A high-entropy alloy composite film, its preparation method and application

Abstract

This invention belongs to the field of surface protection technology, specifically relating to a high-entropy alloy composite film, its preparation method, and its application. The preparation method of the high-entropy alloy composite film provided by this invention employs alternating magnetron sputtering and ion beam deposition of the high-entropy alloy film, thereby enhancing the adhesion between the film and the substrate, maintaining good surface roughness, and significantly improving the wear resistance of the film surface. Subsequent ion doping of the high-entropy alloy film increases the film density, reduces the number of microcells on the surface and the number of channels for corrosive media to reach the substrate, and also reduces the number of channels for oxidizing media to reach the substrate, thereby improving the film quality, corrosion resistance, and high-temperature resistance. Simultaneously, it further increases the film's hardness and reduces its coefficient of friction, thus enabling the preparation of a wear-resistant, corrosion-resistant, and high-temperature-resistant high-entropy alloy-like two-dimensional layered film on the substrate surface.

Description

Technical Field

[0001] This invention belongs to the field of surface protection technology, specifically relating to a high-entropy alloy composite film, its preparation method, and its application. Background Technology

[0002] Aerospace equipment typically requires high temperature resistance, wear resistance, and corrosion resistance. Ordinary coatings can no longer solve these problems. High-entropy alloy coatings, due to their excellent strength, toughness, corrosion resistance, and wear resistance, have seen rapid development in the field of surface engineering and are expected to become an ideal means of surface strengthening for key components of equipment designed for extreme environments such as wear resistance, corrosion resistance, and heat resistance.

[0003] Among existing high-entropy alloy thin film preparation technologies, magnetron sputtering, thermal spraying, and laser cladding are widely used. Magnetron sputtering offers fast deposition rates, dense film structures, and excellent mechanical properties, and allows for flexible control of film thickness and properties through process parameters. However, numerous studies have shown that high-entropy alloy thin films prepared by magnetron sputtering have limited thickness. Due to significant differences in bonding types between the substrate and the film, and limitations in the preparation process, it is difficult for the film to form good chemical bonds with the substrate, resulting in poor adhesion. Atmospheric plasma spraying (APS) technology in thermal spraying offers advantages such as high flame temperature, concentrated energy, high adhesion strength, high deposition efficiency, and low coating dilution rate. However, because it is difficult to maintain a high bonding rate at the interface between particle layers in high-entropy alloy coatings prepared by thermal spraying, some defects and inclusions still exist in the coating. Furthermore, the spraying process is carried out in an atmospheric environment, where molten particles easily react with the gas to form oxide inclusions. Laser cladding technology has the advantages of high energy density and rapid cooling of the cladding layer, which can effectively avoid the segregation of coating components and the high bonding strength between the coating and the substrate. However, large stress is easily generated during the powder mixing process, and the coating is prone to defects such as pores and cracks, which can easily lead to breakage.

[0004] Therefore, how to overcome the above-mentioned defects in existing high-entropy alloy thin film preparation technology, so as to obtain high-entropy alloy thin films with high film quality (no pores, no cracks, no inclusions) and good wear resistance, corrosion resistance and high temperature resistance, is a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0005] In view of this, the technical problem to be solved by the present invention is the defects of high-entropy alloy thin films prepared by existing methods, such as low film quality, poor film-substrate bonding, poor wear and corrosion resistance, and limited controllability of film elements. Therefore, the present invention provides a high-entropy alloy composite film with high film quality, wear resistance, corrosion resistance, and high temperature resistance, as well as its preparation method and application.

[0006] The objective of this invention is achieved through the following technical solution:

[0007] In a first aspect, according to embodiments of the present invention, the present invention provides a high-entropy alloy composite film, comprising a high-entropy alloy film body and an ion-doped layer extending from the surface of the high-entropy alloy film body into its interior.

[0008] In an embodiment of the present invention, the thickness of the ion-doped layer is 1‰ to 20% of the thickness of the high-entropy alloy film body.

[0009] In an embodiment of the present invention, the mass percentage of ions doped in the ion-doped layer is 1% to 10%.

[0010] In embodiments of the present invention, the material of the high-entropy alloy film body is any one of CoCrFeNiMn, AlCoCrFeNi, CuCoCrFeNi, CoCrFeNiTi, and TaNbHfZr.

[0011] In an embodiment of the present invention, the ions doped in the ion-doped layer are Ti. 2+ Mo 2+ Al 3+ Cr 3+ Cu 2+ At least one of them.

[0012] Secondly, according to embodiments of the present invention, the present invention also provides a method for preparing a high-entropy alloy composite film, comprising the following steps:

[0013] S1. Vacuum ion cleaning of the substrate surface;

[0014] S2. The high-entropy alloy target is bombarded sequentially with a magnetron sputtering source and an ion source, alternating 5 to 6 times, ending with ion source bombardment. A film is deposited on the substrate surface after step S1 to form a high-entropy alloy film body.

[0015] S3. The surface of the high-entropy alloy film body is ion-doped with metal ions to obtain the final product.

[0016] In an embodiment of the present invention, in step S2, the magnetron sputtering target diameter is 50–150 mm, the sputtering voltage is 400–800 V, the sputtering current is 1–5 A, the flow rate ratio of Ar gas and N2 gas is 0.2–0.5:1, and the sputtering pressure is 0.5 × 10⁻⁶. -1 ~2.0×10 -1 Pa, pulse negative bias voltage is -30 to -600V, and the time for each sputtering is 5 to 30 minutes.

[0017] In an embodiment of the present invention, in step S2, the ion source uses 99.99% var. Ar gas, and its operating pressure is 1.0 × 10⁻⁶. -2 ~3.0×10-2 Pa, with each ion bombardment lasting 5–20 minutes.

[0018] In embodiments of the present invention, the material of the high-entropy alloy film body is any one of CoCrFeNiMn, AlCoCrFeNi, CuCoCrFeNi, CoCrFeNiTi, and TaNbHfZr.

[0019] In an embodiment of the present invention, in step S3, the energy voltage for ion doping is 10–100 keV, and the doping dose is 1.0 × 10⁻⁶. 17 ~4.0×10 17 ions / cm 2 .

[0020] In an embodiment of the present invention, the metal ion is Ti. 2+ Mo 2+ Al 3+ Cr 3+ Cu 2+ At least one of them.

[0021] In an embodiment of the present invention, in step S1, the surface of the substrate is bombarded with low-energy ions. The ion source gas is 99.99% Ar gas with a working pressure of 0.1 Pa to 5 Pa and a negative bias voltage of -400 to -1000 V. The surface of the substrate is cleaned by glow discharge, and the bombardment time is 20 to 30 minutes.

[0022] In an embodiment of the present invention, steps S1 to S3 are performed at a vacuum degree of 3.0 × 10⁻⁶. -4 ~1.8×10 -3 It was carried out under the condition of Pa.

[0023] In an embodiment of the present invention, a pretreatment step is included before step S1: first, the surface of the substrate is wiped with a degreasing solvent, then the substrate is immersed in tetrachloroethylene for 10 to 30 minutes, then ultrasonically cleaned in a metal cleaning agent for 10 to 20 minutes, and then dried.

[0024] In an embodiment of the present invention, a packaging step is included after step S3: the substrate on which the high-entropy alloy composite film is prepared is placed in an ethanol aqueous solution for ultrasonic cleaning for 5 to 10 minutes, dried, and then vacuum sealed for storage.

[0025] Thirdly, according to embodiments of the present invention, the above-described high-entropy alloy composite film or the high-entropy alloy composite film prepared by the above-described preparation method is used in bearings, gears, blades, and splined shafts.

[0026] Compared with the prior art, the technical solution of the present invention has the following advantages:

[0027] 1. The method for preparing a high-entropy alloy composite film provided in this invention employs alternating magnetron sputtering and ion beam deposition of the high-entropy alloy film. This enhances the adhesion between the film and the substrate, maintains good surface roughness, and significantly improves the wear resistance of the film surface. Subsequently, the high-entropy alloy film is ion-doped. High-energy ions injected into the surface of the high-entropy alloy film collide with the atoms on the film surface, damaging the original crystal structure and forming an amorphous, grain-boundary-free surface layer. Since the amorphous phase lacks defects such as grain boundary dislocations, it increases the film density, reduces the number of microcells on the surface and the number of channels for corrosive media to reach the substrate, and also reduces the number of channels for oxidizing media to reach the substrate. This improves the film quality, corrosion resistance, and high-temperature resistance. Furthermore, it can further increase the film's hardness and reduce its coefficient of friction, thus preparing a wear-resistant, corrosion-resistant, and high-temperature-resistant high-entropy alloy-like two-dimensional layered film on the substrate surface. Moreover, the preparation method of this invention, through ion doping, can further control the elements of the film layer, allowing for the adjustment of the film's material composition according to the desired film properties.

[0028] 2. The method for preparing high-entropy alloy composite films provided in this embodiment of the invention can better control the growth of thin films by adjusting parameters such as sputtering voltage, sputtering current, ion doping energy, doping elements, and ion doping dosage. The film structure can be optimized by alternating deposition of composite ion doping, and finally a high-entropy alloy functional composite film with wear resistance, corrosion resistance, and high temperature resistance can be formed.

[0029] 3. The high-entropy alloy composite film provided in this embodiment of the invention includes a high-entropy alloy film body and an ion-doped layer extending from the surface of the high-entropy alloy film body into its interior. By incorporating metal ions to a certain depth into the interior of the high-entropy alloy film body, a structural layer with an integrated amorphous-nanocrystalline-fine-crystalline structure is formed, which greatly improves the wear resistance, corrosion resistance and high temperature resistance of the film. This allows the high-entropy alloy composite film of the present invention to be applied in military fields such as mechanical gears, bearings, and spline transmissions under extreme conditions such as high temperature.

[0030] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0031] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0032] Figure 1 The flowchart illustrates the preparation process of the high-entropy alloy composite film provided by this invention.

[0033] Figure 2 This is a cross-sectional view of the high-entropy alloy composite film prepared in Example 1.

[0034] Figure 3 This is a schematic diagram of the structure of the high-entropy alloy composite film prepared in Example 1.

[0035] Figure 4 The figures show the friction and wear curves of the high-entropy alloy films prepared in Example 1 and Comparative Example 1.

[0036] Figure 5 The graphs show the polarization curves of the high-entropy alloy films prepared in Example 1 and Comparative Example 1.

[0037] Figure 6 The image shows the surface morphology of the high-entropy alloy composite film prepared in Example 1.

[0038] Figure 7 The image shows the surface morphology of the high-entropy alloy film prepared in Comparative Example 1.

[0039] Figure 8 The image shows the nanohardness of the high-entropy alloy films prepared in Example 1 and Comparative Example 1.

[0040] Figure 9 This is a 2D cross-sectional profile of the wear track after friction and wear of the high-entropy alloy composite film prepared in Example 1.

[0041] Figure 10 The image shows the 2D cross-sectional profile of the wear track after friction and wear of the high-entropy alloy film prepared in Comparative Example 1. Detailed Implementation

[0042] The following embodiments are provided to better understand the present invention and are not limited to the preferred embodiments described. They do not constitute a limitation on the content and scope of protection of the present invention. Any product that is the same as or similar to the present invention, derived by any person under the guidance of the present invention or by combining the features of the present invention with other prior art, falls within the protection scope of the present invention.

[0043] For experiments not specifically described in the examples, the procedures or conditions should be followed according to the conventional experimental procedures described in the literature in this field. Reagents or instruments whose manufacturers are not specified are all commercially available conventional reagent products.

[0044] This invention is based on the following discoveries of the inventors:

[0045] Among existing high-entropy alloy thin film preparation technologies, magnetron sputtering offers fast deposition rates, dense film structures, and excellent mechanical properties. Furthermore, the thickness and properties of the film can be flexibly controlled through process parameters. However, numerous studies have shown that the thickness of high-entropy alloy films prepared by magnetron sputtering is limited. Due to significant differences in bonding types between the substrate and the film, and limitations imposed by the preparation process, it is difficult for the film to form good chemical bonds with the substrate, resulting in poor adhesion. Atmospheric plasma spraying (APS) technology in thermal spraying offers advantages such as high flame temperature, concentrated energy, high bonding strength, high deposition efficiency, and low coating dilution rate. However, the high-entropy alloy coating prepared by thermal spraying struggles to maintain a high bonding rate at the interface between particle layers, leading to some defects and inclusions in the coating. Additionally, the spraying process is conducted in an atmospheric environment, where molten particles easily react with the gas to generate oxide inclusions. Laser cladding technology offers advantages such as high energy density and rapid cooling of the cladding layer, effectively avoiding coating component segregation and providing high bonding strength between the coating and the substrate. However, significant stress is easily generated during powder mixing, making the coating prone to defects such as pores and cracks, and increasing the risk of breakage.

[0046] Therefore, this invention proposes a high-entropy alloy composite film with high film quality (no pores, cracks, or inclusions) and excellent wear resistance, corrosion resistance, and high-temperature resistance, as well as its preparation method. The preparation method employs alternating magnetron sputtering and ion beam deposition of the high-entropy alloy film, which enhances the adhesion between the film and the substrate, maintains good surface roughness, and significantly improves the wear resistance of the film surface. Subsequently, the high-entropy alloy film is ion-doped. The high-energy ions collide with the atoms on the film surface, damaging the original crystal lattice structure and forming an amorphous, grain boundary-free surface layer. In this amorphous phase, there are no defects such as grain boundary dislocations, thus increasing the film density, reducing the number of microcells on the surface and the number of channels for corrosive media to reach the substrate, thereby improving the corrosion resistance and film quality. Ion doping can further enhance the wear resistance of thin films. There are two mechanisms for this effect: First, it can improve the toughness of the film surface through the precipitation of hardened phases. When active ions are introduced into the film, fine and dispersed hard phases of carbides and nitrides can be formed. As the number of doped ions increases, these hardened phases continue to aggregate, thereby increasing the surface hardness of the material. Second, it can reduce the coefficient of friction. After high-energy ions collide with lattice atoms, a large number of atoms leave their original lattice positions, resulting in high distortion and the formation of an amorphous structure, thus reducing the coefficient of friction of the film surface. In summary, the preparation method of this invention uses magnetron sputtering and ion beam deposition processes to prepare a thin film on the substrate surface, and then performs anti-wear and anti-corrosion ion doping on the thin film surface, thereby preparing a wear-resistant and corrosion-resistant high-entropy alloy composite film on the substrate surface. This can improve the film-substrate adhesion, significantly reduce the surface friction coefficient of the workpiece, and enhance wear and corrosion resistance. It can be used in mechanical parts such as pump valve bearings and gears that require wear and corrosion resistance, such as high-temperature bearings in aerospace, meeting the wear and corrosion resistance requirements in the range of 300-1000℃. This method solves the problems of poor film-substrate adhesion and the tendency for defects such as pores and cracks in the film caused by the preparation of near-two-dimensional high-entropy alloy thin films in the prior art, thus improving wear and corrosion resistance.

[0047] The following is for reference. Figure 1 The preparation method of the wear-resistant, corrosion-resistant, and high-temperature-resistant high-entropy alloy composite film provided in the embodiments of the present invention will be described in detail. According to the embodiments of the present invention, the method includes the following steps:

[0048] S0. Pre-treat the surface of the substrate to remove oil, rust, and impurities adhering to the surface of the metal substrate.

[0049] In this step, a metal degreasing solvent is used to remove surface oil stains from the metal material, and tetrachloroethylene reagent is used to soak the metal material for 10-20 minutes to remove residual grease and impurities from the surface. The metal material is then ultrasonically cleaned in an ultrasonic cleaner for 10-20 minutes with a metal cleaning agent to remove organic residues from the surface. Finally, the metal material is placed in a drying oven to dry for 10-20 minutes.

[0050] Specifically, firstly, use a metal degreasing solvent to wipe away oil stains from the metal substrate material, ensuring its surface is free of oil. Then, immerse the substrate material in clean tetrachloroethylene for 10-20 minutes, remove it, absorb any remaining solvent with Xuan paper, and finally wipe it with clean silk. Next, place the treated substrate material in a metal cleaning agent and ultrasonically clean it for 10-20 minutes. Remove it and wipe it dry with a clean silk cloth, wiping the smooth surface of the material in the same direction to ensure no water stains or impurities remain. Do not use contaminated or wet silk cloths to wipe the specimen. Finally, place it in a drying oven to dry for 10-20 minutes. It should be noted that those skilled in the art can select the specific type of metal degreasing solvent and metal cleaning agent according to actual needs. For example, the metal degreasing solvent can be a commercially available common metal degreasing solvent, whose components include sodium silicate, sodium carbonate, sodium hydroxide, solvent water, etc.; the tetrachloroethylene used for cleaning is a commercially available common organic solvent, or other organic solvents can be used instead; the metal cleaning agent can be an environmentally friendly metal cleaning agent composed of a mixture of nonionic surfactant, organic alkali and pure water.

[0051] S1. Place the pretreated substrate into the vacuum chamber of the coating device, evacuate the vacuum chamber, and then use an ion source to bombard the surface of the substrate with low-energy ions for vacuum ion cleaning.

[0052] In this step, the vacuum level is 3.0 × 10⁻⁶. -4 Pa ~ 1.8 × 10 -3 Under the condition of Pa, vacuum ion cleaning is performed by bombarding the substrate surface with low-energy ions using an ion source. The ion source gas is Ar gas with a purity of 99.99%. Ar gas is introduced into the vacuum chamber to make its working gas pressure 0.1Pa~5Pa. The negative bias voltage of the low-energy ion bombardment is -400V~-1000V to perform glow discharge power generation and clean the substrate surface.

[0053] Specifically, vacuum ion cleaning is performed by bombarding the substrate surface with low-energy ions, and the substrate surface is heated. The bombardment time is 20-30 minutes. It should be noted that those skilled in the art can select the specific negative bias conditions according to actual needs. According to a specific embodiment of the present invention, the ion cleaning effect is good when the negative bias voltage of the low-energy ion bombardment is -500V.

[0054] S2. Select a high-entropy alloy target and use an ion beam-assisted deposition device to deposit a film on the substrate surface.

[0055] In this step, a high-entropy alloy film composite deposition modification is performed on the substrate surface by alternating between magnetron sputtering and ion beam deposition. CoCrFeNiMn (purity of 99.99%) target material is used. First, the magnetron sputtering source is turned on, and the deposition time is 5 min to 30 min. Then, the ion source is turned on, and the ion bombardment time is 5 min to 20 min. This alternation is repeated 5 to 10 times until the ion bombardment ends.

[0056] Specifically, the magnetron sputtering source has a sputtering voltage of 400V to 800V, a sputtering current of 1A to 5A, and is supplied with Ar and N2 gases, with the flow rate ratio controlled at Ar / N2 = 0.2 to 0.5:1. The sputtering gas pressure is 0.5 × 10⁻⁶. -1 Pa ~ 2.0 × 10 -1 Pa, with a pulsed negative bias voltage of -30V to -600V. The magnetron sputtering target diameter is 50-150mm. It should be noted that the number of alternating deposition cycles when using a magnetron sputtering source and ion beam deposition to modify the substrate surface is not limited; those skilled in the art can select the specific negative bias conditions according to actual needs. According to a specific embodiment of the present invention, six alternating deposition cycles are performed. The inventors have found that this number of alternating deposition cycles can significantly yield a novel high-entropy alloy film with superior performance.

[0057] S3. Metal ions are used to dope the surface of the high-entropy alloy film to prepare a wear-resistant and corrosion-resistant high-entropy alloy composite film on the substrate surface.

[0058] In this step, a high-energy ion beam is used to dope metal ions onto the surface of the high-entropy alloy film obtained in step S2. The metal ions can be chromium, titanium, molybdenum, aluminum, copper, etc. Doping with metal ions can lead to grain refinement within the doping depth range, forming substitutional and interstitial solid solutions, significantly improving wear resistance and corrosion resistance. Specifically, a metal target with a purity of 99.98% can be used for metal ion doping, with a doping energy of 10 keV to 100 keV and a doping dose of 1.0 × 10⁻⁶. 17 ions / cm 2 ~4.0×10 17 ions / cm 2 .

[0059] S4. Finally, the metal material with the wear-resistant and corrosion-resistant high-entropy alloy composite film is cleaned, dried, and vacuum-sealed.

[0060] In this step, the material is cleaned, dried, and vacuum-sealed. The metal material with a wear-resistant and corrosion-resistant high-entropy alloy composite film on its surface is placed in an alcohol solution and ultrasonically cleaned for 5-10 minutes using an ultrasonic cleaner. After cleaning, it is removed, wiped dry with a clean cloth, and then placed in a drying oven to dry for 10-20 minutes. The dried metal material is then vacuum-sealed using a vacuum sealing machine.

[0061] The present invention will now be described with reference to specific embodiments. It should be noted that these embodiments are merely descriptive and do not limit the present invention in any way.

[0062] Example 1

[0063] This embodiment provides a method for preparing a high-entropy alloy composite film, including the following steps:

[0064] S0. Use a commercially available metal degreasing solvent to remove oil stains from the surface of the bearing (metal substrate material) of the pump valve, ensuring that the surface is free of grease. Then, immerse the substrate material in clean tetrachloroethylene for 15 minutes, remove it, absorb any residual solvent with Xuan paper, and finally wipe it with clean silk. Next, immerse the treated substrate material in a commercially available metal cleaning agent and ultrasonically clean it for 15 minutes. Remove it and wipe it dry with a clean silk cloth. When drying, wipe the smooth surface of the material in the same direction to ensure that there are no water stains or impurities remaining on the surface. Do not use contaminated or wet silk cloths to wipe the test piece. Then, place it in a drying oven to dry for 10 minutes.

[0065] S1. Place the pretreated metal substrate material onto the tooling table of the vacuum chamber of the coating apparatus, and evacuate the vacuum chamber to a vacuum level of 3.0 × 10⁻⁶. -4 Under the condition of Pa, vacuum ion cleaning is performed by bombarding the substrate surface with low-energy ions using an ion source. The gas source is Ar gas with a purity of 99.99%. Ar gas is introduced into the vacuum chamber to make its working gas pressure 1.8 Pa. The negative bias voltage of the low-energy ion bombardment of the ion source is -500 V, and glow discharge power generation is performed to clean the substrate surface.

[0066] S2. Using a magnetron sputtering source and an ion beam, the CoCrFeNiMn target is alternately bombarded to deposit a thin film on the substrate surface after step S1. First, the magnetron sputtering source is turned on. The magnetron sputtering target diameter is 100 mm, the operating voltage of the magnetron sputtering source is 500 V, the sputtering current is 1 A, and Ar and N2 gases are introduced, with the flow rate ratio controlled at Ar / N2 = 0.3. The sputtering gas pressure is 1.0 × 10⁻⁶. - 1 Pa, pulsed negative bias voltage of -90V, deposition time of 15min, magnetron sputtering source turned off, then ion source turned on for ion beam deposition, Ar gas was introduced into the vacuum chamber to achieve a working pressure of 2.0×10 Pa.-2 A high-entropy alloy thin film was prepared on the substrate surface by applying a pressure of Pa, a voltage of 10 kV, an ion beam deposition time of 15 min, alternating 6 times, ending with ion bombardment.

[0067] S3. Using a Ti target with a purity of 99.98 wt.%, Ti ions are doped onto the surface of the high-entropy alloy film prepared in step S2 using a metal ion source. The ion doping energy is 80 keV, and the doping dose is 3.0 × 10⁻⁶. 17 ions / cm 2 The high-entropy alloy composite film was prepared on the substrate surface by incorporating it in two stages, each time adding half of the total dosage.

[0068] S4. Place the metal material with the prepared film into an alcohol aqueous solution, ultrasonically clean it for 10 minutes using an ultrasonic cleaner, remove it and wipe it dry with a clean silk cloth, then place it in a drying oven to dry for 10 minutes, and vacuum seal the dried metal material using a vacuum sealing machine.

[0069] like Figure 2 and Figure 3 As shown, the high-entropy alloy composite film prepared in this embodiment includes a high-entropy alloy film body 10 (disposed on the surface of the substrate 01) and an ion-doped layer 11 extending from the surface of the high-entropy alloy film body 10 into its interior. In this embodiment, the thickness of the ion-doped layer 11 is 52 nm, accounting for 10% of the total thickness of the high-entropy alloy film body 10, and the mass percentage of ions doped in the ion-doped layer is 2%. See also Figure 3 Furthermore, the ion-doped layer 11 includes an amorphous layer 111 and a nanocrystalline layer 112. The amorphous layer 111 is located on the surface of the high-entropy alloy film body 10 and outside the nanocrystalline layer 112. Inside the nanocrystalline layer 112 is a fine-grained layer 113. This integrated amorphous-nanocrystalline-fine-grained structure layer is beneficial to significantly improve the wear resistance and corrosion resistance of the film.

[0070] Example 2

[0071] Except for the following, the rest of the content is the same as in Example 1.

[0072] Step S2: Thin film deposition is performed on the substrate surface obtained in Step S1 by alternately bombarding the CoCrFeNiMn target with a magnetron sputtering source and an ion beam. First, the magnetron sputtering source is turned on. The magnetron sputtering target diameter is 50 mm, the operating voltage of the magnetron sputtering source is 800 V, the sputtering current is 5 A, and Ar and N2 gases are introduced, with the flow rate ratio controlled at Ar / N2 = 0.2. The sputtering gas pressure is 2.0 × 10⁻⁶. - 1Pa, pulsed negative bias voltage of -300V, deposition time of 20min, magnetron sputtering source turned off, then ion source turned on for ion beam deposition, Ar gas was introduced into the vacuum chamber to make its working pressure 1.0×10 -2 A high-entropy alloy thin film was prepared on the substrate surface by applying a pressure of Pa, a voltage of 10 kV, an ion beam deposition time of 10 min, alternating 6 times, ending with ion bombardment.

[0073] Example 3

[0074] Except for the following, the rest of the content is the same as in Example 1.

[0075] Step S2: Thin film deposition is performed on the substrate surface obtained in Step S1 by alternately bombarding the CoCrFeNiMn target with a magnetron sputtering source and an ion beam. First, the magnetron sputtering source is turned on. The magnetron sputtering target diameter is 150 mm, the operating voltage of the magnetron sputtering source is 600 V, the sputtering current is 1 A, and Ar and N2 gases are introduced, with the flow rate ratio controlled at Ar / N2 = 0.5. The sputtering gas pressure is 0.5 × 10⁻⁶. -1 Pa, pulsed negative bias voltage of -600V, deposition time of 10min, magnetron sputtering source turned off, then ion source turned on for ion beam deposition, Ar gas was introduced into the vacuum chamber to make its working pressure 0.5×10 -2 A high-entropy alloy thin film was prepared on the substrate surface by applying a pressure of Pa, a voltage of 10 kV, an ion beam deposition time of 20 min, alternating 5 times, ending with ion bombardment.

[0076] Example 4

[0077] Except for the following, the rest of the content is the same as in Example 1.

[0078] Step S3: Using a Ti target with a purity of 99.98 wt.%, Ti ions are doped onto the surface of the high-entropy alloy film prepared in step S2 using a metal ion source. The ion doping energy is 55 keV, and the doping dose is 4.0 × 10⁻⁶. 17 ions / cm 2 Finally, a high-entropy alloy composite film was prepared on the surface of the substrate.

[0079] Example 5

[0080] Except for the following, the rest of the content is the same as in Example 1.

[0081] Step S3: Using a 99.99 wt.% pure Cr target, Cr ions are doped onto the surface of the high-entropy alloy film prepared in step S2 using a metal ion source. The ion doping energy is 10 keV, and the doping dose is 2.5 × 10⁻⁶. 17 ions / cm 2Finally, a high-entropy alloy composite film was prepared on the surface of the substrate.

[0082] Example 6

[0083] Except for the following, the rest of the content is the same as in Example 1.

[0084] Step S2: Use AlCoCrFeNi pentagonal metal target.

[0085] Step S3: Using a Mo target with a purity of 99.99 wt.%, Mo ions are doped onto the surface of the high-entropy alloy film prepared in step S2 using a metal ion source. The ion doping energy is 100 keV, and the doping dose is 2.0 × 10⁻⁶. 17 ions / cm 2 Finally, a high-entropy alloy composite film was prepared on the surface of the substrate.

[0086] Comparative Example 1

[0087] Except for the following, the rest of the content is the same as in Example 1.

[0088] Step S3 is omitted in this comparative example.

[0089] Figure 4 The figures shown are the tribological wear curves of the high-entropy alloy films prepared in Example 1 and Comparative Example 1. Figure 4 It can be seen that after ion doping (Example 1), the friction coefficient of the high-entropy alloy coating is significantly reduced, by about 57%.

[0090] Figure 5 The figure shows the polarization curves of the high-entropy alloy films prepared in Example 1 and Comparative Example 1. Figure 5 As can be seen, after ion doping (Example 1), the corrosion resistance of the high-entropy alloy coating is greatly improved, and the corrosion current is reduced by 1 time.

[0091] Figure 6 and Figure 7 These are surface morphology images of the high-entropy alloy films prepared in Example 1 and Comparative Example 1, respectively. Figure 6-7 It can be seen that ion doping (Example 1) can significantly improve the density and surface finish of high-entropy alloy coatings.

[0092] Figure 8 The nanohardness maps of the high-entropy alloy films prepared in Example 1 and Comparative Example 1 are shown below. Figure 8 It can be seen that after ion doping (Example 1), the hardness of the high-entropy alloy coating increased by 7%.

[0093] Figure 9 and Figure 10 The images show the 2D cross-sectional profiles of the wear tracks after friction and wear on the high-entropy alloy films prepared in Example 1 and Comparative Example 1. Figure 9-10 As can be seen, after ion doping (Example 1), the wear mark depth was reduced by about 70%, which significantly improved the wear resistance of the high-entropy alloy coating.

[0094] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A high-entropy alloy composite film, characterized in that, It includes a high-entropy alloy film body and an ion-doped layer extending from the surface of the high-entropy alloy film body into its interior; The method for preparing the high-entropy alloy composite film includes the following steps: S1. Vacuum ion cleaning of the substrate surface; S2. The high-entropy alloy target is bombarded sequentially with a magnetron sputtering source and an ion source, alternating 5 to 6 times, ending with ion source bombardment. A film is deposited on the substrate surface after step S1 to form a high-entropy alloy film body. S3. The surface of the high-entropy alloy film body is ion-doped with metal ions; The ions doped in the ion-doped layer are Ti. 2+ Mo 2+ Al 3+ Cr 3+ Cu 2+ At least one of them.

2. The high-entropy alloy composite film according to claim 1, characterized in that, The thickness of the ion-doped layer is 1‰ to 20% of the thickness of the high-entropy alloy film body; and / or, The mass percentage of ions doped in the ion-doped layer is 1% to 10%.

3. The high-entropy alloy composite film according to claim 1, characterized in that, The material of the high-entropy alloy film body is any one of CoCrFeNiMn, AlCoCrFeNi, CuCoCrFeNi, CoCrFeNiTi, and TaNbHfZr.

4. A method for preparing a high-entropy alloy composite film according to any one of claims 1-3, characterized in that, Includes the following steps: S1. Vacuum ion cleaning of the substrate surface; S2. The high-entropy alloy target is bombarded sequentially with a magnetron sputtering source and an ion source, alternating 5 to 6 times, ending with ion source bombardment. A film is deposited on the substrate surface after step S1 to form a high-entropy alloy film body. S3. The surface of the high-entropy alloy film body is ion-doped with metal ions; The metal ion is Ti. 2+ Mo 2+ Al 3+ Cr 3+ Cu 2+ At least one of them.

5. The method for preparing the high-entropy alloy composite film according to claim 4, characterized in that, In step S2, the magnetron sputtering target diameter is 50~150mm, the sputtering voltage is 400~800V, the sputtering current is 1~5A, the flow rate ratio of Ar gas and N2 gas is 0.2~0.5:1, and the sputtering pressure is 0.5×10⁻⁶. -1 ~2.0×10 -1 Pa, pulse negative bias voltage is -30~-600V, and the time for each sputtering is 5~30min.

6. The method for preparing the high-entropy alloy composite film according to claim 4, characterized in that, In step S2, the ion source uses 99.99% var. Ar gas, and its working pressure is 1.0 × 10⁻⁶. -2 ~3.0×10 -2 Pa, with each ion bombardment lasting 5–20 min; and / or, The material of the high-entropy alloy film body is any one of CoCrFeNiMn, AlCoCrFeNi, CuCoCrFeNi, CoCrFeNiTi, and TaNbHfZr.

7. The method for preparing the high-entropy alloy composite film according to any one of claims 4 to 6, characterized in that, In step S3, the energy voltage for ion doping is 10~100 keV, and the dopant dosage is 1.0×10⁻⁶. 17 ~4.0×10 17 ions / cm 2 .

8. The method for preparing the high-entropy alloy composite film according to claim 4, characterized in that, In step S1, the surface of the substrate is bombarded with low-energy ions. The ion source gas is 99.99% Ar gas, with a working pressure of 0.1 Pa to 5 Pa and a negative bias voltage of -400 to -1000 V. The surface of the substrate is cleaned by glow discharge electricity, and the bombardment time is 20 to 30 minutes; and / or, Steps S1 to S3 are performed at a vacuum degree of 3.0 × 10⁻⁶. -4 ~1.8×10 -3 It was carried out under the condition of Pa.

9. The method for preparing the high-entropy alloy composite film according to claim 4, characterized in that, Before step S1, a pretreatment step is included: first, wiping the surface of the substrate with a degreasing solvent, then immersing the substrate in tetrachloroethylene for 10-30 minutes, followed by ultrasonic cleaning in a metal cleaning agent for 10-20 minutes, and drying; and / or, The step after step S3 also includes a packaging step: the substrate on which the high-entropy alloy composite film is prepared is placed in an ethanol aqueous solution for ultrasonic cleaning for 5-10 minutes, dried, and then vacuum sealed for storage.

10. The application of the high-entropy alloy composite film according to any one of claims 1 to 3 or the high-entropy alloy composite film prepared by the preparation method according to any one of claims 4 to 9 in bearings, gears, blades, and splined shafts.

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