Anti-ablation cross-scale composite film layer and magnetron sputtering-plasma spraying synergistic preparation method and application

Abstract

This invention discloses an anti-ablation multi-scale composite film and a method for its synergistic preparation and application using magnetron sputtering and plasma spraying. Belonging to the field of surface engineering and thermal protective coating technology, the method includes: pretreating a resin substrate; depositing a continuous and dense metal-based thin film on the pretreated resin substrate surface using magnetron sputtering at a temperature below the resin substrate's heat distortion temperature to form an interface transition layer; and depositing an anti-plasma ablation functional layer using plasma spraying on the interface transition layer, with the resin substrate temperature not exceeding 150°C during the spraying process, resulting in an anti-ablation multi-scale composite film formed on the resin substrate surface. This invention utilizes low-temperature deposition of a dense transition layer via magnetron sputtering combined with efficient preparation of the anti-ablation functional layer via plasma spraying, avoiding thermal damage to the resin substrate. The composite film exhibits a bonding strength ≥40 MPa and a mass ablation rate <5 mg / s after 500 ablation cycles, demonstrating high reliability under high-temperature conditions and suitability for high-temperature surface protection of various resin substrate materials.

Description

Technical Field

[0001] This invention belongs to the field of surface engineering and thermal protection coating technology, specifically relating to the ablation-resistant multi-scale composite film layer and the synergistic preparation method and application of magnetron sputtering-plasma spraying. Background Technology

[0002] With the rapid development of aerospace, hypersonic vehicles, and plasma propulsion, the surface protection of lightweight structural materials in extreme thermal environments faces severe challenges. Resins and resin-based composites, due to their low density, high specific strength, and ease of processing, are widely used in aircraft structural components, thermal insulation components, and functional load-bearing parts. However, under service environments such as high-temperature aerodynamic heat flux, plasma erosion, and strong thermal shock, resin-based materials have limited temperature resistance and are prone to thermal softening, decomposition, or interface failure, thus limiting their long-term reliable application under high heat flux density conditions. To improve the service capability of resin-based materials in extreme thermal environments, preparing high-temperature resistant and plasma ablation-resistant protective coatings on their surfaces is an effective technical approach. Existing research shows that ceramic materials such as alumina and zirconia have excellent high-temperature resistance and ablation resistance, and using them as protective coatings can significantly improve the temperature resistance of the substrate. However, due to the low heat distortion temperature and poor thermal stability of resin matrices, traditional high-temperature preparation processes cannot directly form dense, stable, and high-bonding high-temperature resistant coatings on their surfaces. Currently, the main methods for preparing coatings on resin-based substrates include sol-gel, brush coating, low-temperature curing, or cold spraying. While these methods can avoid thermal damage to the substrate to some extent, the resulting coatings generally suffer from low density, insufficient ablation resistance, and poor service stability, making it difficult to meet the long-term protection requirements under high heat flux density and plasma ablation environments.

[0003] Chinese patent application CN120041828A discloses a method for preparing a PVD composite coating. It employs a combination of magnetron sputtering and plasma spraying to alternately deposit rare-earth-doped high-entropy alloy coatings and gradient-content composite ceramic coatings on a metal substrate surface. A honeycomb microstructure is then formed through laser texturing, followed by annealing (800-900℃) and hot isostatic pressing (900-950℃) to obtain a multilayer composite coating. This method targets metal substrates (such as cutting tools and molds), but the annealing and hot isostatic pressing processes involve temperatures as high as 800-950℃, making it unsuitable for resin substrates with lower heat distortion temperatures (≤350℃). The coating system is complex (multilayer alternation, laser texturing, etc.), resulting in a long preparation cycle and high cost. Furthermore, its primary purpose is to improve hardness and strength, without addressing the protection of the resin substrate under plasma ablation conditions. It also fails to solve the technical challenge of thermal damage and interfacial delamination of the resin substrate during high-temperature coating preparation due to its thermal sensitivity. Chinese patent application CN120818799A discloses a method for preparing high-performance multilayer coatings based on magnetron sputtering technology. The method involves sequentially depositing a transition layer (Ti), a functional layer (CrAlN), and a protective layer (Al2O3) on the surface of a substrate (including metal, ceramic, or polymer materials). After each layer is deposited, it undergoes Ar ion bombardment for cleaning and activation, followed by low-temperature annealing at 200-400℃. However, this method relies solely on magnetron sputtering, resulting in a low deposition rate and difficulty in preparing a thick, high-temperature resistant protective layer within a reasonable timeframe (its protective layer thickness is only 500 nm-1 μm), limiting its resistance to plasma ablation. While the substrate may include polymers, the method does not propose effective thermal management measures to address the thermal damage to the resin matrix under high-temperature plasma jet erosion, nor does it address the synergy between plasma spraying and magnetron sputtering. Furthermore, the thermal expansion coefficients of the functional layer (CrAlN) and the protective layer (Al2O3) differ significantly from those of the resin matrix, still posing risks of interfacial stress concentration and coating cracking.

[0004] In contrast, plasma spraying technology offers advantages such as high deposition efficiency, strong material adaptability, and the ability to efficiently prepare thick ceramic coatings, making it significantly superior in the field of high-temperature protection. However, the high-temperature plasma jet and high-speed molten particles generated during plasma spraying can cause severe thermal shock and damage to low-temperature resistant resin substrates, easily leading to substrate deformation, decomposition, and even interfacial peeling, making it difficult for the coating to adhere stably. Magnetron sputtering, as a typical physical vapor deposition method, has advantages such as low deposition temperature, high film density, good film uniformity, and strong adhesion to the substrate, making it significantly superior in the preparation of thin films on low-temperature resistant substrate surfaces. However, limited by deposition rate and process characteristics, magnetron sputtering methods are usually difficult to prepare thick high-temperature resistant protective layers within a reasonable time, and the long-term protective capability of a single sputtered film in high heat flux density and plasma ablation environments is also limited. In addition, there are significant differences between resin substrates and high-temperature resistant ceramic coatings in terms of coefficient of thermal expansion, elastic modulus, and thermal conductivity. Direct deposition of ceramic coatings can easily generate large residual thermal stress and stress concentration at the interface, leading to coating cracking or peeling. While existing technologies offer solutions to improve interfacial bonding performance by increasing roughness or introducing simple transition layers, most struggle to achieve an effective balance between low-temperature preparation conditions, interfacial bonding strength, and high-temperature ablation resistance. Especially under repeated plasma erosion or thermal cycling conditions, coating stability remains insufficient. In conclusion, constructing a coating structure that combines high interfacial bonding strength, excellent high-temperature resistance, and plasma ablation resistance while ensuring no thermal damage to the resin matrix remains a critical technical challenge that urgently needs to be addressed in the field of resin matrix surface protection. Summary of the Invention

[0005] In order to overcome the shortcomings of the prior art, the present invention aims to provide a method and application for the preparation of ablation-resistant cross-scale composite films and magnetron sputtering-plasma spraying, so as to solve the technical problem that the existing low-temperature preparation process is difficult to impart high ablation resistance to the resin matrix, while the high-temperature process is prone to inducing irreversible thermal damage to the matrix.

[0006] To achieve the above objectives, the present invention employs the following technical solution: This invention discloses a method for preparing an anti-ablation multi-scale composite film using magnetron sputtering and plasma spraying, comprising: pretreating a resin substrate; depositing a continuous and dense metal-based thin film on the surface of the pretreated resin substrate by magnetron sputtering under conditions below the heat distortion temperature of the resin substrate to form an interface transition layer; and depositing an anti-plasma ablation functional layer by plasma spraying using the interface transition layer as a substrate, wherein the temperature of the resin substrate during the spraying process does not exceed 150°C, thereby obtaining an anti-ablation multi-scale composite film formed on the surface of the resin substrate.

[0007] Preferably, the pretreatment includes roughening the surface of the resin matrix by sandblasting, laser etching and chemical roughening, followed by ultrasonic cleaning of the surface of the resin matrix with anhydrous ethanol for 90-120 s; the resin matrix is ​​a resin or resin-based composite material with a heat distortion temperature not higher than 350 ℃.

[0008] Preferably, the material of the interface transition layer is at least one of Ti, Cr, Al, TiO2 and CrN, and the thickness of the interface transition layer is 1-4 μm.

[0009] Preferably, the process parameters for magnetron sputtering include: sputtering power of 0.5-2.0 kW, working pressure of 0.3-0.8 Pa, argon flow rate of 60-150 sccm, and deposition time of 60-150 min; the temperature of the resin matrix during deposition does not exceed 120℃.

[0010] Preferably, the material of the anti-plasma ablation functional layer is at least one of titanium oxide, aluminum oxide, zirconium oxide, yttrium-stabilized zirconium oxide and silicon carbide, with a particle size of 10-45 μm; the thickness of the anti-plasma ablation functional layer is 200-500 μm.

[0011] Preferably, the anti-plasma ablation functional layer is a single-layer structure, a multi-layer structure, or a gradient structure.

[0012] Preferably, the process parameters for plasma spraying include: argon gas flow rate of 60-150 L·min. -1 The hydrogen flow rate is 10-15 L·min -1 The current is 400-500 A, the voltage is 80-100 V, the spraying distance is 100-180 mm, and the moving speed of the spray gun relative to the substrate is not less than 4000 mm / s. During the spraying process, compressed air is used to cool the back of the substrate so that the substrate temperature does not exceed 150 ℃.

[0013] This invention discloses an ablation-resistant multi-scale composite film, which is prepared by the above-mentioned method of preparing an ablation-resistant multi-scale composite film using magnetron sputtering-plasma spraying synergy.

[0014] Preferably, the ablation-resistant multi-scale composite film includes an interface transition layer disposed on the surface of the resin matrix; and an anti-plasma ablation functional layer disposed outside the interface transition layer; the total bonding strength between the ablation-resistant multi-scale composite film and the resin matrix is ​​not less than 40 MPa, and the mass ablation rate is less than 5 mg / s after undergoing 500 plasma ablation tests.

[0015] This invention discloses the application of the above-mentioned ablation-resistant multi-scale composite film in the preparation of aircraft structural components, thermal insulation components and functional load-bearing components.

[0016] Compared with the prior art, the present invention has the following beneficial effects: This invention discloses a method for the synergistic preparation of ablation-resistant multi-scale composite films using magnetron sputtering and plasma spraying. During magnetron sputtering, a substrate cooling system controls the substrate temperature below its heat distortion temperature, preventing thermal softening or decomposition of the resin substrate during the interface layer preparation stage. During plasma spraying, the substrate temperature is kept below 150°C by adjusting the spray gun movement speed and using compressed air cooling on the back side. Simultaneously, the interface transition layer acts as a thermal barrier, further mitigating the instantaneous thermal shock of the high-temperature jet to the resin substrate. This solves the technical contradiction of carbonization and deformation of the resin substrate due to excessive heat input while achieving thick ceramic coating deposition. The metal-based thin film deposited by magnetron sputtering has a continuous and dense structure, which can closely adhere to the roughened resin substrate surface. On the one hand, it fills microscopic defects and inhibits the formation of interfacial micropores and weak bonding regions; on the other hand, it acts as a property buffer layer, significantly reducing residual thermal stress and stress concentration at the interface between the resin substrate and the ceramic functional layer caused by the large difference in thermal expansion coefficients and elastic moduli, preventing cracking or peeling of the coating due to stress mismatch during preparation or service. Magnetron sputtering contributes a micron-scale dense transition layer, providing a substrate with high bonding strength and thermal protection; plasma spraying contributes a sub-millimeter-scale ablation-resistant functional layer, providing high-temperature resistance and plasma erosion resistance as the main protective layer. The two processes complement each other in scale and function, achieving cross-scale structural optimization of "dense thin layer + thick layer protection." Test results from Examples 1-7 show that the total bonding strength between the composite film prepared by this method and the resin matrix is ​​no less than 40 MPa, far exceeding the bonding strength of the coating obtained by direct plasma spraying (without a transition layer) in Comparative Example 1 (only 5 MPa). After 500 plasma ablation tests, the mass ablation rate of Examples 1-7 is less than 5 mg / s, while the mass ablation rate of Comparative Example 1 is as high as 10 mg / s, indicating that the composite film prepared by this method effectively improves the ablation resistance. Comparative Example 1 also revealed problems such as thermal decomposition and carbonization of the resin substrate surface, and microcracks and pores in the coating caused by direct plasma spraying. In contrast, the composite film layers of Examples 1-7 showed good surface integrity, with no large-area cracking or peeling. The synergistic preparation method of this invention significantly improves the interfacial bonding strength and plasma ablation resistance while ensuring that the resin substrate does not suffer thermal damage, achieving stable preparation of high-temperature protective coatings on the resin substrate surface. By constructing a composite system of a dense interfacial transition layer and a plasma ablation resistance functional layer on the resin substrate surface, the coating system achieves a synergistic improvement in interfacial bonding strength, high-temperature resistance, and plasma ablation resistance while ensuring that the resin substrate does not suffer thermal damage, thereby significantly improving the service reliability and service life of the resin substrate under extreme thermal environments.

[0017] This invention discloses an anti-ablation multi-scale composite film with a three-layer gradient structure: a resin matrix, a magnetron sputtered dense interface transition layer, and a plasma-sprayed anti-ablation functional layer. The interface transition layer forms a strong mechanical and chemical bond with the roughened resin matrix. Simultaneously, the thermal expansion coefficient of the interface transition layer material is between that of the resin matrix and the ceramic functional layer, acting as a "gradient buffer layer" to progressively transfer and disperse thermal stress, preventing stress concentration at a single interface. This structural design results in a total bonding strength between the composite film and the resin matrix of no less than 40 MPa, significantly higher than the 5 MPa of Comparative Example 1. Test data shows that even when the resin matrix's heat distortion temperature is as low as 200 °C (Example 2), the bonding strength still reaches over 40 MPa, demonstrating the broad applicability and stable bonding performance of this film structure to different resin matrices. In the composite film, the magnetron sputtering transition layer has a thickness on the micrometer scale but extremely high density, effectively preventing active particles in the plasma jet from penetrating to the resin matrix interface. The plasma-sprayed functional layer has a thickness on the sub-millimeter scale, belonging to a thick ceramic coating, capable of withstanding the high heat flux density of plasma erosion. The dense thin layer ensures interface stability, while the thick ceramic layer provides a physical barrier and a primary heat dissipation component. After 500 plasma ablation tests, Examples 1-7 showed a mass ablation rate of less than 5 mg / s (minimum 3.8 mg / s), while Comparative Example 1 (without the transition layer) had a mass ablation rate as high as 10 mg / s. This indicates that the gradient structure of this composite film effectively suppresses cracking, delamination, or peeling caused by thermal shock and stress concentration during ablation, thereby significantly reducing the mass ablation rate. Figure 5 and Figure 6 The comparison diagrams shown intuitively demonstrate that the bonding strength of Examples 1-7 is effectively improved and the ablation rate is effectively reduced compared to Comparative Example 1. Figure 4 The scanning electron microscope morphology comparison showed that the surface of the substrate without film was severely damaged after ablation, while the surface of the sample with composite film was intact and no large-area cracking or peeling was observed.

[0018] This invention discloses the application of an ablation-resistant multi-scale composite membrane in the fabrication of aircraft structural components, thermal insulation components, and functional load-bearing parts. Aircraft are extremely sensitive to structural weight. Resin-based composite materials are widely used due to their low density and high specific strength, but their temperature resistance is limited. The composite membrane of this invention provides a thick ceramic protection layer with a bonding strength of no less than 40 MPa on the surface of the resin matrix, enabling resin-based structural components to withstand the intense aerodynamic heat flow and plasma sheath erosion generated during hypersonic flight. High-temperature ablation resistance is imparted solely through a surface coating, achieving the engineering goal of "lightweight structure + high-efficiency protection." After 500 plasma ablation tests, the mass ablation rate is less than 5 mg / s, indicating that the membrane can maintain structural integrity under repeated use or long-term service conditions. This is of significant value for the protection of structural components in reusable aircraft. Aircraft thermal insulation components need to withstand high-temperature heat flow and prevent heat transfer to the internal structure. The plasma-sprayed ablation-resistant functional layer in the composite film of this invention uses a low thermal conductivity material, which can effectively reflect and dissipate incident heat flow. Simultaneously, the dense magnetron sputtering transition layer acts as an additional thermal barrier, further reducing heat conduction at the interface. This double-layer thermal barrier structure enables the resin-based thermal insulation component to achieve excellent resistance to plasma erosion while maintaining low thermal conductivity. Example 3, using a YSZ functional layer (250 μm thick), showed a mass ablation rate of only 4.2 mg / s after 500 ablation cycles, demonstrating the reliability of this film layer in thermal insulation applications. Functional load-bearing components simultaneously endure high temperatures, plasma corrosion, thermal cycling fatigue, and mechanical loads during service. The gradient structure of the composite film of this invention can cope with this multi-physics coupled environment: the outer ablation-resistant functional layer directly resists the high-temperature erosion and chemical corrosion of the plasma jet; the middle dense transition layer prevents oxidizing atmospheres from penetrating to the resin interface, preventing matrix carbonization failure; and the stress buffering effect of the transition layer makes the film layer less prone to fatigue cracking under thermal cycling conditions. Example 5 uses a SiC functional layer (285 μm thick), with a bonding strength of 42.8 MPa and an ablation rate of 4 mg / s. SiC has extremely high hardness and excellent thermal stability, making it particularly suitable for extreme working conditions with high loads and strong erosion. Example 4 uses a TiO2 / ZrO2 / YSZ gradient structure functional layer, with an ablation rate as low as 3.8 mg / s, demonstrating the performance advantages of multi-layer gradient design under complex working conditions. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the bonding strength test of the ablation-resistant cross-scale composite film layer disclosed in this invention; Figure 2 This is a schematic diagram of the plasma jet ablation experiment disclosed in this invention; Figure 3The images shown are scanning electron microscope images of the surface and cross-section of the ablation-resistant multi-scale composite film prepared in Example 1 of the present invention; wherein, (a) is the low-magnification morphology of the cross-section of the ablation-resistant multi-scale composite film, (b) is the high-magnification morphology of the cross-section of the ablation-resistant multi-scale composite film, and (c) is the surface morphology of the ablation-resistant multi-scale composite film. Figure 4 The images show the surface morphology of the substrate without a film layer after ablation and the surface morphology of the sample with ablation-resistant multi-scale composite film layer after ablation, as prepared in Example 1 of this invention; wherein, (a) is the surface morphology of the resin substrate without a film layer after ablation, and (b) is the surface morphology of the sample with ablation-resistant multi-scale composite film layer after ablation. Figure 5 The image shows a comparison of the bonding strength between the ablation-resistant multi-scale composite film prepared in Examples 1-7 of this invention and the TiO2 coating prepared in Comparative Example 1. Figure 6 The changes in mass ablation rate of the ablation-resistant multi-scale composite films prepared in Examples 1-7 of this invention and the TiO2 coating prepared in Comparative Example 1 before and after ablation are shown.

[0020] Among them, 1. stretching mating parts; 2. adhesive film; 3. substrate; 4. composite film layer; 5. stretching screw; 6. robotic arm; 7. plasma spray gun; 8. plasma jet. Detailed Implementation

[0021] The technical solution of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] Unless otherwise specified, all embodiments and preferred embodiments mentioned herein can be combined to form new technical solutions.

[0023] Unless otherwise specified, all the technical features and preferred features mentioned herein can be combined to form new technical solutions.

[0024] In this invention, unless otherwise specified, percentage (%) or parts refer to weight percentage or parts relative to the composition.

[0025] Unless otherwise specified, the components or preferred components involved in this invention can be combined with each other to form new technical solutions.

[0026] In this invention, unless otherwise specified, the numerical range "a~b" is an abbreviation for any combination of real numbers between a and b, where a and b are real numbers. For example, the numerical range "6~22" indicates that all real numbers between "6~22" have been listed in this document, and "6~22" is simply an abbreviation for these numerical combinations.

[0027] The "scope" disclosed in this invention can be in the form of a lower limit and an upper limit, and can be one or more lower limits and one or more upper limits, respectively.

[0028] The term “and / or” as used in this invention refers to any combination of one or more of the associated listed items, as well as all possible combinations, and includes such combinations.

[0029] Unless otherwise stated, the technical and scientific terms used herein have the same meanings as those familiar to those skilled in the art. Furthermore, any methods or materials similar to or equivalent to those described herein may also be used in this invention.

[0030] This invention provides a method for preparing an anti-ablation multi-scale composite film using magnetron sputtering and plasma spraying. The preparation method combines magnetron sputtering and plasma spraying processes. First, a dense interfacial transition layer is deposited at low temperature on the surface of a resin substrate using magnetron sputtering. Then, an anti-plasma ablation functional layer is efficiently deposited on the transition layer using plasma spraying. This results in a composite film with both high interfacial bonding strength and excellent high-temperature resistance to plasma ablation on the surface of a low-temperature resistant resin substrate.

[0031] By controlling the substrate temperature during magnetron sputtering deposition to be lower than the heat distortion temperature of the resin substrate, thermal damage to the substrate can be avoided. At the same time, during plasma spraying, by adjusting the spraying parameters and combining them with substrate cooling measures, the heat input per unit area can be reduced, thereby achieving stable deposition of a thick ablation-resistant functional layer without damaging the resin substrate.

[0032] This invention provides a method for preparing ablation-resistant multi-scale composite films using magnetron sputtering and plasma spraying, specifically comprising the following steps: (1) Matrix pretreatment: The surface of the resin matrix is ​​cleaned and roughened to remove surface contaminants and improve surface roughness and interfacial mechanical interlocking.

[0033] In order to increase the mechanical interlocking points on the substrate surface and remove surface contaminants, the resin substrate surface needs to be roughened. Substrate pretreatment includes at least one roughening treatment among sandblasting, laser etching, and chemical roughening of the resin substrate surface.

[0034] If sandblasting is used, 120-200 mesh white or brown fused alumina is preferred, with a sandblasting pressure of 0.2-0.4 MPa. If laser etching is used, the laser energy density must be controlled to avoid excessive carbonization of the substrate.

[0035] After the roughening treatment is completed, the surface of the resin matrix is ​​ultrasonically cleaned with anhydrous ethanol for 90-120 seconds to thoroughly remove residual sand particles and oil stains.

[0036] The resin matrix is ​​a resin or resin-based composite material with a heat distortion temperature not exceeding 350 ℃.

[0037] (2) Magnetron sputtering deposition of the interface transition layer: The pretreated substrate is placed in a magnetron sputtering vacuum chamber. During the deposition process, the substrate cooling system (water-cooled substrate) must be turned on to strictly control the substrate temperature below its heat distortion temperature, and not exceed 120 °C, in order to prevent thermal damage or deformation of the resin substrate.

[0038] Under the condition that the substrate temperature is controlled to be lower than its heat distortion temperature, a continuous and dense thin film is deposited on the surface of the pretreated resin substrate by magnetron sputtering to form an interface transition layer.

[0039] The material of the interface transition layer is at least one of metals (such as Ti, Cr, Al, etc.), metal oxides (such as TiO2, etc.) and metal nitrides (such as CrN, etc.), and the thickness of the interface transition layer is 1-4 μm, which is in the micrometer range.

[0040] The interface transition layer not only serves as physical insulation, but also acts as a "base layer" to significantly improve the adhesion of subsequent coatings.

[0041] The process parameters for magnetron sputtering include: sputtering power of 0.5-2.0 kW, working pressure of 0.3-0.8 Pa, argon flow rate of 60-150 sccm, and deposition time of 60-150 min. While ensuring continuous and dense film, the substrate temperature is controlled to not exceed 120 ℃ during the deposition process by using a substrate cooling system.

[0042] (3) Plasma spraying deposition of ablation-resistant functional layer: Using the interface transition layer as a substrate, a thick anti-plasma ablation functional layer is deposited by wide-velocity high-energy plasma spraying, thereby obtaining an anti-ablation multi-scale composite film layer formed on the surface of the resin matrix.

[0043] The ablation-resistant multi-scale composite film structure formed by the above preparation method includes a magnetron sputtered dense interface transition layer disposed on the surface of the resin substrate, and a plasma-sprayed ablation-resistant functional layer disposed outside the interface transition layer. The total bonding strength between the ablation-resistant multi-scale composite film and the resin substrate is not less than 40 MPa, and the mass ablation rate is less than 5 mg / s after undergoing 500 plasma ablation tests.

[0044] The anti-plasma ablation functional layer is made of at least one of titanium oxide, aluminum oxide, zirconium oxide, yttrium-stabilized zirconium oxide (YSZ), and silicon carbide. The powder particle size ranges from 10 to 45 μm, and the thickness of the anti-plasma ablation functional layer is 200 to 500 μm, which is in the sub-millimeter range.

[0045] The anti-plasma ablation functional layer can be a single-layer structure, a multi-layer structure (such as an Al2O3 bottom layer + ZrO2 top layer), or a gradient structure.

[0046] To reduce heat input to the substrate, the process parameters for plasma spraying include: argon flow rate of 60-150 L / min. -1 The hydrogen flow rate is 10-15 L·min -1 The current is 400-500 A, the voltage is 80-100 V, and the spraying distance is 100-180 mm. Simultaneously, during the spraying process, the moving speed of the spray gun relative to the substrate is controlled to be no less than 4000 mm / s to reduce heat accumulation in a single scan; compressed air is used to continuously cool the back of the substrate during the spraying process, ensuring that the substrate temperature does not exceed 150 ℃ throughout the entire process.

[0047] This invention innovatively employs a combination of magnetron sputtering and plasma spraying processes to achieve synergistic optimization of a high-temperature resistant submicron-level coating and a highly bonded micron-level thin film on a low-temperature resistant resin substrate. Specifically, it leverages the advantages of magnetron sputtering—dense film formation, controllable temperature, and friendliness to heat-sensitive substrates—while also utilizing plasma spraying's ability to efficiently deposit thick ceramic coatings, significantly improving high-temperature resistance and ablation resistance. Compared to the shortcomings of single-method approaches such as insufficient ablation resistance in thin coatings obtained using only low-temperature coating / sol-gel processes, or the disadvantages of direct plasma spraying leading to thermal damage to the resin substrate and easy interface failure, this invention achieves stable preparation of a high-temperature resistant and plasma ablation-resistant composite film on the resin substrate surface while ensuring the substrate temperature remains below the heat distortion temperature.

[0048] This invention first deposits a continuous and dense interfacial transition layer on the surface of a resin matrix using magnetron sputtering. This significantly improves interfacial bonding strength and reduces interfacial defects and failures. The transition layer film can establish a stable interfacial connection between the resin matrix and the ceramic functional layer. On the one hand, the dense film helps suppress the formation of defects such as interfacial micropores and weak bonding regions, improving interfacial continuity. On the other hand, the transition layer, as a "property buffer layer," can reduce stress concentration caused by differences in thermal expansion coefficients and elastic moduli between the resin matrix and the ceramic functional layer. Therefore, under conditions such as plasma erosion and thermal shock, it can effectively reduce the risk of interfacial failures such as coating cracking, delamination, or peeling, fundamentally improving the reliability of the coating system.

[0049] Through the combined effects of the aforementioned dual-process synergistic preparation and the dense interface transition layer, the plasma ablation resistant composite film prepared in this invention maintains good structural integrity and performance stability under high heat flux density and repeated plasma erosion conditions. The stable bonding relationship formed between the interface transition layer and the ceramic functional layer helps to suppress failure modes such as cracking, delamination, or peeling caused by thermal shock and stress concentration during the ablation process, thereby effectively reducing the mass ablation rate and improving the long-term protection capability and service reliability of the resin matrix under extreme thermal environments.

[0050] This invention offers designability of the interface structure and broad applicability to various substrates. The process described herein is highly flexible and controllable, allowing for the precise construction of interface transition layers with gradual compositional or modulus gradients by adjusting the composition of the magnetron sputtering target (e.g., selecting metals like Cr, Al, or their oxides) and the deposition process, based on the differences in thermophysical properties between different resin matrices (e.g., epoxy, phenolic, polyimide, etc.) and the outer ceramic layer. Simultaneously, the material system and structural form of the anti-plasma ablation functional layer are designable, allowing for the selection of single-layer, multi-layer, or gradient structures according to different protection requirements. Through structural configuration design, the mismatch in thermal expansion coefficients between the resin matrix and the ceramic coating can be minimized, effectively mitigating thermal stress. This makes the preparation method widely applicable to high-temperature surface protection of various heat-sensitive resin-based composite materials. Therefore, this invention not only provides a coating preparation method but also offers structural design flexibility for different operating conditions, demonstrating significant engineering application value.

[0051] This invention successfully resolves the technical challenge of heat-sensitive resin matrices directly withstanding high-temperature thermal spraying through a step-by-step synergistic process: "matrix micro-coating - low-temperature dense undercoating by magnetron sputtering - thick-layer protection by plasma spraying." Specifically, the substrate pretreatment increases mechanical bonding points; the dense transition layer formed by magnetron sputtering at low temperatures not only acts as a "thermal barrier" to prevent oxidation and carbonization of the resin during subsequent high-temperature preparation, but also serves as a "stress buffer layer" and a "bonding bridge," effectively mitigating the mismatch in thermal expansion coefficients between the resin matrix and the upper ceramic coating; and the outer plasma spraying layer fully utilizes its high-temperature resistance and ablation resistance physical protective properties. This gradient protection structure from the inside out ensures that the coating system maintains structural integrity under extreme thermal shock environments, achieving a dual improvement in coating bonding strength and ablation resistance.

[0052] The ablation-resistant multi-scale composite film prepared by this embodiment is a high-bonding-strength, plasma-resistant multi-scale composite film on the resin matrix surface. From the inside out, it forms a bonding system of "resin matrix - dense interface transition layer - porous ablation-resistant functional layer". Testing and verification show that this process significantly improves the interfacial bonding force (bonding strength not less than 40 MPa) while ensuring no thermal damage to the resin matrix, and endows the matrix with excellent high-temperature ablation resistance (mass ablation rate less than 5 mg / s). This method has a wide process window and strong controllability, enabling the stable preparation of high-performance protective coatings with extreme service requirements, and has significant engineering application value.

[0053] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0054] Example 1 In this embodiment, a TiO2-TiO2 composite film was prepared on a glass fiber reinforced epoxy resin matrix (heat distortion temperature of about 350 °C).

[0055] (I) Preparation of composite film Glass fiber reinforced epoxy resin was selected as the matrix material, with a heat distortion temperature of approximately 350 ℃. The matrix was processed into experimental specimens of suitable size for the preparation and performance testing of the composite film.

[0056] 1) Matrix pretreatment The substrate surface to be treated is cleaned and roughened. Specifically, the surface of the glass fiber reinforced epoxy resin substrate is first roughened by sandblasting with 150-mesh white corundum abrasive. After sandblasting, the substrate surface is ultrasonically cleaned with anhydrous ethanol for 100 seconds to remove residual dust, contaminants, and weak bonding layers. After cleaning, the substrate is dried.

[0057] The above treatments enable the substrate surface to achieve good cleanliness and appropriate surface roughness, providing stable interface conditions for subsequent coating deposition.

[0058] 2) Magnetron sputtering deposition interface transition layer The pretreated substrate is placed in the vacuum chamber of the magnetron sputtering equipment. After the vacuum is evacuated to the required level, an interface transition layer is deposited on the substrate surface.

[0059] In this embodiment, TiO2 target material is selected as the sputtering target material, and the magnetron sputtering process parameters are set as follows: The sputtering power was 1.0 kW, the working pressure was 0.5 Pa, the argon flow rate was 150 sccm, and the deposition time was 90 min.

[0060] During the sputtering deposition process, the resin matrix is ​​continuously cooled by a matrix cooling system to keep the surface temperature of the matrix below 120 ℃, so as to avoid thermal deformation or thermal damage to the resin matrix.

[0061] Through the above magnetron sputtering process, a continuous and dense TiO2 interface transition layer with a thickness of about 1 μm is formed on the substrate surface. The formed interface transition layer is well bonded to the substrate, and the surface is uniform and without obvious defects.

[0062] 3) Plasma spraying deposition of anti-plasma ablation functional layer After the interface transition layer deposition is completed, the sample is transferred to a plasma spraying equipment to deposit an anti-plasma ablation functional layer using the interface transition layer as a substrate.

[0063] In this embodiment, titanium dioxide (TiO2) ceramic powder is selected as the anti-plasma ablation functional layer material, and a single-layer anti-ablation functional layer is deposited. The powder particle size range is 10-45 μm.

[0064] The plasma spraying process parameters are set as follows: The plasma gas consists of argon and hydrogen, with an argon flow rate of 100 L·min. -1 The hydrogen flow rate is 10 L·min -1 ; The spraying current is 400 A, the spraying voltage is 100 V, and the spraying distance is 150 mm.

[0065] During the spraying process, the moving speed of the spray gun relative to the substrate is controlled at 4000 mm / s, and compressed air is used to continuously cool the back of the substrate, so that the surface temperature of the substrate is always controlled below 150 ℃, thereby reducing the instantaneous heat input during the spraying process.

[0066] Through multiple spraying passes, a TiO2 anti-plasma ablation functional layer with a thickness of approximately 200 μm is formed on the outer side of the interface transition layer.

[0067] Figure 3 The images show scanning electron microscope (SEM) images of the surface and cross-section of the ablation-resistant multi-scale composite film prepared in Example 1 of this invention; wherein, (a) is the low-magnification morphology of the cross-section of the ablation-resistant multi-scale composite film, (b) is the high-magnification morphology of the cross-section of the ablation-resistant multi-scale composite film, and (c) is the surface morphology of the ablation-resistant multi-scale composite film; it can be seen from the images that the surface and cross-section of the composite film are uniform without obvious defects and are tightly bonded to the substrate.

[0068] (II) Performance testing of composite membrane layers The composite film sample prepared in Example 1 was tested for bonding strength and resistance to plasma ablation.

[0069] 1) Combined strength test The strength test was conducted according to GB / T8642-2002 standard, and the coating was prepared on a substrate with a diameter of Ф25.4×4 mm.

[0070] Figure 1 This is a schematic diagram of the cross-scale composite film bonding strength test disclosed in this invention. As shown in the diagram, firstly, the uncoated surface of the substrate 3 and the surface of the tensile mating part 1 are treated with coarse sandblasting. Then, the composite film layer 4 is bonded to the tensile mating part 1 using adhesive film 2, and placed in a fixture, ensuring that the centers of the substrate 3 and the tensile mating part 1 coincide. Subsequently, the fixture containing the test sample is placed in an oven at 185 ℃ for 3 hours to allow the adhesive film 2 to fully cure between the test sample and the tensile mating part 1. The structural schematic diagram is shown below. Figure 1 As shown. After being removed and cooled to room temperature, a universal tensile testing machine was used for testing. Tensile screw 5 was used to connect to the universal tensile testing machine, transferring the tensile force of the machine to the entire test sample assembly, thus achieving a load test on the bonding strength of the composite film layers; the tensile rate was 0.1 mm. min -1 Each sample was tested three times, and the average value was taken. The test results show that the average bonding strength of the composite film layer 4 is 45 MPa.

[0071] 2) Plasma ablation resistance test Figure 2 This is a schematic diagram of the plasma jet ablation experiment disclosed in this invention. The ablation experiment uses a cuboid sample with a composite film layer 4, and the sample is fixed within a groove in a steel plate. The ablation distance between the sample surface and the nozzle tip of the plasma spray gun 7 is 70 mm, and the nozzle inner diameter is 2 mm. The ablation direction is perpendicular to the sample surface. The plasma spray gun 7 generates a plasma jet 8, which, driven by the robotic arm 6, performs unidirectional repeated ablation on the sample from left to right. The mass ablation rate is calculated by measuring the change in sample weight before and after ablation, thereby evaluating the ablation performance of the composite film layer. The calculation formula is as follows:

[0072] in, m loss Mass ablation rate (unit: mg·s) -1 ), m 1 represents the initial weight of the sample. m 2 represents the weight of the sample after ablation. t For time.

[0073] After 500 consecutive plasma ablation cycles, the mass change of the sample was measured, and the results showed that the mass ablation rate of the composite film was 4.5 mg / s.

[0074] Figure 4 The images show the surface morphology of the substrate without a film layer after ablation and the surface morphology of the sample with the ablation-resistant multi-scale composite film layer after ablation, as prepared in Example 1 of this invention. Among them, (a) is the surface morphology of the resin substrate without a film layer after ablation, and (b) is the surface morphology of the sample with the ablation-resistant multi-scale composite film layer after ablation. As can be seen from the figures, the resin substrate without a film layer is severely ablated after 500 ablation cycles, while the surface integrity of the ablation-resistant multi-scale composite film layer is good, and no large-area cracking or peeling occurs.

[0075] Test results show that the composite film prepared in this embodiment maintains high interfacial bonding strength while exhibiting excellent resistance to plasma ablation, thus meeting the protection requirements of the resin matrix in a high-temperature plasma environment.

[0076] Example 2 In this embodiment, a Ti / Al-Al2O3 / ZrO2 composite film was prepared on an epoxy resin matrix (heat distortion temperature of about 200 °C).

[0077] 1) Matrix pretreatment The substrate surface to be treated was cleaned and roughened. 200-mesh brown corundum abrasive was used at a blasting pressure of 0.2 MPa to ensure sufficient surface roughness. Subsequently, the treated substrate surface was ultrasonically cleaned with anhydrous ethanol for 120 seconds, and then dried after cleaning.

[0078] 2) Magnetron sputtering deposition interface transition layer The pretreated substrate is placed in the vacuum chamber of the magnetron sputtering equipment. After the vacuum is evacuated to the required level, an interface transition layer is deposited on the substrate surface using magnetron sputtering.

[0079] In this embodiment, pure Al and pure Ti targets are selected as sputtering targets, and the magnetron sputtering process parameters are set as follows: The sputtering power was 1.5 kW, the working pressure was 0.4 Pa, the argon flow rate was 90 sccm, and the deposition time was 120 min.

[0080] During the sputtering deposition process, the resin matrix is ​​continuously cooled by a matrix cooling system to keep the surface temperature of the matrix below 100 ℃.

[0081] The above magnetron sputtering process forms a Ti / Al interface transition layer on the substrate surface with a thickness of about 2.5 μm. The interface transition layer is well bonded to the substrate, and the surface is uniform and without obvious defects.

[0082] 3) Plasma spraying deposition of anti-plasma ablation functional layer After completing the deposition of the interface transition layer, the anti-plasma ablation functional layer is deposited using the interface transition layer as the substrate.

[0083] Alumina and zirconium oxide powders were selected as anti-plasma ablation functional layer materials, and multiple anti-ablation functional layers were deposited with powder particle size ranging from 10 to 45 μm.

[0084] The plasma spraying process parameters are set as follows: The plasma gas consists of argon and hydrogen, with an argon flow rate of 150 L·min. -1 The hydrogen flow rate is 15 L·min -1 ; The spraying current is 450 A, the spraying voltage is 80 V, and the spraying distance is 180 mm.

[0085] During the spraying process, the moving speed of the spray gun relative to the substrate is controlled at 5000 mm / s, and compressed air is used to continuously cool the back of the substrate, so that the surface temperature of the substrate is always controlled below 120 ℃, thereby reducing the instantaneous heat input during the spraying process.

[0086] Through multiple plasma spraying passes, an Al2O3 / ZrO2 anti-plasma ablation functional layer with a thickness of about 500 μm is formed on the outside of the interface transition layer. The resulting composite film has a uniform surface without obvious defects and is tightly bonded to the substrate.

[0087] Performance testing The interfacial bonding strength between the composite film and the resin matrix was tested, and the test results showed that the bonding strength of the composite film was 40 MPa.

[0088] The samples were subjected to 500 plasma ablation tests. The test results showed that the mass ablation rate of the composite film was 5 mg / s, the surface integrity of the coating was good, and no large-area cracking or peeling occurred.

[0089] Example 3 In this embodiment, a CrN-YSZ composite film was prepared on a polyimide resin matrix (heat distortion temperature of about 250 °C).

[0090] 1) Matrix pretreatment The substrate surface to be treated is cleaned and roughened. The substrate surface is first roughened using laser etching, with the laser energy density set to 0.5 J / mm². 2 The etching time was 3 minutes. Subsequently, the surface was ultrasonically cleaned with anhydrous ethanol for 120 seconds to ensure that the surface was free of contaminants.

[0091] 2) Magnetron sputtering deposition interface transition layer In this embodiment, a CrN target is used for magnetron sputtering, and the magnetron sputtering process parameters are set as follows: The sputtering power was 2 kW, the working pressure was 0.3 Pa, the argon flow rate was 60 sccm, and the deposition time was 150 min.

[0092] During the sputtering deposition process, the resin matrix is ​​continuously cooled by a matrix cooling system to keep the surface temperature of the matrix below 120 ℃.

[0093] The above magnetron sputtering process forms a CrN interface transition layer on the surface of the resin matrix with a thickness of about 4 μm. The interface transition layer is well bonded to the matrix, and the surface is uniform and without obvious defects.

[0094] 3) Plasma spraying deposition of anti-plasma ablation functional layer In this embodiment, yttrium-stabilized zirconia (YSZ) ceramic powder is selected as the anti-plasma ablation functional layer material, and a single-layer anti-ablation functional layer is deposited. The powder particle size range is 10-45 μm.

[0095] The plasma spraying process parameters are set as follows: The plasma gas consists of argon and hydrogen, with an argon flow rate of 120 L / min. -1 The hydrogen flow rate is 12 L·min -1 ; The spraying current is 450 A, the spraying voltage is 85 V, and the spraying distance is 100 mm.

[0096] During the spraying process, the moving speed of the spray gun relative to the substrate is controlled at 5000 mm / s, and compressed air is used to continuously cool the back of the substrate, so that the surface temperature of the substrate is always controlled below 120 ℃, thereby reducing the instantaneous heat input during the spraying process.

[0097] Through multiple plasma spraying passes, a YSZ anti-plasma ablation functional layer with a thickness of about 250 μm is formed on the outside of the interface transition layer. The resulting composite film has a uniform surface without obvious defects and is tightly bonded to the substrate.

[0098] Performance testing The interfacial bonding strength between the composite film and the resin matrix was tested, and the test results showed that the bonding strength of the composite film was 41.6 MPa.

[0099] The samples were subjected to 500 plasma ablation tests. The test results showed that the mass ablation rate of the composite film was 4.2 mg / s, the surface integrity of the coating was good, and no large-area cracking or peeling was observed.

[0100] Example 4 In this embodiment, a Ti-TiO2 / ZrO2 / YSZ composite film was prepared on a phenolic resin matrix (heat distortion temperature of about 250 °C).

[0101] 1) Matrix pretreatment The substrate surface to be treated was cleaned and roughened. The substrate surface was first chemically roughened by immersing it in a sodium hydroxide solution for 3 minutes, followed by rinsing with water and drying in an oven at 50 °C. The surface was then ultrasonically cleaned with anhydrous ethanol for 110 seconds to ensure that the surface was free of contaminants.

[0102] 2) Magnetron sputtering deposition interface transition layer In this embodiment, a Ti target is used for sputtering deposition, and the magnetron sputtering process parameters are set as follows: The sputtering power was 0.5 kW, the working pressure was 0.5 Pa, the argon flow rate was 90 sccm, and the deposition time was 60 min.

[0103] During the sputtering deposition process, the resin matrix is ​​continuously cooled by the matrix cooling system to keep the surface temperature of the matrix below 110 ℃.

[0104] The above magnetron sputtering process forms a Ti interface transition layer on the surface of the resin matrix with a thickness of about 1 μm. The interface transition layer is well bonded to the matrix, and the surface is uniform and without obvious defects.

[0105] 3) Plasma spraying deposition of anti-plasma ablation functional layer After completing the deposition of the interface transition layer, the anti-plasma ablation functional layer is deposited on the interface transition layer as a substrate.

[0106] In this embodiment, titanium oxide (TiO2), zirconium oxide (ZrO2), and yttrium-stabilized zirconium oxide (YSZ) powders are selected as anti-plasma ablation functional layer materials to deposit a gradient anti-ablation functional layer with a powder particle size range of 10-45 μm.

[0107] The plasma spraying process parameters are set as follows: The plasma gas consists of argon and hydrogen, with an argon flow rate of 140 L·min. -1 The hydrogen flow rate is 10 L·min -1 ; The spraying current is 500 A, the spraying voltage is 95 V, and the spraying distance is 170 mm.

[0108] During the spraying process, the moving speed of the spray gun relative to the substrate is controlled to be no less than 5300 mm / s, and compressed air is used to continuously cool the back of the substrate, so that the surface temperature of the substrate is always controlled below 120 ℃, thereby reducing the instantaneous heat input during the spraying process.

[0109] Through multiple plasma spraying passes, a plasma ablation resistant functional layer with a thickness of approximately 280 μm is formed on the outer side of the interface transition layer. The resulting composite film has a uniform surface without obvious defects and is tightly bonded to the substrate.

[0110] Performance testing The interfacial bonding strength between the composite film and the resin matrix was tested, and the test results showed that the bonding strength of the composite film was 42 MPa.

[0111] The samples were subjected to 500 plasma ablation tests. The test results showed that the mass ablation rate of the composite film was 3.8 mg / s, the surface integrity of the coating was good, and no large-area cracking or peeling was observed.

[0112] Example 5 In this embodiment, a Cr / CrN-SiC composite film was prepared on a carbon fiber reinforced epoxy resin matrix (heat distortion temperature of about 350 °C).

[0113] 1) Matrix pretreatment The substrate surface was treated with laser etching, and the laser energy density was set to 0.8 J / mm². 2 The etching time was 3 min. Subsequently, the surface was ultrasonically cleaned with anhydrous ethanol for 120 s, and the substrate was dried after cleaning.

[0114] 2) Magnetron sputtering deposition interface transition layer In this embodiment, a Cr target is used for sputtering deposition: The process parameters for depositing the Cr layer were: sputtering power of 0.8 kW, working pressure of 0.5 Pa, argon flow rate of 95 sccm, and deposition time of 25 min.

[0115] The process parameters for depositing the CrN layer were as follows: sputtering power of 0.8 kW, working pressure of 0.5 Pa, argon flow rate of 95 sccm, nitrogen flow rate of 35 sccm, and deposition time of 85 min.

[0116] The cooling system ensures that the substrate temperature does not exceed 100 °C. After deposition, a gradient transition layer with a thickness of 2.5 μm is obtained. The resulting interface transition layer is well bonded to the substrate and has a uniform surface without obvious defects.

[0117] 3) Plasma spraying deposition of anti-plasma ablation functional layer In this embodiment, silicon carbide (SiC) is selected as the anti-plasma ablation functional layer material, and a single-layer anti-ablation functional layer is deposited with a powder particle size range of 10-45 μm.

[0118] The plasma spraying process parameters are set as follows: The plasma gas consists of argon and hydrogen, with an argon flow rate of 60 L / min. -1 The hydrogen flow rate is 15 L·min -1 ; The spraying current is 500 A, the spraying voltage is 90 V, and the spraying distance is 120 mm.

[0119] During the spraying process, the moving speed of the spray gun relative to the substrate is controlled to be no less than 5000 mm / s, and compressed air is used to continuously cool the back of the substrate, so that the surface temperature of the substrate is always controlled below 150 ℃, thereby reducing the instantaneous heat input during the spraying process.

[0120] Through multiple plasma spraying passes, a plasma ablation resistant functional layer with a thickness of approximately 285 μm is formed on the outer side of the interface transition layer. The resulting composite film has a uniform surface without obvious defects and is tightly bonded to the substrate.

[0121] Performance testing The interfacial bonding strength between the composite film and the resin matrix was tested, and the test results showed that the bonding strength of the composite film was 42.8 MPa.

[0122] The samples were subjected to 500 plasma ablation tests. The test results showed that the mass ablation rate of the composite film was 4 mg / s, the surface integrity of the coating was good, and no large-area cracking or peeling occurred.

[0123] Example 6 In this embodiment, a Ti-ZrO2 composite film was prepared on an epoxy resin matrix (heat distortion temperature of about 200 °C).

[0124] 1) Matrix pretreatment The substrate surface to be treated was cleaned and roughened. 200-mesh brown corundum abrasive was used at a blasting pressure of 0.2 MPa to ensure sufficient surface roughness. Subsequently, the treated substrate surface was ultrasonically cleaned with anhydrous ethanol for 90 seconds, and then dried after cleaning.

[0125] 2) Magnetron sputtering deposition interface transition layer The pretreated substrate is placed in the vacuum chamber of the magnetron sputtering equipment. After the vacuum is evacuated to the required level, an interface transition layer is deposited on the substrate surface using magnetron sputtering.

[0126] In this embodiment, a pure Ti target is selected as the sputtering target, and the magnetron sputtering process parameters are set as follows: The sputtering power was 1.7 kW, the working pressure was 0.8 Pa, the argon flow rate was 100 sccm, and the deposition time was 100 min.

[0127] During the sputtering deposition process, the resin matrix is ​​continuously cooled by a matrix cooling system to keep the surface temperature of the matrix below 100 ℃.

[0128] The above magnetron sputtering process forms a Ti / Al interface transition layer on the substrate surface with a thickness of about 2 μm. The interface transition layer is well bonded to the substrate, and the surface is uniform and without obvious defects.

[0129] 3) Plasma spraying deposition of anti-plasma ablation functional layer After completing the deposition of the interface transition layer, the anti-plasma ablation functional layer is deposited using the interface transition layer as the substrate.

[0130] Zirconia powder was selected as the anti-plasma ablation functional layer material, and multiple anti-ablation functional layers were deposited with powder particle size ranging from 10 to 45 μm.

[0131] The plasma spraying process parameters are set as follows: The plasma gas consists of argon and hydrogen, with an argon flow rate of 130 L / min. -1 The hydrogen flow rate is 12 L·min -1 ; The spraying current is 440 A, the spraying voltage is 90 V, and the spraying distance is 160 mm.

[0132] During the spraying process, the moving speed of the spray gun relative to the substrate is controlled at 5000 mm / s, and compressed air is used to continuously cool the back of the substrate, so that the surface temperature of the substrate is always controlled below 120 ℃, thereby reducing the instantaneous heat input during the spraying process.

[0133] Through multiple plasma spraying passes, a ZrO2 anti-plasma ablation functional layer with a thickness of about 250 μm is formed on the outside of the interface transition layer. The resulting composite film has a uniform surface without obvious defects and is tightly bonded to the substrate.

[0134] Performance testing The interfacial bonding strength between the composite film and the resin matrix was tested, and the test results showed that the bonding strength of the composite film was 44 MPa.

[0135] The samples were subjected to 500 plasma ablation tests. The test results showed that the mass ablation rate of the composite film was 4.32 mg / s, the surface integrity of the coating was good, and no large-area cracking or peeling was observed.

[0136] Example 7 In this embodiment, a CrN-Al2O3 composite film was prepared on a carbon fiber reinforced epoxy resin matrix (heat distortion temperature of about 350 °C).

[0137] 1) Matrix pretreatment The substrate surface was treated with laser etching, and the laser energy density was set to 0.8 J / mm². 2 The etching time was 3 min. Subsequently, the surface was ultrasonically cleaned with anhydrous ethanol for 110 s, and the substrate was dried after cleaning.

[0138] 2) Magnetron sputtering deposition interface transition layer In this embodiment, a Cr target is used for sputtering deposition: The process parameters for depositing the CrN layer were as follows: sputtering power of 0.9 kW, working pressure of 0.7 Pa, argon flow rate of 100 sccm, nitrogen flow rate of 35 sccm, and deposition time of 30 min.

[0139] The cooling system ensures that the substrate temperature does not exceed 100 °C. After deposition, a gradient transition layer with a thickness of 1.2 μm is obtained. The resulting interface transition layer is well bonded to the substrate and has a uniform surface without obvious defects.

[0140] 3) Plasma spraying deposition of anti-plasma ablation functional layer In this embodiment, alumina (Al2O3) is selected as the anti-plasma ablation functional layer material, and a single-layer anti-ablation functional layer is deposited with a powder particle size range of 10-45 μm.

[0141] The plasma spraying process parameters are set as follows: The plasma gas consists of argon and hydrogen, with an argon flow rate of 120 L / min. -1 The hydrogen flow rate is 10 L·min -1 ; The spraying current is 460 A, the spraying voltage is 100 V, and the spraying distance is 150 mm.

[0142] During the spraying process, the moving speed of the spray gun relative to the substrate is controlled to be no less than 5000 mm / s, and compressed air is used to continuously cool the back of the substrate, so that the surface temperature of the substrate is always controlled below 150 ℃, thereby reducing the instantaneous heat input during the spraying process.

[0143] Through multiple plasma spraying passes, an Al2O3 anti-plasma ablation functional layer with a thickness of about 300 μm is formed on the outside of the interface transition layer. The resulting composite film has a uniform surface without obvious defects and is tightly bonded to the substrate.

[0144] Performance testing The interfacial bonding strength between the composite film and the resin matrix was tested, and the test results showed that the bonding strength of the composite film was 40.5 MPa.

[0145] The samples were subjected to 500 plasma ablation tests. The test results showed that the mass ablation rate of the composite film was 4.26 mg / s, the coating surface was intact, and no large-area cracking or peeling was observed.

[0146] Comparative Example 1 This comparative example does not use magnetron sputtering to prepare the interface transition layer, but directly uses plasma spraying to prepare a TiO2 coating on a glass fiber reinforced epoxy resin matrix (heat distortion temperature of about 350 °C).

[0147] 1) Matrix pretreatment The substrate surface to be treated is cleaned and roughened. The sandblasting medium is 150-mesh white corundum sand. After sandblasting, the substrate surface is ultrasonically cleaned with anhydrous ethanol for 100 seconds to remove surface contaminants. After cleaning, the substrate is dried.

[0148] 2) Plasma spraying deposition of anti-plasma ablation functional layer In this comparative example, magnetron sputtering is not used to deposit the interface transition layer. Instead, glass fiber reinforced epoxy resin is used as the substrate to deposit the anti-plasma ablation functional layer.

[0149] In this embodiment, titanium dioxide ceramic powder is selected as the spraying material to deposit a single-layer ablation-resistant functional layer, and the powder particle size range is 10-45 μm.

[0150] Using the same plasma spraying process parameters as in Example 1: The plasma gas consists of argon and hydrogen, with an argon flow rate of 100 L·min. -1 The hydrogen flow rate is 10 L·min -1 ; The spraying current is 400 A, the spraying voltage is 100 V, and the spraying distance is 150 mm.

[0151] During the spraying process, the moving speed of the spray gun relative to the substrate is controlled to be no less than 4000 mm / s, and compressed air is used to continuously cool the back of the substrate.

[0152] A plasma ablation resistant functional layer with a thickness of approximately 100 μm was formed on the resin substrate surface through multi-pass plasma spraying. However, due to the significant thermophysical mismatch between the heat-sensitive resin substrate and the high-temperature ceramic droplets, the ceramic coating deposited directly on the resin substrate by plasma spraying exhibited low deposition efficiency, surface inhomogeneity, and noticeable microcracks and pores. Furthermore, because the high-energy heat input of the plasma jet exceeded the convective heat dissipation limit of the compressed air on the back side, thermal decomposition occurred on the substrate surface, leading to carbonization at the interface and severely affecting the interfacial bonding stability of the coating.

[0153] Performance testing The interfacial bonding strength between the composite film and the resin matrix was tested, and the test results showed that the bonding strength of the composite film was 5 MPa.

[0154] The samples were subjected to 500 plasma ablation tests. The test results showed that the mass ablation rate of the composite film was 10 mg / s, and obvious edge peeling and macro cracks appeared on the coating surface.

[0155] In Comparative Example 1, a single plasma spraying process was used to directly deposit an anti-plasma ablation functional layer on the resin substrate without introducing an interface transition layer. Due to the low heat distortion temperature of the resin substrate, the high-temperature plasma jet caused severe thermal damage to the substrate surface during direct plasma spraying, leading to thermal deformation and carbonization. This resulted in an uneven coating surface with microcracks and pores. After 500 plasma ablation tests, the coating's quality ablation rate was significantly higher than in other examples, and the coating surface exhibited obvious peeling and cracking, indicating that the coating prepared by this method has poor stability and durability under high-temperature conditions.

[0156] This invention provides a method for the synergistic preparation of ablation-resistant multi-scale composite films using magnetron sputtering and plasma spraying. By combining magnetron sputtering and plasma spraying, the protection of low-temperature resistant resin substrates under high-temperature plasma environments is solved. This method achieves effective synergy in interfacial bonding strength, high-temperature resistance, and plasma ablation resistance by depositing a dense interfacial transition layer on the resin substrate surface and then using plasma spraying to deposit an anti-plasma ablation functional layer. Through this method, a thick ceramic coating is obtained on the resin substrate surface, effectively solving the interfacial failure problem caused by high temperature and high heat flux density environments in traditional coating methods.

[0157] Figure 5 The image shows a comparison of the bonding strength between the ablation-resistant multi-scale composite film prepared in Examples 1-7 of this invention and the TiO2 coating prepared in Comparative Example 1. Figure 6 The changes in mass ablation rate of the ablation-resistant multi-scale composite films prepared in Examples 1-7 of this invention and the TiO2 coating prepared in Comparative Example 1 before and after ablation are shown. Figure 5 and Figure 6 As shown, the composite film not only has high interfacial bonding strength (not less than 40 MPa), but also exhibits excellent resistance to plasma ablation (mass ablation rate less than 5 mg / s), providing a feasible path for the long-term protective application of resin-based materials in high-temperature environments.

[0158] These embodiments demonstrate the feasibility of preparing high-bonding-strength, high-temperature-resistant, and plasma-ablation-resistant composite films on different resin matrix surfaces, proving that the method of the present invention can effectively improve the service performance of composite films under extreme thermal environments and meet the protection requirements under high-temperature plasma environments.

[0159] In summary, this invention provides an anti-ablation multi-scale composite film and a method for its synergistic preparation and application using magnetron sputtering and plasma spraying. This method combines magnetron sputtering and plasma spraying processes. First, magnetron sputtering is used to deposit a micron-sized dense interfacial transition layer on the resin substrate surface at low temperature. Then, plasma spraying is used to efficiently deposit a sub-millimeter-sized anti-plasma ablation functional layer on the transition layer, forming a multi-scale composite film with high bonding strength, excellent high-temperature resistance, and anti-plasma ablation properties. During this preparation process, by controlling the low-temperature conditions during magnetron sputtering and the heat input during plasma spraying, thermal damage to the resin substrate is effectively avoided, improving the bonding strength and stability of the film. This method offers high process flexibility, applicable to high-temperature surface protection of different resin substrate materials, and allows adjustment of the structure and thickness of the functional layer to meet specific high-temperature resistance and ablation resistance requirements. After 500 plasma ablation tests, the composite film exhibited a low mass ablation rate (less than 5 mg / s) and high interfacial bonding strength (not less than 40 MPa), demonstrating its excellent performance and long-term reliability under high-temperature conditions.

[0160] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for synergistically preparing an ablation-resistant cross-scale composite film layer by magnetron sputtering-plasma spraying, characterized in that, include: Pretreatment of the resin matrix; Under conditions below the heat distortion temperature of the resin matrix, a continuous and dense metal-based thin film is deposited on the surface of the pretreated resin matrix by magnetron sputtering to form an interface transition layer. Using the interface transition layer as a substrate, an anti-plasma ablation functional layer is deposited by plasma spraying, with the temperature of the resin matrix not exceeding 150 °C during the spraying process, to obtain an anti-ablation multi-scale composite film layer formed on the surface of the resin matrix.

2. The method for preparing ablation-resistant multi-scale composite films by magnetron sputtering-plasma spraying according to claim 1, characterized in that, The pretreatment includes roughening the surface of the resin matrix by sandblasting, laser etching and chemical roughening, followed by ultrasonic cleaning of the resin matrix surface with anhydrous ethanol for 90-120 s; the resin matrix is ​​a resin or resin-based composite material with a heat distortion temperature not higher than 350 ℃.

3. The method for preparing ablation-resistant multi-scale composite films by magnetron sputtering-plasma spraying according to claim 1, characterized in that, The material of the interface transition layer is at least one of Ti, Cr, Al, TiO2 and CrN, and the thickness of the interface transition layer is 1-4 μm.

4. The method for preparing ablation-resistant multi-scale composite films by magnetron sputtering-plasma spraying according to claim 1, characterized in that, The process parameters for magnetron sputtering include: sputtering power of 0.5-2.0 kW, working pressure of 0.3-0.8 Pa, argon flow rate of 60-150 sccm, and deposition time of 60-150 min; the temperature of the resin matrix during deposition shall not exceed 120 ℃.

5. The method for preparing ablation-resistant multi-scale composite films by magnetron sputtering-plasma spraying synergistically according to claim 1, characterized in that, The anti-plasma ablation functional layer is made of at least one of titanium oxide, aluminum oxide, zirconium oxide, yttrium-stabilized zirconium oxide, and silicon carbide, with a particle size of 10-45 μm; the thickness of the anti-plasma ablation functional layer is 200-500 μm.

6. The method for preparing ablation-resistant multi-scale composite films by magnetron sputtering-plasma spraying according to claim 1, characterized in that, The anti-plasma ablation functional layer can be a single-layer structure, a multi-layer structure, or a gradient structure.

7. The method for preparing ablation-resistant multi-scale composite films by magnetron sputtering-plasma spraying according to claim 1, characterized in that, The process parameters for plasma spraying include: argon flow rate of 60-150 L·min. -1 The hydrogen flow rate is 10-15 L·min -1 The current is 400-500 A, the voltage is 80-100 V, the spraying distance is 100-180 mm, and the moving speed of the spray gun relative to the substrate is not less than 4000 mm / s. During the spraying process, compressed air is used to cool the back of the substrate so that the substrate temperature does not exceed 150 ℃.

8. An ablative, cross-scale composite film layer, characterized in that, The ablation-resistant multi-scale composite film was prepared by the method described in any one of claims 1-7, which involves magnetron sputtering and plasma spraying.

9. The ablative cross-scale composite film layer of claim 8, wherein, The anti-ablation multi-scale composite film includes an interface transition layer disposed on the surface of the resin matrix; and an anti-plasma ablation functional layer disposed outside the interface transition layer; the total bonding strength between the anti-ablation multi-scale composite film and the resin matrix is ​​not less than 40 MPa, and the mass ablation rate is less than 5 mg / s after undergoing 500 plasma ablation tests.

10. The application of the ablation-resistant multi-scale composite film layer according to any one of claims 8 or 9 in the preparation of aircraft structural components, thermal insulation components and functional load-bearing components.

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