the spheroidization granulation ceramic powder of uniform mixing. Other steps are the same as those in Embodiments 1 to 6.

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

Specific embodiment nine: the difference between this embodiment and specific embodiment one to eight is: the process of electrospray granulation described in step 4 is completed according to the following steps:

①. Preparation of EFI slurry:

Disperse the mixed ceramic powder in the water-based dispersant, then sonicate for 30-100 minutes, then add the pore-forming agent, and heat and stir in a water bath at 40-70°C for 6-18 hours to obtain a uniform electrospray slurry;

The water-based 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 and pore-forming agent described in step ① is (2～5):1;

The mass ratio of the mixed ceramic powder and the aqueous dispersant described in step 1. is 1:(0.5～2);

②, EFI granulation:

Load the EFI slurry into the electrospray syringe with positive voltage, the needle tip voltage is 10-30kV, the needle size is 0.5-2mm, the discharge speed is 0.5-2mg/s, the receiving container is deionized water, and the obtained suspension;

③. Post-treatment of microspheres:

Filter the suspension, then dry the solid matter at 60-120°C for 3-24 hours to obtain dry spherical granulated powder; calcinate the dried spherical granulated powder at 1000-1500°C for 1-6 hours, Obtain spherical porous electrospray granulation feeding powder;

The technique of the spray granulation described in the step 4 is finished in the following steps:

Disperse 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%; m/s, temperature 100°C-220°C and spray pump pressure 1-5MPa to carry out spray granulation to obtain spray granulation feeding powder. Other steps are the same as those in Embodiments 1 to 8.

Embodiment 10: The difference between this embodiment and Embodiments 1 to 9 is that the parameters of the plasma spraying described in Step 5 are: the current is 500A-700A, the main air flow is 30-55 slpm, and the auxiliary air flow is 3-10 slpm , the carrier air flow is 1slpm-5slpm, and the powder feeding rate is 1-5rpm; the thickness of the high-strength/low thermal conductivity/radiation penetration-resistant functional surface layer described in step five is 20μm-500μm; the high-strength toughness/ The low thermal conductivity/anti-radiation penetration functional surface layer has a dispersed particle system structure, that is, micropores and functional disperse phases are evenly distributed in the base phase ceramics, where the equivalent radius of the micropores is 0.5-5 μm, and the equivalent radius of the functional disperse phase The radius is 0.3-10 μm, the porosity of the surface layer is 5%-20%, and the volume fraction of micropores and functional dispersed phases in the surface layer is 5-50%; the high strength and toughness/low thermal conductivity/thermal radiation resistance described in step five The thermal conductivity of the penetrating integrated thermal barrier ceramic coating is less than 1W/(m·K), the bonding strength is greater than 25MPa, the hardness is greater than 2.5GPa, the fracture toughness is greater than 2.5MPa·m ^1/2 , and the infrared radiation in the 0.3-10μm band The reflectivity 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.

Adopt the following examples to verify the beneficial effects of the present invention:

Example 1: The preparation method of Y ₃ NbO ₇ -GdTaO ₄ high strength and toughness/low thermal conductivity/anti-thermal radiation penetration integrated thermal barrier ceramic coating is completed according to the following steps:

1. Substrate surface pretreatment:

First remove the oxide film and grease on the surface of the substrate, then roughen the surface of the substrate, and finally perform thermal spraying preheating on the surface of the substrate;

The substrate described in step one is a high-temperature nickel-based alloy (GH4061);

The method for removing the oxide film and grease on the surface of the substrate in step 1 is: first use sandpaper to polish the substrate, and then use absolute ethanol to remove the oil on the surface;

The method for roughening the surface of the substrate in step 1 is: under a pressure of 0.3 MPa, use 45# corundum sand to perform sandblasting on the substrate to obtain a pretreated substrate, and the surface roughness of the substrate is 2 μm;

The thermal spraying preheating temperature described in step 1 is 800°C;

2. Prepare the bonding layer:

The adhesive layer powder is sprayed onto the surface of the workpiece by the atmospheric plasma spraying process to obtain a substrate with an adhesive layer;

The bonding layer powder described in step 2 is NiCrAlY;

The process of atmospheric plasma spraying described in step 2 is: the current is 580A, the main air flow is 40 slpm, the auxiliary air flow is 3.5 slpm, the carrier air flow is 3.2 slpm, and the powder feeding rate is 3 rpm;

The thickness of the adhesive layer on the substrate with the adhesive layer described in step 2 is 80 μm;

3. Preparation of ceramic base phase components and dispersed phase functional ceramic components:

Prepare ceramic base phase component Y ₃ NbO ₇ and dispersed phase functional ceramic component GdTaO ₄ by solid state reaction;

In step 3, Y ₂ O ₃ and Nb ₂ O ₅ are reacted in solid state to obtain Y ₃ NbO ₇ ; Gd ₂ O ₃ and Ta ₂ O ₅ are reacted in solid state to obtain GdTaO ₄ ;

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 Y ₃ NbO ₇ is 11 ×10 ^-6 K ^-1 ; the thermal conductivity of GdTaO ₄ is 1.7W/(m·K), the thermal conductivity of Y ₃ NbO ₇ is 1.5W/(m·K); the data of GdTaO ₄ is monoclinic, Y ₃ NbO ₇ belongs to the cubic crystal system, and there is no infinite solid solution effect between the two phases; GdTaO ₄ has ferroelastic phase transition characteristics; the primary particle size of GdTaO ₄ is 1 μm, and the primary particle size of the base ceramic Y ₃ NbO ₇ is 3 μm;

4. Mixing and spherical granulation of functional ceramic powder:

Weigh the ceramic base phase components and dispersed phase functional ceramic components in proportion, and then carry out powder mixing and spherical granulation treatment on the weighed ceramic base phase components and dispersed phase functional ceramic components to obtain spherical mixed powder feeding;

The molar ratio of the ceramic base phase component and the dispersed phase functional ceramic component described in step 4 is 5:1;

In step 4, the powder is firstly mixed and then spheroidized and granulated. The mixing process is as follows: put the mixed powder, absolute ethanol and zirconia balls into the planetary ball mill at a mass ratio of 1:0.1:3, and Ball mill at 200r/min-400r/min for 6h-12h to obtain slurry, and then dry the slurry at 60°C-120°C for 3h-12h to obtain mixed ceramic powder; Spray granulation is completed according to the following steps:

①. Preparation of EFI slurry:

Disperse the mixed ceramic powder in the water-based dispersant, then sonicate for 50 minutes, then add the pore-forming agent, and heat and stir in a water bath at 60°C for 12 hours to obtain a uniform electrospray slurry;

The aqueous dispersant described in step 1. is N-methylpyrrolidone;

The pore-forming agent described in step 1. is polyethersulfone;

The mass ratio of the mixed ceramic powder and pore-forming agent described in step 1. is 3:1;

The mass ratio of the mixed ceramic powder and the aqueous dispersant described in step 1. is 1:1;

②, EFI granulation:

Load the electrospray slurry into the electrospray syringe with positive voltage, the needle tip voltage is 20kV, the needle size is 0.5mm, the discharge speed is 0.5mg/s, and the receiving container is deionized water to obtain the suspension;

③. Post-treatment of microspheres:

Filter the suspension, and then dry the solid matter at 120°C for 8 hours to obtain a dry spherical granulated powder; calcinate the dried spherical granulated powder at 1200°C for 6 hours to obtain a spherical porous ESP Granular feed powder; the particle size of the spherical porous electrospray granulation feed powder is about 28 μm, and the porosity is 20%;

5. Preparation of functional surface layer with high strength and toughness/low thermal conductivity/radiation penetration resistance:

Using the method of plasma spraying, the spheroidized mixed powder feed is sprayed on the surface of the substrate with a bonding layer, and a functional surface layer with high toughness/low thermal conductivity/radiation penetration resistance is prepared on the surface of the substrate to obtain Y ₃ NbO ₇ -GdTaO ₄ high strength and toughness/low thermal conductivity/anti-thermal radiation penetration integrated thermal barrier ceramic coating.

The parameters of plasma spraying described in step five are: current is 550A, main air flow is 45 slpm, auxiliary air flow is 3.3 slpm, carrier air flow is 3.2 slpm, powder feeding rate is 3 rpm; high strength and toughness/low thermal conductivity/radiation resistance described in step five The thickness of the penetrating functional surface layer is 220 μm; the high-strength/low thermal conductivity/radiation penetration-resistant functional surface layer described in step five has a dispersed particle system structure, that is, micropores and functional dispersed phases are evenly distributed in the base phase ceramics In the middle, it consists of micropores with an average equivalent radius of 2 μm and GdTaO ₄ with an average equivalent radius of 5 μm dispersed in Y ₃ NbO ₇ , the porosity of the coating is 11%, and the micropores and GdTaO ₄ account for the coating The volume fraction is 27%;

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

Fig. 2 is the morphology diagram of the spherical porous electrospray granulation feeding powder prepared in step 4 of embodiment 1;

It can be seen from Figure 2 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.

Figure 3 is an XRD spectrum, in which 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;

It can be seen from Figure 3 that the original powder can be confirmed to be Y ₃ NbO ₇ and GdTaO ₄ , and when the composite feed is thermally sprayed on the surface of the nickel-based alloy, there are still two phases of Y ₃ NbO ₇ and GdTaO ₄ , which proves that Y ₃ NbO ₇ and GdTaO ₄ can exist in a multi-phase structure, and will not form a single phase in solid solution, which provides conditions for optical scattering at the heterogeneous interface and improves the reflectivity of the coating;

Fig. 4 is the SEM image of the surface of Y ₃ NbO ₇ -GdTaO ₄ high toughness/low thermal conductivity/anti-thermal radiation penetration integrated thermal barrier ceramic coating prepared in Step 5 of Example 1;

It can be seen from Fig. 4 that Example 1 successfully prepared a composite ceramic coating structure in which GdTaO ₄ is dispersed in Y ₃ NbO ₇ .

Fig. 5 is a ferroelastic domain structure diagram of GdTaO ₄ in the Y ₃ NbO ₇ -GdTaO ₄ high toughness/low thermal conductivity/thermal radiation penetration resistance integrated thermal barrier ceramic coating prepared in step 5 of Example 1;

It can be seen from FIG. 5 that GdTaO ₄ has a remarkable ferroelastic domain structure, which verifies that the second phase described in Step 3 of Example 1 has ferroelastic phase transition characteristics.

Fig. 6 is the cross-sectional morphology of the Y ₃ NbO ₇ -GdTaO ₄ high-strength/low thermal conductivity/anti-thermal radiation penetration integrated thermal barrier ceramic coating prepared in Step 5 of Example 1;

It can be seen from Figure 6 that the thickness of the Y ₃ NbO ₇ -GdTaO ₄ high-strength/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.

Figure 7 is the spectral reflectance spectrum of the coating, in which 1 is Y ₃ NbO ₇ , and 2 is the Y ₃ NbO ₇ -GdTaO ₄ high-strength/low thermal conductivity/anti-thermal radiation penetration integrated heat treatment prepared in Step 5 of Example 1. barrier ceramic coating.

In this example, a Fourier spectrometer is used to test the spectral response characteristics of the Y ₃ NbO ₇ -GdTaO ₄ high-strength/low thermal conductivity/thermal radiation penetration-resistant 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/low thermal conductivity/thermal radiation penetration-resistant integrated thermal barrier ceramic coating prepared in Step 5 of this embodiment has a reflectance of 0.88 in the 0.3-10 μm band, as shown in FIG. 7 .

In this example, a LFA457 laser thermal conductivity meter is used to measure the thermal conductivity of the Y ₃ NbO ₇ -GdTaO ₄ high-strength/low thermal conductivity/thermal radiation penetration-resistant 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/low thermal conductivity/thermal radiation penetration-resistant integrated thermal barrier ceramic coating prepared in Step 5 is 0.56W/(m·K) at 1000°C.

The Y ₃ NbO ₇ -GdTaO ₄ high-strength/low thermal conductivity/thermal radiation penetration-resistant integrated thermal barrier ceramic coating prepared in Step 5 of Example 1 has good bonding strength with the substrate, and the bonding strength is 34 MPa. At the same time, the coating has Very good thermal shock resistance, the number of thermal shock resistance cycles at room temperature and 1200 ° C is greater than 50 times, thus proving that the Y ₃ NbO ₇ -GdTaO ₄ prepared in step 5 of Example 1 prepared in this example has high strength and toughness/low thermal conductivity/ The anti-heat radiation penetration integrated thermal barrier ceramic coating has excellent thermal protection performance.

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

1. Substrate surface pretreatment:

First remove the oxide film and grease on the surface of the substrate, then roughen the surface of the substrate, and finally perform thermal spraying preheating on the surface of the substrate;

The substrate described in step 1 is a SiC substrate;

The method for removing the oxide film and grease on the surface of the substrate in step 1 is: first use sandpaper to polish the substrate, and then use absolute ethanol to remove the oil on the surface;

The method of roughening the substrate surface in step 1 is: laser roughening treatment, and the process parameters are:

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

The thermal spraying preheating temperature described in step 1 is 900°C;

2. Prepare the bonding layer:

The adhesive layer powder is sprayed onto the surface of the workpiece by the atmospheric plasma spraying process to obtain a substrate with an adhesive layer;

The bonding layer powder described in step 2 is Hf-Si;

The process of atmospheric plasma spraying described in step 2 is: the current is 600A, the main air flow is 45 slpm, the auxiliary air flow is 3.5 slpm, the carrier air flow is 3.5 slpm, and the powder feeding rate is 2.8 rpm;

The thickness of the adhesive layer on the substrate with the adhesive layer described in step 2 is 100 μm;

3. Preparation of ceramic base phase components and dispersed phase functional ceramic components:

The dispersed phase functional ceramic component NdAlO ₃ is prepared by solid state reaction method, and the ceramic base phase component YSZ is selected;

In the third step, _Nd2O3 and _Al2O3 are used to obtain _NdAlO3 through solid-state reaction; YSZ is a _commercial oxidation- _stabilized zirconia ceramic;

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 , and NdAlO The thermal conductivity of ₃ is 3.8W/(m K), the thermal conductivity of YSZ is 2.3W/(m K), NdAlO ₃ is orthorhombic, YSZ is cubic, and there is no infinite solid in the two phases. solution effect; NdAlO ₃ has ferroelastic phase transition characteristics; the original particle size of NdAlO ₃ is 1.5 μm, and that of YSZ is 5 μm;

4. Mixing and spherical granulation of functional ceramic powder:

Weigh the ceramic base phase component and the dispersed phase functional ceramic component in proportion, then perform spherical granulation on the weighed ceramic base phase component and the dispersed phase functional ceramic component, and then mix to obtain a spherical composite powder body feeding;

The molar ratio of the ceramic base phase component and the dispersed phase functional ceramic component described in step 4 is 3:1;

The granulation method of the ceramic base phase component described in step 4 is electrospray granulation, and the granulation method of the dispersed phase functional ceramic component is spray drying granulation;

The granulation method of the ceramic matrix phase component described in step 4 adopts electrospray granulation, and is specifically completed according to the following steps:

①. Preparation of EFI slurry:

Dissolve YSZ powder and polyethersulfone pore-forming agent in N-methylpyrrolidone at a mass ratio of 4:1, sonicate for 50 minutes, and heat and stir in a water bath at 60°C for 12 hours to obtain a uniform electrospray slurry;

The mass ratio of the YSZ powder described in step 1. and N-methylpyrrolidone is 1:1.2;

②, EFI granulation:

Load the electrospray slurry into the electrospray syringe with positive voltage, the needle tip voltage is 20kV, the needle size is 0.76mm, the discharge speed is 0.5mg/s, and the receiving container is deionized water to obtain the suspension;

③. Post-treatment of microspheres:

Filter the suspension, then dry the solid matter at 100°C for 12 hours to obtain dry spherical granulated powder; calcinate the dried spherical granulated powder at 1200°C for 4 hours to obtain spherical porous YSZ electrospray Granulation feed powder; the spherical porous YSZ electrospray granulation feed powder has a particle size of about 50 μm and a porosity of 18%;

The granulation method of the dispersed phase functional ceramic component NdAlO ₃ is spray-drying granulation, which is completed according to the following steps:

Disperse phenylacetic acid, polyvinyl alcohol and _NdAlO3 ceramic powder in deionized water at a mass ratio of 1:1:4 to obtain a slurry with a solid content of 30%; Spray granulation at 160°C and spray pump pressure 3MPa to obtain spheroidized NdAlO ₃ feed powder;

In step 4, the spherical porous YSZ electrospray granulation feed powder and the spherical NdAlO ₃ feed powder are mixed by ordinary ball milling, that is, the spherical porous YSZ electrospray granulation feed powder And the spheroidized _NdAlO3 feed powder is weighed according to the mass ratio of 1:3, and then the _ZrO2 ball and the above-mentioned mixed feed are put into the ordinary ball mill tank according to the ball-to-material ratio of 1:0.1, and the speed is 150r Ball milling for 3 hours at 1/min to obtain spheroidized composite powder feed;

5. Preparation of functional surface layer with high strength and toughness/low thermal conductivity/radiation penetration resistance:

Using the method of plasma spraying, the spheroidized composite powder feed is sprayed onto the surface of the substrate with a bonding layer, and a functional surface layer with high toughness/low thermal conductivity/radiation penetration resistance is prepared on the surface of the substrate to obtain YSZ-NdAlO ₃ High toughness/low thermal conductivity/anti-thermal radiation penetration integrated thermal barrier ceramic coating.

The parameters of plasma spraying described in step five are: current is 600A, main air flow is 45 slpm, auxiliary air flow is 3.5 slpm, carrier air flow is 3.2 slpm, powder feeding rate is 3 rpm; the high strength and toughness/low thermal conductivity/radiation resistance described in step five The thickness of the penetrating functional surface layer is 220 μm; the high-strength/low thermal conductivity/radiation penetration-resistant functional surface layer described in step five has a dispersed particle system structure, that is, micropores and functional dispersed phases are evenly distributed in the base phase ceramics In the middle, it is composed of micropores with an average equivalent radius of 1.5 μm and NdAlO ₃ with an average equivalent radius of 3.5 μm dispersedly distributed in YSZ, the porosity of the coating is 9%, and the micropores and NdAlO ₃ account for the coating. The volume fraction is 24%;

The thermal conductivity of the YSZ- _NdAlO3 high-strength/low thermal conductivity/thermal radiation penetration-resistant integrated thermal barrier ceramic coating described in step five is 0.85W/(m K), and the bonding strength with the substrate is 23Mpa, The hardness is 2.6Gpa, the fracture toughness is 3.2MPa·m ^1/2 , the infrared reflectance in the 0.3-10μm band 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 high-strength/low thermal conductivity/thermal radiation penetration-resistant integrated thermal barrier ceramic coating prepared in step 5 of this example. The measurement results show that this example The YSZ-NdAlO ₃ high-strength/low thermal conductivity/thermal radiation penetration-resistant integrated thermal barrier ceramic coating prepared in step five has a reflectance of 0.87 in the 0.3-10 μm band.

In this embodiment, a LFA457 laser thermal conductivity meter is used to measure the thermal conductivity of the YSZ-NdAlO ₃ high-strength/low thermal conductivity/thermal radiation penetration-resistant integrated thermal barrier ceramic coating prepared in Step 5 of this embodiment. The results show that the thermal conductivity of the YSZ-NdAlO ₃ high-strength/low thermal conductivity/thermal radiation penetration-resistant integrated thermal barrier ceramic coating prepared in step five is 0.85W/(m·K) at 1000°C.

The YSZ-NdAlO ₃ high strength and toughness/low thermal conductivity/thermal radiation penetration resistance integrated thermal barrier ceramic coating prepared in step 5 of Example 2 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, the number of thermal shock resistance cycles at room temperature and 1200 ° C is greater than 50, thus proving that the YSZ-NdAlO ₃ high-strength/low thermal conductivity/thermal radiation penetration-resistant integrated thermal barrier ceramic coating prepared in this example has Excellent thermal protection properties.

Comparative example 1: Al ₂ O ₃ doped Y ₃ NbO ₇ ceramic coating preparation method, is to complete as follows:

1. Substrate surface pretreatment:

First remove the oxide film and grease on the surface of the substrate, then roughen the surface of the substrate, and finally perform thermal spraying preheating on the surface of the substrate;

The substrate described in step 1 is a high-temperature nickel-based alloy (GH4061); the method for removing the oxide film and grease on the surface of the substrate in step 1 is: firstly use sandpaper to polish the substrate, and then use absolute ethanol to remove the oil on the surface;

The method for roughening the surface of the substrate in step 1 is: under a pressure of 0.3 MPa, use 45# corundum sand to perform sandblasting on the substrate to obtain a pretreated substrate, and the surface roughness of the substrate is 2 μm;

The thermal spraying preheating temperature described in step 1 is 800°C;

2. Prepare the bonding layer:

The adhesive layer powder is sprayed onto the surface of the workpiece by the atmospheric plasma spraying process to obtain a substrate with an adhesive layer;

The bonding layer powder described in step 2 is NiCrAlY;

The process of atmospheric plasma spraying described in step 2 is: the current is 580A, the main air flow is 40 slpm, the auxiliary air flow is 3.5 slpm, the carrier air flow is 3.2 slpm, and the powder feeding rate is 3 rpm;

The thickness of the adhesive layer on the substrate with the adhesive layer described in step 2 is 80 μm;

3. Preparation of ceramic base phase components and dispersed phase functional ceramic components:

The ceramic base phase component Y ₃ NbO ₇ is prepared by solid state reaction, and Al ₂ O ₃ is selected as the dispersed phase functional ceramic component;

In step 3, Y ₂ O ₃ and Nb ₂ O ₅ are reacted in solid state to obtain Y ₃ NbO ₇ ; commercial Al ₂ O ₃ is used;

The refractive index n of Al ₂ O ₃ described in step 3 is 1.75, and the refractive index n of Y ₃ NbO ₇ is 1.7 (the difference in dielectric function between the two is too small); the thermal expansion coefficient of Al ₂ O ₃ is 7.45× 10 ^-6 K ^-1 , 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 7.8W/(m·K) , the thermal conductivity of Y ₃ NbO ₇ is 1.5W/(m·K) (the thermal conductivity of Al ₂ O ₃ is too large); Al ₂ O ₃ belongs to the hexagonal crystal system, Y ₃ NbO ₇ belongs to the cubic crystal system, and the two Phase does not have infinite solid solution effect; Al ₂ O ₃ does not have ferroelastic phase transition characteristics (cannot play 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 3μm;

4. Mixing and spherical granulation of functional ceramic powder:

Weigh the ceramic base phase components and dispersed phase functional ceramic components in proportion, and then carry out powder mixing and spherical granulation treatment on the weighed ceramic base phase components and dispersed phase functional ceramic components to obtain spherical mixed powder feeding;

The molar ratio of the ceramic base phase component and the dispersed phase functional ceramic component described in step 4 is 5:1;

In step 4, the powder is firstly mixed and then spheroidized and granulated. The mixing process is as follows: put the mixed powder, absolute ethanol and zirconia balls into the planetary ball mill at a mass ratio of 1:0.1:3, and Ball mill at a speed of 300r/min for 8 hours to obtain a slurry; dry the slurry at 100°C for 6 hours to obtain a mixed powder after ball milling;

The mixed powder after ball milling is granulated by electrospray, which is completed according to the following steps:

①. Preparation of EFI slurry:

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

The mass ratio of the mixed powder after ball milling described in step 1. to N-methylpyrrolidone is 1:1;

②, EFI granulation:

Load the electrospray slurry into the electrospray syringe with positive voltage, the needle tip voltage is 20kV, the needle size is 0.5mm, the discharge speed is 0.5mg/s, and the receiving container is deionized water to obtain the suspension;

③. Post-treatment of microspheres:

Filter the suspension, and then dry the solid matter at 120°C for 8 hours to obtain a dry spherical granulated powder; calcinate the dried spherical granulated powder at 1200°C for 6 hours to obtain a spherical porous ESP Granular feed powder; the particle size of the spherical porous electrospray granulation feed powder is about 26 μm, and the porosity is 19%;

5. Preparation of functional surface layer with high strength and toughness/low thermal conductivity/radiation penetration resistance:

The plasma spraying method is used to spray the spheroidized mixed powder feed on the surface of the substrate with the bonding layer to obtain a ceramic coating of Al ₂ O ₃ doped Y ₃ NbO ₇ .

The process of plasma spraying described in step 5 is: the current is 550A, the main air flow is 45 slpm, the auxiliary air flow is 3.3 slpm, the carrier air flow is 3.2 slpm, and the powder feeding rate is 3.5 rpm; the thickness of the surface layer described in step 2 is 220 μm;

The Al ₂ O ₃ doped Y ₃ NbO ₇ ceramic coating described in Step 5 is composed of micropores with an average equivalent radius of 1.8 μm and Al ₂ O ₃ with an average equivalent radius of 4 μm dispersed in Y ₃ NbO ₇ , the porosity of the coating is 10%, and the volume fraction of micropores and Al ₂ O ₃ in the coating is 25%;

In this example, a Fourier spectrometer is used to test the spectral response characteristics of the Al ₂ O ₃ doped Y ₃ NbO ₇ ceramic coating prepared in step 5 of this example. The measurement results show that the Al ₂ O ₃ prepared in step 5 of this example The reflectance of the ceramic coating doped with Y ₃ NbO ₇ in the 0.5-10 μm band is 0.65.

In this embodiment, an LFA457 laser thermal conductivity meter is used to measure the thermal conductivity of the Al ₂ O ₃ doped Y ₃ NbO ₇ ceramic coating prepared in Step 5 of this embodiment. The results show that the thermal conductivity of the Al ₂ O ₃ doped Y ₃ NbO ₇ ceramic coating prepared in Step 5 is 1.54W/(m·K) at 1000°C.

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

Claims (10)

1. A preparation method of a high-strength and high-toughness/low-heat-conductivity/thermal-radiation-penetration-resistant integrated thermal barrier ceramic coating is characterized by comprising the following steps of:

1. Pretreatment of the surface of a substrate:

firstly removing an oxide film and grease on the surface of a substrate, then coarsening the surface of the substrate, and finally carrying out thermal spraying preheating treatment on the surface of the substrate;

2. preparing a bonding layer:

spraying the bonding layer powder on the surface of a workpiece by adopting an atmospheric plasma spraying process to obtain a substrate with a bonding layer;

3. preparing a ceramic-based phase component and a disperse phase functional ceramic component:

preparing ceramic-based phase components and disperse phase functional ceramic components by adopting a sol-gel or solid phase reaction method;

4. mixing and ball granulating functional ceramic powder:

weighing ceramic-based phase components and disperse phase functional ceramic components according to a proportion, and then carrying out powder mixing and sphericizing granulation treatment on the weighed ceramic-based phase components and disperse phase functional ceramic components to obtain a sphericized composite feed;

5. preparing a high-strength and high-toughness/low-heat-conductivity/radiation-penetration-resistant functional surface layer:

and spraying the spherical composite feed on the surface of the substrate with the bonding layer by adopting a plasma spraying method, and preparing a high-toughness/low-thermal-conductivity/radiation-penetration-resistant functional surface layer on the surface of the substrate to obtain the high-toughness/low-thermal-conductivity/thermal-radiation-penetration-resistant integrated thermal barrier ceramic coating.

2. The method for preparing a high strength and toughness/low thermal conductivity/thermal radiation penetration resistant integrated thermal barrier ceramic coating according to claim 1, wherein the substrate in the first step is a metal-based material or a ceramic-based material; the metal-based material is titanium-aluminum alloy, nickel-based alloy or niobium-based alloy; the ceramic-based material is C/C, siC/SiC, C/SiC or SiC/Si ₃ N ₄ The method comprises the steps of carrying out a first treatment on the surface of the In step oneThe method for removing the oxide film and grease on the surface of the matrix comprises the steps of polishing a substrate by using sand paper to remove the oxide film, and then removing the grease on the matrix by adopting one or more of a solvent cleaning method, a steam cleaning method, an alkaline cleaning method and a heating degreasing method; the roughening treatment method for the surface of the matrix is sand blasting treatment or laser roughening treatment, wherein the sand blasting treatment is adopted when the matrix is a metal matrix material, and the laser roughening treatment is adopted when the matrix is a ceramic matrix material; the parameters of the sand blasting treatment are as follows: the sand grain size is 15-50 # and the sand blasting pressure is 0.3-0.7 MPa; the laser texturing parameters are as follows: the laser power is 1-8 kW, the pulse frequency is 10-20 Hz, the spot size is 10-100 mu m, and the roughness of the surface of the obtained texturing substrate is 1-5 mu m; the preheating temperature of the thermal spraying in the first step is 600-900 ℃.

3. The method for preparing the high-strength and high-toughness/low-thermal-conductivity/thermal-radiation-penetration-resistant integrated thermal barrier ceramic coating according to claim 1, wherein the bonding layer powder in the second step is selected according to the type of a substrate, and when the substrate is a metal-based material, the bonding layer powder is selected from MCrAlY, wherein M is Ni, co or NiCo; when the matrix is subjected to laser texturing treatment, the bonding layer powder is RE-Si, wherein RE is a rare earth element, and the rare earth element is Hf or Y; the process of the atmospheric plasma spraying in the second step comprises the following steps: the current is 600A-650A, the main air flow is 40-50 slpm, the auxiliary air flow is 3-10 slpm, the carrier gas flow is 1-5 slpm, and the powder feeding amount is 1-3 rpm; the thickness of the bonding layer on the substrate with the bonding layer in the second step is 20-200 mu m.

4. The method for preparing the high-toughness/low-thermal-conductivity/thermal-radiation-penetration-resistant integrated thermal barrier ceramic coating according to claim 1, wherein the dielectric function N of the ceramic-based phase component and the dielectric function N of the disperse-phase functional ceramic component have a large difference, that is, the absolute value of the difference between the refractive indexes N of the ceramic-based phase component and the disperse-phase functional ceramic component needs to be larger than 0.3 or the absolute value of the difference between the extinction coefficients k of the ceramic-based phase component and the disperse-phase functional ceramic component needs to be larger than 1; the dielectric function n=n+ik, where N is the refractive index of the ceramic and i is the imaginary symbol; k is the extinction coefficient of the ceramic.

5. The method for preparing a high strength and toughness/low thermal conductivity/thermal radiation penetration resistant integrated thermal barrier ceramic coating according to claim 1, wherein the absolute value of the difference between the coefficients of thermal expansion of the ceramic-based phase component and the dispersed phase functional ceramic component in step three is less than 1.5X10 ^-6 K ^-1 The method comprises the steps of carrying out a first treatment on the surface of the The thermal conductivity of the ceramic-based phase component in the third step is less than 3W/(m.K); the ceramic-based phase component is yttria stabilized zirconia or rare earth niobate, zirconate or hafnate with fluorite or pyrochlore crystal structure; the disperse phase functional ceramic component in the third step is a ceramic component with high Wen Tiedan phase change characteristic and low thermal conductivity less than 5W/(m.K); the disperse phase functional ceramic component is rare earth tannate or aluminate.

6. The method for preparing the high-strength and high-toughness/low-thermal-conductivity/thermal-radiation-penetration-resistant integrated thermal barrier ceramic coating according to claim 1, wherein the ceramic-based phase component and the dispersed phase functional ceramic component in the third step belong to different crystal systems, and an infinite solid solution effect does not exist between the ceramic-based phase component and the dispersed phase functional ceramic component; and step three, preparing the powder particle size of the ceramic matrix phase component to be 1-10 mu m, and preparing the powder particle size of the disperse phase functional ceramic component to be less than 3 mu m.

7. The method for preparing the high-strength and high-toughness/low-thermal-conductivity/thermal-radiation-penetration-resistant integrated thermal barrier ceramic coating according to claim 1, wherein the molar ratio of the ceramic-based phase component to the dispersed phase functional ceramic component in the fourth step is (3-20): 1; the powder mixing and ball granulating treatment process in the fourth step is not in sequence; when powder mixing is carried out firstly and then ball granulating treatment is carried out, the mixing process is as follows: placing a certain proportion of original powder of a base phase and a dispersion functional phase, absolute ethyl alcohol and zirconia balls into a planetary ball milling tank machine according to a mass ratio of 1:0.1:3, ball milling for 6-12 hours at a rotating speed of 200-400 r/min to obtain mixed slurry of the original powder, drying the slurry at 60-120 ℃ for 3-12 hours to obtain original ceramic powder in which the base phase and the dispersion phase are uniformly mixed, and then performing spherical granulation treatment on the mixed original powder; when the spherical granulation treatment is carried out and then the mixture is carried out, the mixing process of the granulation powder is as follows: and (3) putting the spherical base phase and the dispersed phase powder into a common ball milling tank according to a proportion by adopting a common dry ball milling mode, and ball milling for 3 hours under the conditions that the ball-to-material ratio is 1:0.1 and the rotating speed is 150r/min to obtain the uniformly mixed spherical granulated ceramic powder.

8. The method for preparing the high-strength and high-toughness/low-thermal-conductivity/thermal-radiation-penetration-resistant integrated thermal barrier ceramic coating according to claim 1, wherein the spherical granulating mode in the fourth step is one or two of electrospray granulating and spray granulating; the particle size of the spherical composite powder feed in the fourth step is 1-100 mu m.

9. The method for preparing the high-strength and high-toughness/low-thermal-conductivity/thermal-radiation-penetration-resistant integrated thermal barrier ceramic coating according to claim 8, wherein the process of electrospray granulation in the fourth step is completed according to the following steps:

(1) preparing an electrospray slurry:

dispersing the mixed ceramic powder in a water-based dispersing agent, performing ultrasonic treatment for 30-100 min, adding a pore-forming agent, and heating and stirring in a water bath at 40-70 ℃ for 6-18 h to obtain uniform electrospray slurry;

the water-based dispersing agent in the step (1) is one or two of polyvinylpyrrolidone and N-methyl pyrrolidone;

the pore-forming agent in the step (1) is polyethersulfone or polytetrafluoroethylene;

the mass ratio of the mixed ceramic powder to the pore-forming agent in the step (1) is (2-5): 1;

the mass ratio of the mixed ceramic powder to the water-based dispersing agent in the step (1) is 1 (0.5-2);

(2) And (3) electrospraying granulation:

loading the electric spraying slurry into an electric spraying needle cylinder with positive voltage, wherein the voltage of the tip end of the needle cylinder is 10-30 kV, the size of a needle head is 0.5-2 mm, the discharging speed is 0.5-2 mg/s, and a receiving container selects deionized water to obtain suspension;

(3) and (3) microsphere post-treatment:

filtering the suspension, and drying the solid matter at 60-120 ℃ for 3-24 hours to obtain dried spherical granulating powder; calcining the dried spherical granulating powder at 1000-1500 ℃ for 1-6 h to obtain spherical porous electrospraying granulating feeding powder;

the spray granulation process in the fourth step is completed according to the following steps:

dispersing phenylacetic acid, polyvinyl alcohol and mixed ceramic powder in deionized water according to a mass ratio of 1:1 (3-6) to obtain slurry, wherein the solid content of the slurry is 20-40%; and then spray granulating at the hot air speed of 0.3-0.6 m/s, the temperature of 100-220 ℃ and the spray pump pressure of 1-5 MPa to obtain spray granulating feeding powder.

10. The method for preparing the high-strength and high-toughness/low-thermal-conductivity/thermal-radiation-penetration-resistant integrated thermal barrier ceramic coating according to claim 1, wherein the parameters of plasma spraying in the fifth step are as follows: the current is 500A-700A, the main air flow is 30-55 slpm, the auxiliary air flow is 3-10 slpm, the carrier gas flow is 1-5 slpm, and the powder feeding amount is 1-5 rpm; the thickness of the high-strength and high-toughness/low-heat-conductivity/radiation-penetration-resistant functional surface layer in the fifth step is 20-500 mu m; the functional surface layer with high toughness/low thermal conductivity/radiation penetration resistance has a dispersed particle system structure, namely micropores and functional dispersed phases are uniformly distributed in the base phase ceramic, wherein the equivalent radius of the micropores is 0.5-5 mu m, the equivalent radius of the functional dispersed phases is 0.3-10 mu m, the porosity of the surface layer is 5-20%, and the volume fraction of the micropores and the functional dispersed phases in the surface layer is 5-50%; the thermal conductivity of the high-strength and high-toughness/low-thermal conductivity/thermal radiation penetration resistant integrated thermal barrier ceramic coating in the fifth step is less than 1W/(m.K), the bonding strength is more than 25MPa, the hardness is more than 2.5GPa, and the fracture toughness is more than 2.5 MPa.m ^1/2 The infrared reflectivity is more than 0.8 and the infrared transmissivity is less than 0.15 in the wave band of 0.3-10 mu m.

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