Preparation method of ion-assisted aerosol deposition ceramic film coating

Abstract

The invention relates to a preparation method of an ion-assisted aerosol deposition ceramic film coating, the preparation method uses a mixed gas of argon and helium as a current-carrying gas and an ionization gas, the mass of He atoms is light, and the movement speed of light gas molecules is faster, so that momentum can be more effectively transferred to ceramic particles to be deposited, and the deposition efficiency is improved. The acceleration effect of the particles is improved, so that the high-speed particles deform at the moment of impacting the base material, and a compact structure is formed; ar is inert gas, argon is heavy inert gas, Ar < + > generated by Ar has a good tamping effect on the coating, the densification of the coating is improved, and experiments prove that the porosity of the ceramic film coating prepared by the method is smaller than 0.1%, the bonding strength with a base material is 25.6-30.6 MPa, the hardness is 983.7-105.2 N / mm < 2 >, a mutual promotion effect is generated, and fusion and densification of a particle interface are facilitated.

Description

Technical Field

[0001] This invention belongs to the field of aerosol deposition technology, and in particular relates to a method for preparing an ion-assisted aerosol deposition ceramic thin film coating. Background Technology

[0002] Aerosol deposition is a solid-state deposition technique that forms coatings by impacting a substrate with airborne particles in a vacuum or low-pressure environment. The basic process involves mixing micron- or submicron-sized ceramic powder with an inert gas to form an aerosol. Under pressure differential, this aerosol is accelerated through a nozzle and impacts the substrate surface at high speed. The particles undergo plastic deformation or breakage upon impact, accumulating layer by layer to form a coating. This technique is applicable to a variety of ceramic materials, can achieve coating preparation at low temperatures, avoiding material phase transformations or thermal damage, and is suitable for temperature-sensitive substrates. However, traditional aerosol deposition techniques often encounter problems such as weak coating adhesion, numerous internal pores, and non-dense structures when processing high-hardness, high-brittle ceramic materials, affecting the mechanical properties and service life of the coating.

[0003] Currently, methods to improve coating quality mainly include substrate heating and post-coating treatment. While these methods improve coating quality to some extent, they do not significantly improve issues such as high internal porosity, low bonding strength, and low deposition efficiency in ceramic coatings with high deposition hardness. Ion-assisted enhanced aerosol deposition is a composite technology that introduces a plasma bombardment mechanism to improve coating quality based on traditional aerosol deposition. This technology uses a plasma generator in the deposition chamber to ionize part of the process gas into plasma, and applies a negative bias electric field to the substrate, causing positively charged ions to continuously bombard the surface of the depositing coating under the influence of the electric field. This bombardment process can compact the deposited layer, reduce porosity, enhance the bonding force between particles and between particles and the substrate, and further improve the density and bonding strength of the coating. However, in actual experiments, the effect of a single high-pressure carrier gas on improving coating performance is still limited, and there is an urgent need to develop a new method for preparing ion-assisted enhanced thin film coatings. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention proposes a method for preparing ion-assisted aerosol deposition ceramic thin film coatings.

[0005] The technical solution of this invention is as follows: A method for preparing an ion-assisted aerosol deposition ceramic thin film coating includes the following steps: S1. A mixed inert gas is used as a carrier gas, and the carrier gas is mixed with the raw material powder to form an aerosol; S2. After the carrier gas in the aerosol is ionized, the raw material powder is sprayed onto the surface of the substrate along with the ionized carrier gas to form a ceramic thin film coating.

[0006] Furthermore, the mixed inert gas mentioned in step S1 is a mixture of argon and helium.

[0007] Furthermore, in the argon and helium gas, the atomic ratio of argon atoms to helium atoms is (1-3):(1-3).

[0008] Furthermore, the raw material powder mentioned in step S1 is yttrium oxide powder.

[0009] Furthermore, the raw material powder mentioned in step S1 is submicron in size.

[0010] Furthermore, the aerosol is electrostatically dispersed before the carrier gas is ionized in step S2.

[0011] Furthermore, in step S2, a negative bias electric field is provided on the surface of the substrate, wherein the negative bias voltage is 50-200V.

[0012] Furthermore, the technical parameters for spraying in step S2 are as follows: 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 in step S1 is stored in an aerosol generation chamber, and the pressure of the aerosol generation chamber is 0.2-0.5 MPa.

[0014] Furthermore, the spraying operation in step S2 is carried out in a deposition chamber at a pressure of 10-1000 Pa.

[0015] Compared with the prior art, the present invention has at least the following advantages: This invention relates to a method for preparing a ceramic thin film coating by ion-assisted aerosol deposition. The method includes the following steps: using a mixed inert gas as a carrier gas, the carrier gas is mixed with raw material powder to form an aerosol; then, after ionizing the carrier gas in the aerosol, the raw material powder is sprayed onto the surface of a substrate along with the ionized carrier gas to form a ceramic thin film coating. The method uses a mixture of argon and helium as both the carrier gas and the ionizing gas. Helium atoms are relatively light, and lighter gas molecules move faster, more effectively transferring momentum to the ceramic particles to be deposited, which is beneficial for improving the particle acceleration effect, causing deformation of the high-speed particles upon impact with the substrate, forming a dense structure. Argon, on the other hand, is a heavier inert gas, and Ar2+ produces Ar2+. + The method described in this invention effectively compacts the coating, enhancing its density. Experimental results show that the ceramic thin film coating prepared by this method has a porosity of less than 0.1%, a bonding strength with the substrate of 25.6-30.6 MPa, and a hardness of 983.7-1055.2 N / mm². 2This creates a mutually reinforcing effect, which helps the particle interface to fuse and densify. Attached Figure Description

[0016] 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.

[0017] Figure 1 This is a schematic diagram of the spraying equipment for the ion-assisted reinforced ceramic thin film coating of this application.

[0018] Explanation of reference numerals in the attached drawings: 1. Gas supply device; 2. Aerosol generation chamber; 3. Nozzle; 4. Plasma generator; 5. Deposition chamber; 6. First pipe; 7. Second pipe; 8. Substrate; 9. Electrostatic dispersion device; 10. Pressure gauge; 11. Filter; 12. Vacuum pump assembly; 13. XYZ stage; 14. Electrode plate. Detailed Implementation

[0019] 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.

[0020] 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.

[0021] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" or "several" means two or more, unless otherwise explicitly specified.

[0022] like Figure 1 The diagram shows a schematic of the spraying equipment for ion-assisted aerosol deposition of ceramic thin film coatings according to the present invention. The spraying equipment includes a gas supply device 1, an aerosol generation chamber 2, a nozzle 3, a plasma generator 4, and a deposition chamber 5. The nozzle 3 and the plasma generator 4 are disposed in the deposition chamber 5. The gas supply device 1 and the aerosol generation chamber 2 are connected by a first pipe 6, and a flow meter is installed on the first pipe 6. The aerosol generation chamber 2 and the deposition chamber 5 are connected by a second pipe 7, and a pressure gauge 10 and a filter 11 are installed on the second pipe 7.

[0023] The gas supply device 1 is used to supply pressurized carrier gas to the aerosol generation chamber 2. In this invention, the carrier gas is a mixture of helium and argon.

[0024] The aerosol generation chamber 2 is used to mix pressurized carrier gas and raw material powder to form an aerosol. In this invention, the pressure of the aerosol generation chamber 2 is 0.2-0.5 MPa.

[0025] The plasma generator 4 is disposed in the deposition chamber 5 and is used to ionize the carrier gas in the aerosol output from the nozzle 3 into ionized gas. A vacuum pump group 12 is disposed outside the deposition chamber 5. The deposition chamber 5 is connected to the vacuum pump group 12 through a pipeline, so that the deposition chamber 5 is a low-pressure environment. The deposition chamber 5 is used to deposit a thin film layer of ion-assisted aerosol on the surface of the substrate 8. In this invention, the pressure in the deposition chamber 5 is 10-1000 Pa. The deposition chamber 5 is also provided with an XYZ stage 13, an electrode plate 14, and a substrate 8. The electrode plate 14 is mounted on the XYZ stage 13 and is used to set a negative bias electric field on the surface of the substrate 8. The XYZ stage 13 drives the substrate 8 to move in the XY direction of the XY plane.

[0026] The spraying equipment also includes an electrostatic dispersion device 9, which is installed on the second pipe 7. When the carrier gas (Ar / He mixture) in the aerosol generation chamber 2 carries ceramic powder through the device, the particles will rub or be induced by the charged electrodes to acquire the same polarity of charge. The particles can effectively overcome the inherent van der Waals forces and other attractive forces between powder particles, break up the agglomerates during the conveying process, keep the particles in the aerosol in a highly dispersed and uniform state, and ensure the uniformity of powder feeding.

[0027] The working process and principle of the spraying equipment are as follows: The gas supply device 1 contains a mixed high-pressure carrier gas of Ar and He. The high-pressure carrier gas and raw material powder are mixed and blown into an aerosol in the aerosol generation chamber 2. The deposition chamber 5 is under low-pressure vacuum conditions. After the aerosol powder is dispersed by the electrostatic dispersion device 9, the raw material powder is first brought to a supersonic state using pressure difference and a specially structured nozzle. Then, the plasma generator 4 ionizes the carrier gas into positively charged plasma. The negative bias electric field distributed around the substrate 8 causes the high-speed raw material powder particles to collide with the substrate 8, resulting in strong plastic deformation and stacking deposition on the surface of the substrate 8. The He molecules in the mixed high-pressure carrier gas are lightweight and have a good acceleration effect on the particles, forming Ar... + The two molecules work synergistically to significantly improve the density of the ceramic film and reduce its porosity. Specific effects are shown in the following examples and comparative examples.

[0028] Example 1 This embodiment describes a method for preparing a ceramic thin film coating using the spraying equipment of the present invention, with the specific parameters as follows.

[0029] The atomic ratio of Ar:He in the mixed carrier gas is 1:1. The raw material powder is spherical yttrium oxide particles with a particle size of 400 nm. The pressure in the aerosol generation chamber is 0.3 MPa, the pressure in the deposition chamber is 500 Pa, the scanning rate is 5 mm / s, the powder feed rate is 5 g / min, the distance from the nozzle to the substrate surface is 10 mm, and the deflection voltage is 100 V.

[0030] Example 2 This embodiment describes a method for preparing a ceramic thin film coating using the spraying equipment of the present invention, with the specific parameters as follows.

[0031] The atomic ratio of Ar:He in the mixed carrier gas is 1.3:1. The raw material powder is spherical yttrium oxide particles with a particle size of 400 nm. The pressure in the aerosol generation chamber is 0.3 MPa, the pressure in the deposition chamber is 500 Pa, the scanning rate is 5 mm / s, the powder feed rate is 5 g / min, the distance from the nozzle to the substrate surface is 10 mm, and the deflection voltage is 100 V.

[0032] Example 3 This embodiment describes a method for preparing a ceramic thin film coating using the spraying equipment of the present invention, with the specific parameters as follows.

[0033] The atomic ratio of Ar:He in the mixed carrier gas is 1:2.5. The raw material powder is spherical yttrium oxide particles with a particle size of 400 nm. The pressure in the aerosol generation chamber is 0.3 MPa, the pressure in the deposition chamber is 500 Pa, the scanning rate is 5 mm / s, the powder feed rate is 5 g / min, the distance from the nozzle to the substrate surface is 10 mm, and the deflection voltage is 100 V.

[0034] Comparative Example 1 This comparative example is basically the same as Example 1, except that only Ar is used as the carrier gas and ionization gas. The specific parameters are as follows.

[0035] The carrier gas is Ar, the raw material powder is spherical yttrium oxide particles with a particle size of 400 nm, the pressure of the aerosol generation chamber is 0.3 MPa, the pressure of the deposition chamber is 500 Pa, the scanning rate is 5 mm / s, the powder feed rate is 5 g / min, the distance from the nozzle to the substrate surface is 10 mm, and the deflection voltage is 100 V.

[0036] Comparative Example 2 This comparative example is basically the same as Example 1, except that only Ar is used as the carrier gas, and the specific parameters are as follows.

[0037] The carrier gas is Ar, the raw material powder is spherical yttrium oxide particles with a particle size of 400 nm, the pressure of the aerosol generation chamber is 0.3 MPa, the pressure of the deposition chamber is 500 Pa, the scanning rate is 5 mm / s, the powder feed rate is 5 g / min, and the distance from the nozzle to the substrate surface is 10 mm.

[0038] Comparative Example 3 This comparative example is basically the same as Example 1, except that only He is used as the carrier gas and ionization gas. The specific parameters are as follows.

[0039] The carrier gas is He, the raw material powder is spherical yttrium oxide particles with a particle size of 400 nm, the pressure of the aerosol generation chamber is 0.3 MPa, the pressure of the deposition chamber is 500 Pa, the scanning rate is 5 mm / s, the powder feed rate is 5 g / min, the distance from the nozzle to the substrate surface is 10 mm, and the deflection voltage is 100 V.

[0040] Comparative Example 4 This comparative example is basically the same as Example 1, except that only He is used as the carrier gas, and the specific parameters are as follows.

[0041] The carrier gas is He, the raw material powder is spherical yttrium oxide particles with a particle size of 400 nm, the pressure of the aerosol generation chamber is 0.3 MPa, the pressure of the deposition chamber is 500 Pa, the scanning rate is 5 mm / s, the powder feed rate is 5 g / min, and the distance from the nozzle to the substrate surface is 10 mm.

[0042] Comparative Example 5 This comparative example is basically the same as Example 1, except that only air is used as the carrier gas, and the specific parameters are as follows.

[0043] The carrier gas is air, the raw material powder is spherical yttrium oxide particles with a particle size of 400 nm, the pressure of the aerosol generation chamber is 0.3 MPa, the pressure of the deposition chamber is 500 Pa, the scanning rate is 5 mm / s, the powder feed rate is 5 g / min, and the distance from the nozzle to the substrate surface is 10 mm.

[0044] Test case The porosities of Examples 1-3 and Comparative Examples 1-5 are shown in Table 1. Comparative Examples 3-5 show that helium, as both a carrier gas and an ionizing gas, increases the coating density by 0.8%, the bonding strength with the substrate by 6.1 MPa, and the coating hardness by 255 HV. Comparative Examples 1, 2, and 5 show that argon, as both a carrier gas and an ionizing gas, increases the coating density by 0.4%, the bonding strength with the substrate by 3.5 MPa, and the coating hardness by 138 HV. Examples 1-3 show that He atoms are relatively light, and the faster movement of light gas molecules allows for more effective transfer of momentum to the ceramic particles to be deposited, improving particle acceleration and causing deformation upon impact with the substrate, resulting in a dense structure. Argon, being a heavier inert gas, produces Arp... + The method effectively compacts the coating, enhancing its density. When argon and helium are used as a mixed carrier gas, they mutually promote each other, contributing to the fusion and densification of the particle interface. The ceramic thin film coatings prepared in Examples 1 to 3 have a porosity of less than 0.05%, a bonding strength with the substrate of 25.6-30.6 MPa, and a hardness of 983.7-1055.2 HV. These effects are far superior to those produced by using a single ionized gas. Therefore, the method described in this invention demonstrates the synergistic effect of argon and helium.

[0045] Table 1. Porosity of the cross-sections of the ceramic thin film coatings prepared in Examples 1-3 and Comparative Examples 1-5 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 of producing an ion assisted aerosol deposited ceramic thin film coating, characterized in that, The method comprises the following steps: S1. mixing inert gas as carrier gas, which is mixed with raw material powder to form aerosol; S2. after ionizing the carrier gas in the aerosol, the raw material powder is sprayed to the surface of the substrate with the ionized carrier gas to form ceramic thin film coating.

2. The production method according to claim 1, characterized by, The mixed inert gas in step S1 is a mixture of argon and helium.

3. The production method according to claim 2, characterized by, The atomic ratio of argon atoms to helium atoms in the argon and helium is (1-3):(1-3).

4. The production method according to claim 1, characterized by, The raw material powder in step S1 is yttrium oxide powder.

5. The preparation method according to claim 2, characterized in that, The raw material powder in step S1 is submicron.

6. The production method according to any one of claims 1 to 5, characterized by, The aerosol is electrostatically dispersed before ionization of the carrier gas in step S2.

7. The production method according to claim 6, wherein The substrate surface in step S2 is provided with a negative bias electric field, and the negative bias is 50-200V.

8. The production method according to claim 7, characterized by, The technical parameters of the spraying in step S2 are as follows: the scanning speed during spraying is 5-20mm / s, the powder feeding amount is 5-10g / min, and the distance from the nozzle to the substrate surface is 5-40mm.

9. The production method according to claim 7 or 8, characterized by, The aerosol in step S1 is stored in an aerosol generating chamber, and the pressure of the aerosol generating chamber is 0.2-0.5MPa.

10. The production method according to claim 7 or 8, characterized by, The spraying operation in step S2 is carried out in a deposition chamber, and the pressure of the deposition chamber is 10-1000Pa.

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