A high-temperature resistant and thermal shock resistant thermal barrier coating for nickel-based alloy surfaces and its preparation method

Abstract

This invention discloses a high-temperature resistant and thermal shock resistant thermal barrier coating for nickel-based alloy surfaces and its preparation method. The thermal barrier coating, from bottom to top, consists of a first adhesive layer, a second adhesive layer, a ceramic transition layer, and a ceramic layer. The first or second adhesive layer is made of one or more of NiCoCrAlY, NiCrAlY, or NiCoCrAlYTa, with the first adhesive layer having a thickness of 70-80 µm and the second adhesive layer having a thickness of 50-70 µm. The ceramic transition layer or ceramic layer is made of RETaO4 mixed with one of YSZ and Gd₂Zr₂O₇, where RE is one or more of Y, Gd, and Ho. The molar ratio of RETaO4 to YSZ or Gd₂Zr₂O₇ is 1-3:1. The thickness of the ceramic transition layer is 100-120 µm, and the thickness of the ceramic layer is 200-320 µm. The thermal barrier coating for nickel-based alloy surfaces provided by this invention exhibits significantly better thermal insulation and thermal shock resistance than existing technologies, making it suitable for widespread application.

Description

Technical Field

[0001] This invention belongs to the field of ceramic coating technology, specifically relating to a high-temperature resistant and thermal shock resistant thermal barrier coating for nickel-based alloy surfaces and its preparation method. Background Technology

[0002] Nickel-based alloys are a class of alloys with nickel as the main component, widely used in many demanding applications due to their excellent properties. Nickel-based alloys maintain high strength at high temperatures, possess excellent oxidation resistance and corrosion resistance, and exhibit good toughness, ductility, and fatigue resistance, maintaining stable mechanical properties for extended periods under extreme conditions. Furthermore, adding different types of metallic elements to nickel-based alloys and controlling their composition and microstructure can further enhance their properties, thereby expanding their application range. However, with the development of aerospace, engine inlet temperatures are far higher than the melting point of nickel-based alloys, making thermal barrier coating systems a crucial solution to address the high-temperature resistance issues of nickel-based alloys. Since engines experience alternating periods of heating and cooling during operation, the thermal shock resistance of the thermal barrier coating is also essential.

[0003] Thermal barrier coatings widely used in nickel-based alloys include: single-layer adhesive layer with single-layer ceramic layer, single-layer adhesive layer with double-layer ceramic layer, and double-layer adhesive layer with double-layer ceramic layer systems. However, the single-layer adhesive layer system, due to the lack of varying thermal insulation gradients at the adhesive layer, results in an insulation temperature of around 200℃, which does not meet the required insulation capacity. Meanwhile, the double-layer adhesive layer system, due to the increased number of layers leading to decreased bonding strength, exhibits weak thermal shock resistance (approximately 100 water quenching cycles after holding at 1200℃ for 10 minutes).

[0004] The present invention aims to provide a thermal barrier coating for nickel-based alloy surfaces with excellent thermal insulation and thermal shock resistance. Summary of the Invention

[0005] The first objective of this invention is to provide a high-temperature resistant and thermal shock resistant thermal barrier coating for the surface of a nickel-based alloy. The second objective of this invention is to provide a method for preparing the high-temperature resistant and thermal shock resistant thermal barrier coating for the surface of the nickel-based alloy.

[0006] The first objective of this invention is achieved as follows: a high-temperature resistant and thermal shock resistant thermal barrier coating for nickel-based alloy surfaces, wherein the thermal barrier coating is composed of a first adhesive layer, a second adhesive layer, a ceramic transition layer and a ceramic layer from bottom to top;

[0007] The material of the first or second adhesive layer is one or more of NiCoCrAlY, NiCrAlY, or NiCoCrAlYTa, the thickness of the first adhesive layer is 70-80µm, and the thickness of the second adhesive layer is 50-70µm; the molar ratio of RETaO4 to YSZ or Gd2Zr2O7 is 1-3:1;

[0008] The ceramic transition layer or ceramic layer is composed of RETaO4 and one of YSZ and Gd2Zr2O7, wherein RE is one or more of Y, Gd, and Ho.

[0009] The thickness of the ceramic transition layer is 100 ~ 120µm, and the thickness of the ceramic layer is 200 ~ 320µm.

[0010] The thermal barrier coating has a maximum insulation temperature of 437°C at 1500°C; the thermal shock resistance of the thermal barrier coating is: after holding at 1200°C for 10 minutes, the maximum number of water quenching cycles is 347.

[0011] The second objective of this invention is achieved by the following steps in the preparation method of the high-temperature resistant and thermal shock resistant thermal barrier coating on the surface of the nickel-based alloy:

[0012] 1) Sandblast the surface of the nickel-based alloy;

[0013] 2) The first and second bonding layers of the sandblasted nickel-based alloy were sprayed sequentially using vacuum plasma spraying and supersonic flame spraying, and then left to stand in the air for 10 to 15 minutes.

[0014] 3) The ceramic transition layer and the ceramic layer were sprayed sequentially using atmospheric plasma and supersonic flame spraying, respectively.

[0015] The beneficial effects of this invention are as follows: The thermal barrier coating applied to the surface of nickel-based alloys comprises a first adhesive layer, a second adhesive layer, a ceramic transition layer, and a ceramic layer. The first adhesive layer utilizes vacuum plasma spraying to reduce internal oxidation, while the second adhesive layer employs supersonic flame spraying to form a dense adhesive layer. Appropriate surface roughness is provided to ensure a tighter bond between the adhesive layer and the ceramic layer, improving thermal shock resistance. The ceramic transition layer and the ceramic layer, using different ratios of RETaO4 and YSZ or Gd2Zr2O7, endow the nickel-based alloy with excellent high-temperature resistance and thermal shock resistance. The thermal barrier coating for nickel-based alloy surfaces provided by this invention exhibits significantly superior thermal insulation and thermal shock resistance compared to existing technologies, making it suitable for widespread application. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall thermal barrier coating of the present invention;

[0017] Figure 2 The XRD pattern of the thermal barrier coating prepared in Example 3 of this invention;

[0018] Figure 3 This is a SEM image of the thermal barrier coating surface prepared in Example 3 of the present invention. Detailed Implementation

[0019] The present invention will be further described below, but this is not intended to limit the invention in any way. Any modifications made based on the present invention are within the scope of protection of the present invention.

[0020] This invention provides a high-temperature resistant and thermal shock resistant thermal barrier coating for nickel-based alloy surfaces, which consists of a first adhesive layer, a second adhesive layer, a ceramic transition layer, and a ceramic layer from bottom to top.

[0021] The material of the first adhesive layer or the second adhesive layer is one or more of NiCoCrAlY, NiCrAlY or NiCoCrAlYTa, the thickness of the first adhesive layer is 70 ~ 80µm, and the thickness of the second adhesive layer is 50 ~ 70µm;

[0022] The ceramic transition layer or ceramic layer is composed of RETaO4 and one of YSZ and Gd2Zr2O7, wherein RE is one or more of Y, Gd, and Ho; the molar ratio of RETaO4 to YSZ or Gd2Zr2O7 is 1~3:1.

[0023] The thickness of the ceramic transition layer is 100 ~ 120µm, and the thickness of the ceramic layer is 200 ~ 320µm.

[0024] The particle size of NiCoCrAlY, NiCrAlY, or NiCoCrAlYTa is 90 ~ 120µm.

[0025] The first adhesive layer material is NiCoCrAlY, and the second adhesive layer material is NiCoCrAlYTa;

[0026] The particle size of the YSZ, RETaO4, or Gd2Zr2O7 is 45 ~ 90 µm.

[0027] This invention also provides a method for preparing a high-temperature resistant and thermal shock resistant thermal barrier coating on the surface of the nickel-based alloy, which is implemented according to the following steps:

[0028] 1) Sandblast the surface of the nickel-based alloy;

[0029] 2) The first and second bonding layers of the sandblasted nickel-based alloy were sprayed sequentially using vacuum plasma spraying and supersonic flame spraying, and then left to stand in the air for 10 to 15 minutes.

[0030] 3) The ceramic transition layer and the ceramic layer were sprayed sequentially using atmospheric plasma and supersonic flame spraying, respectively.

[0031] In step 2), the vacuum plasma spraying process parameters are: vacuum degree 10 -4~ 10 -6 The parameters are: atm, spray gun power of 34~39kW, spray gun distance of 80~100 mm, argon and hydrogen gas flow rates of 40~50L / min and 3~7L / min respectively, powder feeding rate of 1~5L / min, and spray gun speed of 400~800mm / s.

[0032] In step 2), the supersonic flame spraying process parameters are as follows: oxygen pressure is 1 ~ 2 MPa, propane pressure is 0.3 ~ 0.7 MPa, nitrogen pressure is 0.5 ~ 0.7 MPa, oxygen flow rate is 1000 ~ 1250 L / h, propane flow rate is 1100 ~ 1200 L / h, nitrogen flow rate is 1000 ~ 1100 L / h, spray gun distance is 120 ~ 150 mm, powder feeding rate is 1 ~ 5 L / min, and spray gun speed is 300 ~ 500 mm / s.

[0033] In step 3), the vacuum plasma spraying process parameters are as follows: the spray gun power is 40~45kW, the spray gun distance is 120~150 mm, the argon and hydrogen gas flow rates are 45~50L / min and 4~8L / min respectively, the powder feeding rate is 1~5L / min, and the spray gun speed is 400~800mm / s.

[0034] In step 3), the supersonic flame spraying process parameters are as follows: oxygen pressure is 2 ~ 3 MPa, propane pressure is 0.5 ~ 1 MPa, nitrogen pressure is 0.5 ~ 0.7 MPa, oxygen flow rate is 1200 ~ 1350 L / h, propane flow rate is 1200 ~ 1400 L / h, nitrogen flow rate is 1000 ~ 1100 L / h, spray gun distance is 150 ~ 180 mm, powder feeding rate is 1 ~ 5 L / min, and spray gun speed is 200 ~ 400 mm / s.

[0035] In step 1), the material used for sandblasting is quartz sand with a particle size of 1 to 2 mm, and the pressure is 3 to 6 bar.

[0036] Example 1

[0037] 1) Use quartz sand with a particle size of 1 mm to sandblast the surface of the nickel-based alloy under a pressure of 3 bar;

[0038] 2) Apply the first adhesive layer to the nickel-based alloy after sandblasting in step 1) using vacuum plasma spraying. The parameters are: vacuum degree 10... -4The parameters for the second adhesive layer are as follows: atom pressure (ATM), spray gun power (34kW), spray gun distance (80mm), argon and hydrogen flow rates (40L / min and 3L / min respectively), powder feed rate (1L / min), and spray gun speed (400mm / s). The first adhesive layer material is NiCoCrAlY with a particle size of 90µm and a thickness of 70µm. The second adhesive layer is applied using supersonic flame spraying with the following parameters: oxygen pressure 1MPa, propane pressure 0.3MPa, nitrogen pressure 0.5MPa, oxygen flow rate 1000L / h, propane flow rate 1100L / h, nitrogen flow rate 1000L / h, spray gun distance 120mm, powder feed rate 1L / min, and spray gun speed 300mm / s. The second adhesive layer material is NiCrAlY with a particle size of 120µm and a thickness of 70µm.

[0039] 3) Allow the adhesive layer sprayed in step 2) to stand in the air for 10 minutes;

[0040] 4) The coating from step 3) after settling was sprayed with an atmospheric plasma coating to form a ceramic transition layer. The parameters were: spray gun power 40kW, spray gun distance 120mm, argon and hydrogen flow rates 45L / min and 4L / min respectively, powder feed rate 1L / min, and spray gun speed 400mm / s; the material was a 1:1 mixture of YSZ and YTaO4, with a particle size of 45µm and a thickness of 100µm. The ceramic layer was then sprayed using supersonic flame spraying, with the following process parameters: oxygen pressure 2MPa, propane pressure 0.5MPa, nitrogen pressure 0.5MPa, oxygen flow rate 1200L / h, propane flow rate 1200L / h, nitrogen flow rate 1000L / h, spray gun distance 150mm, powder feed rate 1 / min, and spray gun speed 200mm / s; the material was YSZ. 0.5 Gd 0.5 TaO4 and Gd2Zr2O7 were mixed at a molar ratio of 1:1, with a particle size of 90µm and a thickness of 320µm.

[0041] Example 2

[0042] 1) Use quartz sand with a particle size of 2mm to sandblast the surface of the nickel-based alloy under a pressure of 6 bar;

[0043] 2) Apply the first adhesive layer to the nickel-based alloy after sandblasting in step 1) using vacuum plasma spraying. The parameters are: vacuum degree 10... -6The parameters for the second adhesive layer are as follows: atom pressure (ATM), spray gun power (39kW), spray gun distance (100mm), argon and hydrogen flow rates (50L / min and 7L / min respectively), powder feed rate (5L / min), and spray gun speed (800mm / s). The first adhesive layer material is NiCrAlY with a particle size of 120µm and a thickness of 80µm. The second adhesive layer is applied using supersonic flame spraying with the following parameters: oxygen pressure 2MPa, propane pressure 0.7MPa, nitrogen pressure 0.7MPa, oxygen flow rate 1250L / h, propane flow rate 1200L / h, nitrogen flow rate 1100L / h, spray gun distance 150mm, powder feed rate 5L / min, and spray gun speed 500mm / s. The second adhesive layer material is NiCoCrAlY with a particle size of 90µm and a thickness of 50µm.

[0044] 3) Allow the adhesive layer sprayed in step 2) to stand in the air for 15 minutes;

[0045] 4) The coating from step 3) after settling was sprayed as a ceramic transition layer using atmospheric plasma. The parameters were: spray gun power 45kW, spray gun distance 150mm, argon and hydrogen flow rates 50L / min and 8L / min respectively, powder feed rate 5L / min, and spray gun speed 800mm / s; the material was a 1:1 molar ratio mixture of YSZ and HoTaO4, with a particle size of 90µm and a thickness of 120µm. The ceramic layer was then sprayed using supersonic flame spraying, with the following process parameters: oxygen pressure 3MPa, propane pressure 1MPa, nitrogen pressure 0.7MPa, oxygen flow rate 1350L / h, propane flow rate 1400L / h, nitrogen flow rate 1100L / h, spray gun distance 180mm, powder feed rate 5L / min, and spray gun speed 400mm / s. The material was YSZ. 0.5 Ho 0.5 TaO4 and Gd2Zr2O7 were mixed in a molar ratio of 2:1, with a particle size of 45µm and a thickness of 200µm.

[0046] Example 3

[0047] 1) Use quartz sand with a particle size of 2mm to sandblast the surface of the nickel-based alloy under a pressure of 4 bar;

[0048] 2) Apply the first adhesive layer to the nickel-based alloy after sandblasting in step 1) using vacuum plasma spraying. The parameters are: vacuum degree 10... -5The parameters for the second adhesive layer are as follows: atom pressure (ATM), spray gun power (37kW), spray gun distance (90mm), argon and hydrogen flow rates (45L / min and 5L / min respectively), powder feed rate (3L / min), and spray gun speed (600mm / s). The first adhesive layer material is NiCoCrAlY with a particle size of 100µm and a thickness of 75µm. The second adhesive layer is applied using supersonic flame spraying with the following parameters: oxygen pressure 2MPa, propane pressure 0.5MPa, nitrogen pressure 0.6MPa, oxygen flow rate 1150L / h, propane flow rate 1150L / h, nitrogen flow rate 1050L / h, spray gun distance 130mm, powder feed rate 3L / min, and spray gun speed 400mm / s. The second adhesive layer material is NiCoCrAlYTa with a particle size of 110µm and a thickness of 60µm.

[0049] 3) Allow the adhesive layer sprayed in step 2) to stand in the air for 12 minutes;

[0050] 4) The coating from step 3) after settling was sprayed as a ceramic transition layer using atmospheric plasma. The parameters were: spray gun power 42kW, spray gun distance 130mm, argon and hydrogen flow rates 47L / min and 8L / min respectively, powder feed rate 3L / min, and spray gun speed 600mm / s; the material was a 1:1 molar ratio mixture of Gd₂Zr₂O₇ and YTaO₄, with a particle size of 60µm and a thickness of 110µm. The ceramic layer was then sprayed using supersonic flame spraying, with the following process parameters: oxygen pressure 3MPa, propane pressure 0.8MPa, nitrogen pressure 0.6MPa, oxygen flow rate 1300L / h, propane flow rate 1300L / h, nitrogen flow rate 1100L / h, spray gun distance 160mm, powder feed rate 3L / min, and spray gun speed 300mm / s. The material was Y… 0.5 Gd 0.5 TaO4 and YSZ were mixed in a molar ratio of 3:1, with a particle size of 80µm and a thickness of 250µm.

[0051] Example 4

[0052] 1) Use quartz sand with a particle size of 1 mm to sandblast the surface of the nickel-based alloy under a pressure of 5 bar;

[0053] 2) Apply the first adhesive layer to the nickel-based alloy after sandblasting in step 1) using vacuum plasma spraying. The parameters are: vacuum degree 10... -5The parameters for the second adhesive layer are as follows: atom pressure (ATM), spray gun power (36kW), spray gun distance (100mm), argon and hydrogen flow rates (47L / min and 4L / min respectively), powder feed rate (4L / min), and spray gun speed (500mm / s). The first adhesive layer material is NiCoCrAlYTa with a particle size of 110µm and a thickness of 70µm. The second adhesive layer is applied using supersonic flame spraying with the following parameters: oxygen pressure 1MPa, propane pressure 0.4MPa, nitrogen pressure 0.7MPa, oxygen flow rate 1100L / h, propane flow rate 1100L / h, nitrogen flow rate 1100L / h, spray gun distance 140mm, powder feed rate 4L / min, and spray gun speed 300mm / s. The second adhesive layer material is NiCoCrAlY with a particle size of 100µm and a thickness of 50µm.

[0054] 3) Allow the adhesive layer sprayed in step 2) to stand in the air for 11 minutes;

[0055] 4) The coating from step 3) after settling was sprayed as a ceramic transition layer using atmospheric plasma. The parameters were: spray gun power 44kW, spray gun distance 130mm, argon and hydrogen flow rates 46L / min and 6L / min respectively, powder feed rate 4L / min, and spray gun speed 600mm / s; the material was a 1:1 molar ratio mixture of Gd₂Zr₂O₇ and HoTaO₄, with a particle size of 60µm and a thickness of 110µm. The ceramic layer was then sprayed using supersonic flame spraying, with the following process parameters: oxygen pressure 3MPa, propane pressure 0.8MPa, nitrogen pressure 0.6MPa, oxygen flow rate 1300L / h, propane flow rate 1300L / h, nitrogen flow rate 1100L / h, spray gun distance 160mm, powder feed rate 3 / min, and spray gun speed 300mm / s. The material was Y₂Zr₂O₇. 0.5 Ho 0.5 TaO4 and YSZ were mixed in a molar ratio of 2:1, with a particle size of 80µm and a thickness of 250µm.

[0056] Example 5

[0057] 1) Use quartz sand with a particle size of 2mm to sandblast the surface of the nickel-based alloy under a pressure of 6 bar;

[0058] 2) Apply the first adhesive layer to the nickel-based alloy after sandblasting in step 1) using vacuum plasma spraying. The parameters are: vacuum degree 10... -6The parameters for the second adhesive layer are as follows: atomization time (ATM), spray gun power (38 kW), spray gun distance (100 mm), argon and hydrogen flow rates (48 L / min and 6 L / min respectively), powder feed rate (5 L / min), and spray gun speed (700 mm / s). The first adhesive layer material is NiCoCrAlYTa with a particle size of 110 µm and a thickness of 70 µm. Supersonic flame spraying is used for the second adhesive layer. The parameters are: oxygen pressure 1 MPa, propane pressure 0.4 MPa, nitrogen pressure 0.7 MPa, oxygen flow rate 1100 L / h, propane flow rate 1100 L / h, nitrogen flow rate 1100 L / h, spray gun distance 140 mm, powder feed rate 2 L / min, and spray gun speed 300 mm / s. The second adhesive layer material is NiCrAlY with a particle size of 100 µm and a thickness of 50 µm.

[0059] 3) Allow the adhesive layer sprayed in step 2) to stand in the air for 13 minutes;

[0060] 4) Apply a ceramic transition layer using atmospheric plasma spraying on the coating after the initial settling period in step 3). The parameters are: spray gun power 42kW, spray gun distance 140mm, argon and hydrogen flow rates 48L / min and 7L / min respectively, powder feed rate 2L / min, and spray gun speed 600mm / s; the material is Y... 0.5 Ho 0.5 TaO4 and YSZ were mixed in a 1:1 molar ratio, with a particle size of 80µm and a thickness of 100µm. The ceramic layer was coated using supersonic flame spraying with the following process parameters: oxygen pressure 3MPa, propane pressure 0.8MPa, nitrogen pressure 0.6MPa, oxygen flow rate 1300L / h, propane flow rate 1300L / h, nitrogen flow rate 1100L / h, spray gun distance 160mm, powder feed rate 3 / min, and spray gun speed 300mm / s. The material was a 1:1 molar mixture of Gd2Zr2O7 and HoTaO4, with a particle size of 60µm and a thickness of 280µm.

[0061] Example 6

[0062] 1) Use quartz sand with a particle size of 2mm to sandblast the surface of the nickel-based alloy under a pressure of 6 bar;

[0063] 2) Apply the first adhesive layer to the nickel-based alloy after sandblasting in step 1) using vacuum plasma spraying. The parameters are: vacuum degree 10... -6The parameters for the second adhesive layer are as follows: atomization time (ATM), spray gun power (39 kW), spray gun distance (100 mm), argon and hydrogen flow rates (49 L / min and 4 L / min respectively), powder feed rate (2 L / min), and spray gun speed (500 mm / s). The first adhesive layer material is NiCrAlY with a particle size of 90 µm and a thickness of 80 µm. Supersonic flame spraying is used for the second adhesive layer. The parameters are: oxygen pressure 1 MPa, propane pressure 0.4 MPa, nitrogen pressure 0.7 MPa, oxygen flow rate 1100 L / h, propane flow rate 1100 L / h, nitrogen flow rate 1100 L / h, spray gun distance 150 mm, powder feed rate 2 L / min, and spray gun speed 400 mm / s. The second adhesive layer material is NiCoCrAlYTa with a particle size of 100 µm and a thickness of 70 µm.

[0064] 3) Allow the adhesive layer sprayed in step 2) to stand in the air for 12 minutes;

[0065] 4) Apply a ceramic transition layer using atmospheric plasma spraying on the coating after the initial settling period in step 3). The parameters are: spray gun power 41kW, spray gun distance 110mm, argon and hydrogen flow rates 49L / min and 5L / min respectively, powder feed rate 3L / min, and spray gun speed 800mm / s; the material is Y... 0.5 Ho 0.5 TaO4 and Gd2Zr2O7 were mixed in a 1:1 molar ratio, with a particle size of 80µm and a thickness of 100µm. The ceramic layer was coated using supersonic flame spraying, with the following process parameters: oxygen pressure 3MPa, propane pressure 0.8MPa, nitrogen pressure 0.6MPa, oxygen flow rate 1300L / h, propane flow rate 1300L / h, nitrogen flow rate 1100L / h, spray gun distance 180mm, powder feed rate 2 / min, and spray gun speed 400mm / s. The material was Y... 0.5 Gd 0.5 TaO4 and YSZ were mixed in a 1:1 molar ratio, with a particle size of 60µm and a thickness of 280µm.

[0066] Comparative Example 1

[0067] The difference from Example 1 is that both the first adhesive layer and the second adhesive layer are coated using vacuum plasma spraying.

[0068] Comparative Example 2

[0069] The difference from Example 1 is that both the first and second adhesive layers are coated with supersonic flame.

[0070] Comparative Example 3

[0071] The difference from Example 1 is that both the first adhesive layer and the second adhesive layer are coated with atmospheric plasma.

[0072] Comparative Example 4

[0073] The difference from Example 1 is that the ceramic transition layer material is YTaO4 and the ceramic layer material is Gd2Zr2O7.

[0074] Comparative Example 5

[0075] The difference from Example 1 is that the ceramic transition layer material is YSZ, and the ceramic layer material is Y 0.5 Gd 0.5 TaO4.

[0076] Comparative Example 6

[0077] The difference from Example 1 is that Y 0.5 Gd 0.5 TaO4 and Gd2Zr2O7 were mixed in a molar ratio of 4:1.

[0078] Comparative Example 7

[0079] The difference from Example 1 is that vacuum plasma spraying of metal Ta is used as the first adhesive layer, Ta2O5 is used as the second adhesive layer, atmospheric plasma spraying of YTaO4 is used as the ceramic layer transition layer, and Y3TaO7 is used as the ceramic layer.

[0080] Experimental Example

[0081] 1. XRD characterization:

[0082] The coatings obtained in Examples 1-6 and Comparative Examples 1-7 were examined using X-ray diffraction. Taking the coating obtained in Example 3 as an example, its XRD pattern is as follows: Figure 2 As shown, the XRD test results of Example 3 show that the RETaO4 of phase t and the ZrO2 of phase t are mixed without segregation.

[0083] 2. SEM characterization:

[0084] The coating surfaces obtained in Examples 1-6 and Comparative Examples 1-7 were examined using scanning electron microscopy. Taking the coating obtained in Example 3 as an example, its SEM image is as follows: Figure 3 As shown, according to Figure 3 The powder material is observed to be uniformly melted, with some microcracks on the surface. These microcracks can alleviate the thermal stress caused by thermal expansion and improve the thermal shock resistance.

[0085] 3. Measurement of thermal insulation and cooling gradient

[0086] After preparing coatings for Examples 1-6 and Comparative Examples 1-7 on the surface of nickel-based alloy discs with a diameter of 25.4 mm, the thermal insulation and cooling gradients were tested. The coating surface was heated to 1500℃ within 20 seconds using an acetylene + oxygen spray gun, and the coating surface temperature (T1=1500℃) was measured using an infrared meter. The temperature was held at 1500℃ for 30 seconds, and the back temperature of the nickel-based alloy was measured using a thermocouple (T2). The difference between T1 and T2 is the thermal insulation and cooling gradient of the coating (ΔT=T1-T2). Each sample coating was tested 20 times and the average value was taken.

[0087] Results: As shown in Table 1, the thermal barrier coatings prepared in Examples 1 to 6 have significantly higher thermal insulation and cooling gradients than those in Comparative Examples 1 to 7.

[0088] Table 1 shows the thermal insulation and cooling gradients of Examples 1-6 and Comparative Examples 1-7.

[0089]

[0090] 4. Thermal shock performance testing

[0091] The thermal shock resistance of the samples was tested after coatings of Examples 1-6 and Comparative Examples 1-7 were prepared on the surface of nickel-based alloy discs with a diameter of 25.4 mm. The samples were placed in a tube furnace at 1200 °C for 10 min, then removed and cooled in room temperature water, and then placed back into the tube furnace for one cycle. The coating was considered to have failed when the area of ​​peeling off the surface coating exceeded 10% of the total area.

[0092] Results: As shown in Table 2, the number of thermal shock cycles in Examples 1 to 6 was significantly better than that in Comparative Examples 1 to 7, with Example 3 having as many as 374 thermal shock cycles.

[0093] Table 2. Number of thermal shock cycles for Examples 1-6 and Comparative Examples 1-7

[0094]

[0095] The above descriptions are merely embodiments of the present invention, and common knowledge regarding specific structures and characteristics is not elaborated upon here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A high-temperature resistant and thermal shock resistant thermal barrier coating for nickel-based alloy surfaces, characterized in that, From bottom to top, it consists of a first adhesive layer, a second adhesive layer, a ceramic transition layer, and a ceramic layer; The first adhesive layer and the second adhesive layer are made of one of NiCoCrAlY, NiCrAlY or NiCoCrAlYTa. The thickness of the first adhesive layer is 70 to 80 µm and the thickness of the second adhesive layer is 50 to 70 µm. The first adhesive layer is prepared by vacuum plasma spraying and the second adhesive layer is prepared by supersonic flame spraying. The ceramic transition layer and the ceramic layer are composed of RETaO4 and one of YSZ and Gd2Zr2O7, respectively, wherein RE is one or more of Y, Gd, and Ho; the molar ratio of RETaO4 to YSZ or Gd2Zr2O7 is 1~3:1; the ceramic transition layer and the ceramic layer have different ratios of RETaO4 to YSZ or Gd2Zr2O7. The thickness of the ceramic transition layer is 100 ~ 120µm, and the thickness of the ceramic layer is 200 ~ 320µm.

2. The high-temperature resistant and thermal shock resistant thermal barrier coating on the surface of the nickel-based alloy according to claim 1, characterized in that, The thermal barrier coating has a maximum insulation temperature of 437°C at 1500°C; the thermal shock resistance of the thermal barrier coating is: after holding at 1200°C for 10 minutes, the maximum number of water quenching cycles is 347.

3. The high-temperature resistant and thermal shock resistant thermal barrier coating on the surface of the nickel-based alloy according to claim 1, characterized in that, The particle size of NiCoCrAlY, NiCrAlY, or NiCoCrAlYTa is 90-120µm; the particle size of YSZ, RETaO4, or Gd2Zr2O7 is 45-90µm.

4. The high-temperature resistant and thermal shock resistant thermal barrier coating on the surface of the nickel-based alloy according to claim 1, characterized in that, The first adhesive layer material is NiCoCrAlY, and the second adhesive layer material is NiCoCrAlYTa.

5. The method for preparing the high-temperature resistant and thermal shock resistant thermal barrier coating on the surface of the nickel-based alloy as described in claim 1, characterized in that, Follow these steps to achieve the following: 1) Sandblast the surface of the nickel-based alloy; 2) The first and second bonding layers of the sandblasted nickel-based alloy were sprayed sequentially using vacuum plasma spraying and supersonic flame spraying, and then left to stand in the air for 10 to 15 minutes. 3) The ceramic transition layer and the ceramic layer were sprayed sequentially using atmospheric plasma and supersonic flame spraying, respectively.

6. The method for preparing a high-temperature resistant and thermal shock resistant thermal barrier coating on a nickel-based alloy surface according to claim 5, characterized in that, In step 2), the vacuum plasma spraying process parameters are: vacuum degree is 10. -4 ~ 10 -6 The parameters are as follows: atm, spray gun power is 34 ~ 39kW, spray gun distance is 80 ~ 100 mm, argon and hydrogen gas flow rates are 40 ~ 50L / min and 3 ~ 7L / min respectively, powder feeding rate is 1 ~ 5L / min, and spray gun speed is 400 ~ 800mm / s.

7. The method for preparing a high-temperature resistant and thermal shock resistant thermal barrier coating on a nickel-based alloy surface according to claim 5, characterized in that, In step 2), the supersonic flame spraying process parameters are as follows: oxygen pressure is 1 ~ 2 MPa, propane pressure is 0.3 ~ 0.7 MPa, nitrogen pressure is 0.5 ~ 0.7 MPa, oxygen flow rate is 1000 ~ 1250 L / h, propane flow rate is 1100 ~ 1200 L / h, nitrogen flow rate is 1000 ~ 1100 L / h, spray gun distance is 120 ~ 150 mm, powder feeding rate is 1 ~ 5 L / min, and spray gun speed is 300 ~ 500 mm / s.

8. The method for preparing a high-temperature resistant and thermal shock resistant thermal barrier coating on a nickel-based alloy surface according to claim 5, characterized in that, In step 3), the atmospheric plasma spraying process parameters are as follows: the spray gun power is 40~45kW, the spray gun distance is 120~150 mm, the argon and hydrogen gas flow rates are 45~50L / min and 4~8L / min respectively, the powder feeding rate is 1~5L / min, and the spray gun speed is 400~800mm / s.

9. The method for preparing a high-temperature resistant and thermal shock resistant thermal barrier coating on a nickel-based alloy surface according to claim 5, characterized in that, In step 3), the supersonic flame spraying process parameters are as follows: oxygen pressure is 2 ~ 3 MPa, propane pressure is 0.5 ~ 1 MPa, nitrogen pressure is 0.5 ~ 0.7 MPa, oxygen flow rate is 1200 ~ 1350 L / h, propane flow rate is 1200 ~ 1400 L / h, nitrogen flow rate is 1000 ~ 1100 L / h, spray gun distance is 150 ~ 180 mm, powder feeding rate is 1 ~ 5 L / min, and spray gun speed is 200 ~ 400 mm / s.

10. The method for preparing a high-temperature resistant and thermal shock resistant thermal barrier coating on a nickel-based alloy surface according to claim 5, characterized in that, In step 1), the material used for sandblasting is quartz sand with a particle size of 1 to 2 mm, and the pressure is 3 to 6 bar.

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