Preparation method of substrate activation assisted aerosol deposition film

Abstract

The invention relates to a method for preparing a substrate activation-assisted aerosol deposition film, which comprises the following steps of: activating a substrate before the aerosol deposition film, namely sequentially performing plasma activation treatment of argon, oxygen and nitrogen at 25 + / -1 DEG C and under the pressure of 50-100Pa, removing organic matters on the surface by argon plasma activation, and removing organic matters on the surface by nitrogen plasma activation. A weak boundary layer is removed to form a certain rough structure, so that the surface area is increased; oxygen plasma generates a large number of polar groups such as hydroxyl on the surface of the substrate; nitrogen plasma nitrides the base material to generate Al-N bonds, so that the surface energy is improved, and a strong interface is formed; experiments prove that compared with an unactivated base material, the bonding strength of the coating subjected to aerosol deposition and the surface of the base material is improved to 33.5 MPa from 17.2 MPa, and an SEM pattern shows that the interface between the activated base material and the coating is clear, the coating is uniform, and the porosity is low.

Description

Technical Field

[0001] This invention relates to the field of low-pressure solid-state high-speed deposition technology, and in particular to a method for preparing substrate-activated aerosol deposition thin films. Background Technology

[0002] Aerosol deposition is a solid-state coating preparation technology. Its core principle is to achieve high-speed deposition of ceramic or metal powders at room temperature or near room temperature. The basic process is as follows: First, micron- or submicron-sized raw material powders are mixed with a carrier gas (such as nitrogen or helium) in an aerosol generation chamber to form an aerosol stream. This aerosol stream is then introduced into a deposition chamber maintained at a low vacuum (typically tens to hundreds of Pascals). Driven by the huge pressure difference between the chamber inlet (nozzle) and the interior, the aerosol particles are accelerated to supersonic speeds. These high-speed solid particles impact the substrate surface with immense kinetic energy. When the kinetic energy of the particles exceeds their critical plastic deformation energy, violent plastic deformation, breakage, and mechanical interlocking and metallurgical bonding occur between particles and between particles and the substrate surface, resulting in layer-by-layer deposition on the substrate to form a dense coating. Unlike traditional thermal spraying techniques (such as plasma spraying), which require heating the powder to a molten or semi-molten state, aerosol deposition does not require an external heat source throughout the entire process, and the powder remains solid. Therefore, it is also considered a derivative or specific form of cold spraying technology. Its significant advantage lies in avoiding problems such as phase transformation, oxidation, and residual stress caused by high temperatures, making it particularly suitable for depositing functional ceramic thick films on heat-sensitive substrates.

[0003] However, this technology faces significant challenges in practical applications, especially when depositing high-hardness ceramic coatings. When preparing yttrium oxide coatings on alumina ceramic substrates via aerosol deposition, the weak adhesion between the coating and substrate, due to both being high-hardness ceramic materials (Mohs hardness between 8 and 9), results in a mechanically dependent bonding effect. From a mechanical bonding perspective, the bonding in aerosol deposition largely relies on plastic deformation caused by particle impact for mechanical anchoring. When high-hardness yttrium oxide particles impact the equally high-hardness alumina substrate, the degree of plastic deformation is limited, leading to weak mechanical interlocking. Secondly, from a physicochemical perspective, ceramic materials typically possess high surface energy and chemical inertness. Especially dense ceramics like alumina and yttrium oxide, which have undergone sintering, exhibit low surface atomic activity and lack active functional groups. Under room-temperature solid-state deposition conditions, effective chemical reactions or diffusion between particles and the substrate are difficult to achieve, hindering the formation of strong chemical bonds (such as covalent or ionic bonds). The interface primarily relies on weak van der Waals forces, resulting in limited bonding strength. Furthermore, during high-speed particle impacts, if the interfacial bonding is weak, some particles may rebound or only undergo brittle fracture rather than effective deposition, further reducing deposition efficiency and coating density. Therefore, direct aerosol deposition between ceramic materials of similar hardness often results in coatings with poor adhesion and easy peeling, greatly limiting the application range of this technology. Effectively activating the surface of inert ceramic substrates, increasing their surface energy, and providing more bonding sites for deposited particles has become crucial for improving coating adhesion. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention proposes a method for preparing substrate-activated aerosol deposition films.

[0005] The technical solution of this invention is as follows: A method for preparing a substrate activation-assisted aerosol deposition film includes the following steps: S1. The substrate deposited by aerosol is subjected to plasma activation treatment with inert gas, oxygen and nitrogen in sequence to obtain the activated substrate; S2. Mix the raw material powder with pressurized carrier gas to form an aerosol, and spray the aerosol onto the activated substrate surface treated in step S1 to obtain a substrate activation-assisted aerosol deposition film.

[0006] Furthermore, the inert gas mentioned in step S1 is Ar.

[0007] Further, in step S1, the plasma power of the inert gas is 50-100W and the activation time is 3-5min; the plasma power of the oxygen is 120-150W and the activation time is 5-7min; and the plasma power of the nitrogen is 80-120W and the activation time is 3-5min.

[0008] Furthermore, the plasma activation treatment with inert gas, oxygen, and nitrogen described in step S1 is carried out at 25±1℃ and 50-100Pa pressure.

[0009] Furthermore, the substrate mentioned in step S1 is Al2O3 ceramic.

[0010] Furthermore, in step S2, the activated substrate is subjected to aerosol spraying within 15 minutes.

[0011] Furthermore, the raw material powder mentioned in step S2 is yttrium oxide powder with a particle size of 0.3-0.5 μm.

[0012] Furthermore, the gas mentioned in step S2 is He, and the technical parameters of the aerosol spraying are: the scanning rate during spraying is 5-20 mm / s, the powder feeding rate is 5-10 g / min, and the distance from the nozzle to the substrate surface is 5-40 mm.

[0013] Furthermore, the aerosol spraying in step S2 is carried out in a deposition chamber at a pressure of 10-1000 Pa.

[0014] Compared with the prior art, the present invention has at least the following advantages: This invention relates to a method for preparing a substrate-activated assisted aerosol deposition film. Before aerosol deposition, the substrate is activated. The substrate activation step involves sequentially performing plasma activation treatments with argon, oxygen, and nitrogen at 25±1℃ and 50-100Pa. Argon plasma activation removes surface organic matter, eliminates weak boundary layers, forms a certain degree of roughness, and increases the surface area. Oxygen plasma generates a large number of polar groups such as hydroxyl groups on the substrate surface. Nitrogen plasma nitrides the substrate, generating Al-N bonds, increasing surface energy, and forming a strong interface. Experiments have shown that, compared to an unactivated substrate, the bonding strength between the aerosol-deposited coating and the substrate surface increases from 17.2MPa to 33.5MPa. SEM images show a clear interface between the activated substrate and the coating, a uniform coating, and low porosity. Attached Figure Description

[0015] To more clearly illustrate the specific embodiments of the present invention, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below.

[0016] Figure 1 This is a SEM image of the cross-section of the ceramic coating prepared in Example 1 of the present invention; Figure 2 This is a SEM image of the cross-section of the ceramic coating prepared in Comparative Example 1 of the present invention. Figure 3This is a SEM image of the cross-section of the ceramic coating prepared in Comparative Example 2 of the present invention. Detailed Implementation

[0017] The present invention will now be described in further detail. It should be noted that the following specific embodiments are only used to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention. Those skilled in the art can make some non-essential improvements and adjustments to the present invention based on the above application content.

[0018] This invention provides a general and / or specific description of the materials and experimental methods used in the experiments. Unless otherwise specified, all experimental or testing methods are conventional methods; all reagents or instruments used, unless otherwise specified, are commercially available conventional products prepared or used using conventional methods.

[0019] Source of materials: Al2O3 ceramic sheets: Purchased from KCM Technology, South Korea, 997 purity Al2O3 ceramic sheets.

[0020] Example 1: Preparation method of substrate activation-assisted aerosol deposition thin film S1. Substrate Activation: Using 45×45mm Al2O3 ceramic sheets as the substrate for aerosol deposition, the Al2O3 ceramic sheets were first ultrasonically cleaned in acetone and anhydrous ethanol for 15 minutes each, and then thoroughly dried in an 80℃ oven. After that, they were subjected to plasma activation treatment in sequence: Ar (100W, 3min) → O2 (150W, 5min) → N2 (120W, 3min). The plasma activation treatment of the substrate was carried out at 25℃ and 50Pa pressure. The activated substrate was transferred into the deposition chamber for aerosol deposition within 15min. S2. Aerosol Deposition: In the aerosol deposition process, He is used as the carrier gas with a flow rate of 50 L / min. The raw material powder is Y2O3 spherical powder with a particle size of 0.5 μm. The carrier gas and the raw material powder form an aerosol in the aerosol generation chamber. The pressure of the aerosol generation chamber is 300 kPa, and the pressure of the deposition chamber is 120 Pa. The activated Al2O3 ceramic sheet is fixed on the XY moving base. The aerosol is sprayed from the nozzle with a distance of 5 mm between the nozzle and the substrate. The spray gun moving speed is 5 mm / s. Experiments are carried out according to the above technical solution to prepare a ceramic coating.

[0021] Example 2: Preparation method of substrate activation-assisted aerosol deposition thin film S1. Substrate Activation: Using 45×45mm Al2O3 ceramic sheets as the substrate for aerosol deposition, the Al2O3 ceramic sheets were first ultrasonically cleaned in acetone and anhydrous ethanol for 15 minutes each, and then thoroughly dried in an 80℃ oven. After that, they were subjected to plasma activation treatment in sequence: Ar (100W, 5min) → O2 (130W, 7min) → N2 (100W, 5min). The plasma activation treatment of the substrate was carried out at 25℃ and 50Pa pressure. The activated substrate was transferred into the deposition chamber for aerosol deposition within 15min. S2. Aerosol Deposition: In the aerosol deposition process, He is used as the carrier gas with a flow rate of 50 L / min. The raw material powder is Y2O3 spherical powder with a particle size of 0.5 μm. The carrier gas and the raw material powder form an aerosol in the aerosol generation chamber. The pressure of the aerosol generation chamber is 300 kPa, and the pressure of the deposition chamber is 120 Pa. The activated Al2O3 ceramic sheet is fixed on the XY moving base. The aerosol is sprayed from the nozzle with a distance of 5 mm between the nozzle and the substrate. The spray gun moving speed is 5 mm / s. Experiments are carried out according to the above technical solution to prepare a ceramic coating.

[0022] Example 3: Preparation method of substrate activation-assisted aerosol deposition thin film S1. Substrate Activation: Using 45×45mm Al2O3 ceramic sheets as the substrate for aerosol deposition, the Al2O3 ceramic sheets were first ultrasonically cleaned in acetone and anhydrous ethanol for 15 minutes each, and then thoroughly dried in an 80℃ oven. After that, they were subjected to plasma activation treatment in sequence: Ar (100W, 3min) → O2 (150W, 5min) → N2 (120W, 3min). The plasma activation treatment of the substrate was carried out at 25℃ and 50Pa pressure. The activated substrate was transferred into the deposition chamber for aerosol deposition within 15min. S2. Aerosol Deposition: In the aerosol deposition process, He is used as the carrier gas with a flow rate of 50 L / min. The raw material powder is Y2O3 spherical powder with a particle size of 0.3 μm. The carrier gas and the raw material powder form an aerosol in the aerosol generation chamber. The pressure of the aerosol generation chamber is 300 kPa, and the pressure of the deposition chamber is 120 Pa. The activated Al2O3 ceramic sheet is fixed on the XY moving base. The aerosol is sprayed from the nozzle with a distance of 5 mm between the nozzle and the substrate. The spray gun moving speed is 5 mm / s. Experiments are carried out according to the above technical solution to prepare a ceramic coating.

[0023] Comparative Example 1 The steps in this application are basically the same as those in Example 1, except that the substrate is not activated. The specific operation is as follows.

[0024] S1. Substrate pretreatment: Using 45×45mm Al2O3 ceramic sheets as the substrate for aerosol deposition, the Al2O3 ceramic sheets were first placed in acetone and anhydrous ethanol for ultrasonic cleaning for 15 minutes each, and then placed in an 80℃ oven for thorough drying before use. S2. Aerosol Deposition: In the aerosol deposition process, He is used as the carrier gas with a flow rate of 50 L / min. The raw material powder is Y2O3 spherical powder with a particle size of 0.3-0.5 μm. The carrier gas and the raw material powder form an aerosol in the aerosol generation chamber. The pressure of the aerosol generation chamber is 300 kPa, and the pressure of the deposition chamber is 120 Pa. The activated Al2O3 ceramic sheet is fixed on the XY moving base. The aerosol is sprayed from the nozzle with a distance of 5 mm between the nozzle and the substrate. The spray gun moving speed is 5 mm / s. Experiments are conducted according to the above technical solution to prepare a ceramic coating.

[0025] Comparative Example 2 The steps in this application are basically the same as those in Embodiment 1, except that the substrate is activated by Ar plasma alone. The specific operation is as follows.

[0026] S1. Substrate activation: Using 45×45mm Al2O3 ceramic sheets as the substrate for aerosol deposition, the Al2O3 ceramic sheets were first ultrasonically cleaned in acetone and anhydrous ethanol for 15 minutes each, and then thoroughly dried in an 80℃ oven. After that, they were subjected to Ar (100W, 3min) plasma activation treatment. The plasma activation treatment of the substrate was carried out at 25℃ and 50Pa pressure. The activated substrate was transferred into the deposition chamber for aerosol deposition treatment within 15 minutes. S2. Aerosol Deposition: In the aerosol deposition process, He is used as the carrier gas with a flow rate of 50 L / min. The raw material powder is Y2O3 spherical powder with a particle size of 0.3-0.5 μm. The carrier gas and the raw material powder form an aerosol in the aerosol generation chamber. The pressure of the aerosol generation chamber is 300 kPa, and the pressure of the deposition chamber is 120 Pa. The activated Al2O3 ceramic sheet is fixed on the XY moving base. The aerosol is sprayed from the nozzle with a distance of 5 mm between the nozzle and the substrate. The spray gun moving speed is 5 mm / s. Experiments are conducted according to the above technical solution to prepare a ceramic coating.

[0027] Comparative Example 3 The steps in this application are basically the same as those in Embodiment 1, except that the substrate is only activated by O2 plasma. The specific operation is as follows.

[0028] S1. Substrate activation: Using 45×45mm Al2O3 ceramic sheets as the substrate for aerosol deposition, the Al2O3 ceramic sheets were first ultrasonically cleaned in acetone and anhydrous ethanol for 15 minutes each, and then thoroughly dried in an 80℃ oven. After that, they were activated by O2 (150W, 5min) plasma. The plasma activation of the substrate was carried out at 25℃ and 50Pa pressure. The activated substrate was transferred into the deposition chamber for aerosol deposition within 15min. S2. Aerosol Deposition: In the aerosol deposition process, He is used as the carrier gas with a flow rate of 50 L / min. The raw material powder is Y2O3 spherical powder with a particle size of 0.3-0.5 μm. The carrier gas and the raw material powder form an aerosol in the aerosol generation chamber. The pressure of the aerosol generation chamber is 300 kPa, and the pressure of the deposition chamber is 120 Pa. The activated Al2O3 ceramic sheet is fixed on the XY moving base. The aerosol is sprayed from the nozzle with a distance of 5 mm between the nozzle and the substrate. The spray gun moving speed is 5 mm / s. Experiments are conducted according to the above technical solution to prepare a ceramic coating.

[0029] Comparative Example 4 The steps in this application are basically the same as those in Embodiment 1, except that the substrate is only activated by N2 plasma. The specific operation is as follows.

[0030] S1. Substrate activation: Using 45×45mm Al2O3 ceramic sheets as the substrate for aerosol deposition, the Al2O3 ceramic sheets were first ultrasonically cleaned in acetone and anhydrous ethanol for 15 minutes each, and then thoroughly dried in an 80℃ oven. After that, they were activated by N2 (120W, 3min) plasma. The plasma activation of the substrate was carried out at 25℃ and 50Pa pressure. The activated substrate was transferred into the deposition chamber for aerosol deposition within 15min. S2. Aerosol Deposition: In the aerosol deposition process, He is used as the carrier gas with a flow rate of 50 L / min. The raw material powder is Y2O3 spherical powder with a particle size of 0.3-0.5 μm. The carrier gas and the raw material powder form an aerosol in the aerosol generation chamber. The pressure of the aerosol generation chamber is 300 kPa, and the pressure of the deposition chamber is 120 Pa. The activated Al2O3 ceramic sheet is fixed on the XY moving base. The aerosol is sprayed from the nozzle with a distance of 5 mm between the nozzle and the substrate. The spray gun moving speed is 5 mm / s. Experiments are conducted according to the above technical solution to prepare a ceramic coating.

[0031] Comparative Example 5 The steps in this application are basically the same as those in Example 1, except that the order of plasma activation is different. Oxygen, nitrogen and argon plasmas are used for activation treatment in sequence. The specific operation is as follows.

[0032] S1. Substrate Activation: Using 45×45mm Al2O3 ceramic sheets as the substrate for aerosol deposition, the Al2O3 ceramic sheets were first ultrasonically cleaned in acetone and anhydrous ethanol for 15 minutes each, and then thoroughly dried in an 80℃ oven. After that, they were subjected to plasma activation treatment in sequence: O2 (150W, 5min) → N2 (120W, 3min) → Ar (100W, 3min). The plasma activation treatment of the substrate was carried out at 25℃ and 50Pa pressure. The activated substrate was transferred into the deposition chamber for aerosol deposition within 15min. S2. Aerosol Deposition: In the aerosol deposition process, He is used as the carrier gas with a flow rate of 50 L / min. The raw material powder is Y2O3 spherical powder with a particle size of 0.3-0.5 μm. The carrier gas and the raw material powder form an aerosol in the aerosol generation chamber. The pressure of the aerosol generation chamber is 300 kPa, and the pressure of the deposition chamber is 120 Pa. The activated Al2O3 ceramic sheet is fixed on the XY moving base. The aerosol is sprayed from the nozzle with a distance of 5 mm between the nozzle and the substrate. The spray gun moving speed is 5 mm / s. Experiments are conducted according to the above technical solution to prepare a ceramic coating.

[0033] Comparative Example 6 The steps in this application are basically the same as those in Example 1, except that the order of plasma activation is different. Argon, nitrogen, and oxygen plasma are used for activation treatment in sequence. The specific operation is as follows.

[0034] S1. Substrate Activation: Using 45×45mm Al2O3 ceramic sheets as the substrate for aerosol deposition, the Al2O3 ceramic sheets were first ultrasonically cleaned in acetone and anhydrous ethanol for 15 minutes each, and then thoroughly dried in an 80℃ oven. After that, they were subjected to plasma activation treatment in sequence: Ar (100W, 3min) → N2 (120W, 3min) → O2 (150W, 5min). The plasma activation treatment of the substrate was carried out at 25℃ and 50Pa pressure. The activated substrate was transferred into the deposition chamber for aerosol deposition within 15min. S2. Aerosol Deposition: In the aerosol deposition process, He is used as the carrier gas with a flow rate of 50 L / min. The raw material powder is Y2O3 spherical powder with a particle size of 0.3-0.5 μm. The carrier gas and the raw material powder form an aerosol in the aerosol generation chamber. The pressure of the aerosol generation chamber is 300 kPa, and the pressure of the deposition chamber is 120 Pa. The activated Al2O3 ceramic sheet is fixed on the XY moving base. The aerosol is sprayed from the nozzle with a distance of 5 mm between the nozzle and the substrate. The spray gun moving speed is 5 mm / s. Experiments are conducted according to the above technical solution to prepare a ceramic coating.

[0035] Test Example 1: Morphology Test SEM images of the cross-sections of the ceramic thin film coatings prepared in Example 1, Comparative Example 1, and Comparative Example 2 are shown below. Figure 1-3 As shown, Figure 1-3 The white section in the middle represents the cross-section of the Y2O3 coating; the upper and lower parts of the Y2O3 coating are the cross-sections of the fixture and the Al2O3 substrate, respectively; from Figure 1 The cross-section of the Y2O3 coating deposited after gradient activation with Ar, O2, and N2 shows a clear, continuous interface between the coating and the Al2O3 substrate, with no visible gaps or cracks. The coating itself is dense and uniform with low porosity. This indicates that gradient activation provides an excellent deposition interface for aerosol particles, promoting particle deformation and bonding. Figure 2 Without plasma activation, the interface between the coating and the substrate is unclear, and fine cracks appear near the top of the coating. The top is loose and the overall density is reduced. Figure 3 The substrate was activated using a single Ar plasma, which improved the interfacial bonding, but the coating density was not as good as in Example 1, and the top of the coating was uneven.

[0036] Test Example 2: Bond Strength The adhesion strength of the coating was tested using an adhesion tester. The adhesion strength data between the yttrium oxide films and the substrates in Examples 1 to 3 and Comparative Examples 1 to 6 are shown in Table 1.

[0037] Table 1. Bond strength of each group of thin film coatings Table 1 shows that after sequential activation of the substrate by Ar, O2, and N2 plasmas, the bonding strength between the yttrium oxide film and the substrate was significantly improved. + Physical bombardment is used to remove surface organic matter, eliminate weak boundary layers, form a certain rough structure, and increase the surface area; O2 plasma generates a large number of polar groups such as hydroxyl groups on the substrate surface; N2 plasma nitrides the substrate, generating Al-N bonds, increasing surface energy, and forming a strong interface. After the plasma activates the substrate surface, low-pressure solid-state high-speed deposition is immediately performed. Yttrium oxide powder impacts the activated substrate surface at high speed, enhancing the adhesion between the ceramic film and the substrate and improving the reliability of the coating. However, changing the order of plasma activation (Comparative Example 6) results in a much lower adhesion strength than that of Example 1, which may be related to the "passivation" effect produced by the final O2 oxidation step. As can be seen from the data in Table 1, the activation of the substrate surface according to the method of this invention produces a synergistic effect among the gases.

[0038] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. 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 therein. Such 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, and they should all be covered within the scope of the claims and specification of the present invention.

Claims

1. A method for the preparation of an activated substrate assisted aerosol deposited thin film, characterized in that, The method comprises the following steps: S1. sequentially performing plasma activation treatment on the aerosol-deposited substrate by inert gas, oxygen, and nitrogen to obtain an activated substrate; S2. mixing raw material powder with pressurized carrier gas to form an aerosol, and spraying the aerosol on the surface of the activated substrate treated in step S1 to obtain a substrate activation-assisted aerosol deposition film.

2. The production method according to claim 1, characterized by, The inert gas in step S1 is Ar.

3. The production method according to claim 2, characterized by, The plasma power of the inert gas in step S1 is 50-100 W, and the activation time is 3-5 min; the plasma power of the oxygen is 120-150 W, and the activation time is 5-7 min; the plasma power of the nitrogen is 80-120 W, and the activation time is 3-5 min.

4. The production method according to claim 3, characterized by, The plasma activation treatment of the inert gas, oxygen, and nitrogen in step S1 is performed at a pressure of 25±1℃ and 50-100 Pa.

5. The production method according to any one of claims 1 to 4, characterized by, The substrate in step S1 is Al2O3 ceramic.

6. The production method according to claim 5, wherein In step S2, the activated substrate is subjected to aerosol spraying within 15 min.

7. The preparation method according to claim 5, characterized in that, The raw material powder in step S2 is yttrium oxide powder with a particle size of 0.3-0.5 μm.

8. The method of claim 1, wherein, The gas in step S2 is He, and the technical parameters of the aerosol spraying are as follows: the scanning speed during spraying is 5-20 mm / s, the powder feeding amount is 5-10 g / min, and the distance from the nozzle to the substrate surface is 5-40 mm.

9. The method of claim 1, wherein, The aerosol spraying in step S2 is performed in a deposition chamber, and the pressure of the deposition chamber is 10-1000 Pa.

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