Preparation method of super-hydrophobic armored TC4 titanium alloy material

Abstract

This invention relates to a method for preparing a superhydrophobic armored TC4 titanium alloy material, comprising the following steps: pretreatment of the surface of a TC4 titanium alloy substrate; armoring the surface of the TC4 titanium alloy substrate; further pretreatment of the TC4 titanium alloy substrate surface by electrodeposition to prepare a deposition layer on the TC4 titanium alloy substrate surface; and drying the TC4 titanium alloy substrate surface to obtain the superhydrophobic armored TC4 titanium alloy material. This preparation method effectively improves the contact characteristics between the TC4 titanium alloy material and droplets; the armored microstructure increases the contact area between the coating and the substrate, forming a mechanical interlocking structure and enhancing the adhesion strength between the deposition layer and the TC4 titanium alloy material. Furthermore, the armored microstructure can protect the surface of the TC4 titanium alloy material under mechanical friction conditions, achieving the goals of superhydrophobicity, wear resistance, and frost resistance. The preparation process is simple and controllable, and has good application potential in low-temperature, icing-prone fields such as aerospace and rail transportation.

Description

Technical Field

[0001] This invention belongs to the field of material surface treatment technology, and relates to the surface treatment of TC4 titanium alloy materials, especially a method for preparing superhydrophobic armored TC4 titanium alloy materials. Background Technology

[0002] In the existing aerospace industry technology system, TC4 titanium alloy, due to its core advantages such as high strength, low density, excellent corrosion resistance, and fatigue resistance, is widely used in many critical load-bearing and aerodynamic components of civil aircraft, especially core components such as the engine leading edge lip that directly bear the impact of airflow and environmental corrosion. However, during actual aircraft operation, critical parts such as the engine leading edge lip are highly susceptible to icing due to environmental conditions such as high-altitude low temperatures and humidity changes. Once icing occurs, it can damage the aerodynamic shape of the structure, leading to a series of serious flight safety problems. Therefore, how to improve the anti-icing effect of materials is an urgent problem to be solved. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method for preparing a structurally stable and highly efficient anti-icing superhydrophobic armored TC4 titanium alloy material.

[0004] To solve the above problems, the technical solution of the present invention is as follows:

[0005] A method for preparing a superhydrophobic armored TC4 titanium alloy material includes the following steps:

[0006] The surface of the TC4 titanium alloy substrate is pretreated;

[0007] The surface of the TC4 titanium alloy substrate is armored;

[0008] The TC4 titanium alloy substrate was subjected to electrodeposition pretreatment again to prepare a deposition layer on the TC4 titanium alloy substrate surface;

[0009] The surface of TC4 titanium alloy substrate is dried to obtain superhydrophobic armored TC4 titanium alloy material.

[0010] In a further embodiment, the surface of the TC4 titanium alloy substrate is armored, specifically including:

[0011] Laser processing is performed on the surface of TC4 titanium alloy substrate to form a grid pattern on the surface of TC4 titanium alloy substrate.

[0012] In a further embodiment, a nanosecond pulsed laser with a wavelength of 1064 nanometers is used to laser process the surface of the TC4 titanium alloy substrate.

[0013] In a further embodiment, the laser processing has a scanning speed of 300 mm / s, a scanning frequency of 50 kHz, a pulse width of 1 μs, a power of 8 W, a processing number of 10 times, and a laser spacing of 72 μm.

[0014] In a further embodiment, the TC4 titanium alloy substrate surface is subjected to electrodeposition pretreatment again to prepare a deposition layer on the TC4 titanium alloy substrate surface, specifically including:

[0015] Electrodeposition was performed in an electrodeposition solution using a TC4 titanium alloy substrate as the cathode and a pure nickel sheet as the anode.

[0016] After electrodeposition, nickel complex deposited particles adhere to the surface of the TC4 titanium alloy substrate.

[0017] In a further embodiment, during electrodeposition, the cathode current density is 3.5 A / dm², the electrodeposition solution temperature is 70°C, and the process lasts for fifteen minutes.

[0018] In a further embodiment, the electrodeposition solution is:

[0019] Add NiCl2·6H2O and myristic acid to anhydrous ethanol and mechanically stir for 30 minutes at a constant temperature.

[0020] In a further embodiment, the concentration of NiCl2·6H2O was 22 g / L, the concentration of myristic acid was 25 g / L, and the constant temperature was 70 °C.

[0021] The mechanical stirring uses a magnetic rotor and is performed at a speed of 60 r / min.

[0022] In a further embodiment, the TC4 titanium alloy substrate surface is subjected to electrodeposition pretreatment again to prepare a deposition layer on the TC4 titanium alloy substrate surface, which further includes:

[0023] Electrodeposition pretreatment is as follows:

[0024] The TC4 titanium alloy substrate was immersed in a 10wt.% HCl solution for forty seconds, then ultrasonically cleaned with deionized water for ten minutes, and finally dried with nitrogen.

[0025] In a further embodiment, the surface of the TC4 titanium alloy substrate is dried to obtain a superhydrophobic armored TC4 titanium alloy material, specifically including:

[0026] The TC4 titanium alloy substrate was dried at 60°C for twelve hours and then cooled to room temperature.

[0027] Compared with the prior art, the beneficial effects of the present invention are:

[0028] 1. This preparation method effectively improves the contact characteristics between TC4 titanium alloy and droplets, significantly reducing droplet wetting. TC4 titanium alloy has a highly inert surface, making the adhesion of the electrodeposited layer prone to insufficient strength. The armored microstructure increases the contact area between the coating and the substrate, forming a mechanical interlocking structure and enhancing the adhesion strength between the deposited layer and the TC4 titanium alloy. Furthermore, the armored microstructure can protect the surface of the TC4 titanium alloy under mechanical friction conditions, effectively reducing the frictional loss of the nano-deposited layer and achieving the goals of superhydrophobicity, wear resistance, and frost resistance on the TC4 titanium alloy surface. The preparation process is simple and controllable, showing good application potential in low-temperature, icing-prone fields such as aerospace and rail transportation.

[0029] 2. This preparation method fully considers the intrinsic characteristic of TC4 titanium alloy, which has a relatively low thermal conductivity. Using high-power lasers for surface processing can easily lead to defects such as surface erosion and hot cracking, disrupting the structural continuity and integrity of the armor texture and thus weakening the mechanical protective effect of the armored structure. By synergistically controlling the intensity and pulse width of medium-to-low power lasers, a micron-scale armor texture is constructed on the surface of TC4 titanium alloy while avoiding thermal damage from high-power lasers. This micro-nano composite structure combines excellent mechanical stability with the micro-nano composite configuration, satisfying the interface morphology requirements for superhydrophobic functionality while ensuring the structural strength of the armored design, ultimately achieving synergistic optimization of the material's surface functional properties and mechanical properties.

[0030] 3. Under the conditions of ambient temperature of -10℃ and relative humidity of 65%, the untreated TC4 titanium alloy material prepared by this method can freeze in 30 seconds, while the treated armored superhydrophobic TC4 titanium alloy material can freeze for up to 633 seconds. Its freezing time is 21 times longer than that of the untreated TC4 substrate, and it has excellent anti-freezing performance.

[0031] 4. The armored structure of this preparation method is an important component of the multi-level surface morphology. Laser microtexturing not only constructs a micron-level structure on the surface of TC4 titanium alloy to capture air layers and increase the surface's hydrophobicity, but also enhances the adhesion between the electrodeposited layer and the TC4 titanium alloy through morphology optimization, while simultaneously constructing a special micron-level structure and protecting the electrodeposited material. The mechanical stability of the prepared TC4 titanium alloy surface is significantly better than that of untreated TC4 titanium alloy: a 200 g weight was placed and fixed on the TC4 titanium alloy and moved 10 cm horizontally and vertically on 1000-grit SiC sandpaper, forming one cycle. After 50 wear cycles, most of the electrodeposited material remained adhered to the TC4 titanium alloy surface. Furthermore, after 50 tape peeling experiments, the TC4 titanium alloy surface still maintained its superhydrophobic properties.

[0032] 5. This preparation method utilizes fluorine-free surface energy-modifying materials and can be completed in a single electrodeposition process. The micro-nano structure of the superhydrophobic armored TC4 titanium alloy surface endows it with self-cleaning capabilities, effectively preventing surface contamination and maintaining its superhydrophobic properties. Furthermore, it offers advantages such as simple preparation process and environmental friendliness. Attached Figure Description

[0033] Figure 1 A flowchart of a method for preparing a superhydrophobic armored TC4 titanium alloy material;

[0034] Figure 2 A schematic diagram of laser microtexturing for a method of preparing superhydrophobic armored TC4 titanium alloy material;

[0035] Figure 3 A schematic diagram of electrodeposition for a method of preparing a superhydrophobic armored TC4 titanium alloy material;

[0036] Figure 4 The surface microstructure of a method for preparing a superhydrophobic armored TC4 titanium alloy material is shown in the image.

[0037] Figure 5 The image shows the surface static wettability test results of a preparation method for a superhydrophobic armored TC4 titanium alloy material.

[0038] Figure 6 Surface elemental analysis results for a method of preparing a superhydrophobic armored TC4 titanium alloy material;

[0039] Figure 7 The image shows the surface icing experimental results of a method for preparing a superhydrophobic armored TC4 titanium alloy material.

[0040] Figure 8 The image shows the surface frosting test results of a method for preparing a superhydrophobic armored TC4 titanium alloy material.

[0041] Figure 9 The image shows the surface wear test results of a method for preparing a superhydrophobic armored TC4 titanium alloy material.

[0042] Figure 10 The image shows the surface wear test results of a method for preparing a superhydrophobic armored TC4 titanium alloy material.

[0043] Figure 11 The image shows the results of a tape peeling test for a method of preparing a superhydrophobic armored TC4 titanium alloy material. Detailed Implementation

[0044] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0045] Aircraft flight safety is the core prerequisite and primary goal of civil aviation operations, and is affected by a variety of environmental and structural performance factors. Among them, the icing problem at the leading edge lip of the engine has become one of the key hidden dangers threatening aircraft flight safety, and urgently needs to be effectively solved.

[0046] In the existing aerospace industry technology system, TC4 titanium alloy material is widely used in many key load-bearing and aerodynamic parts of civil aircraft due to its core advantages such as high strength, low density, excellent corrosion resistance, and fatigue resistance, especially core components such as the engine leading edge lip that are directly subjected to airflow impact and environmental corrosion. However, during actual aircraft operation, the engine leading edge lip is highly susceptible to icing due to environmental conditions such as high-altitude low temperatures and humidity changes. Once icing occurs in this area, it directly disrupts the aerodynamic shape of the engine intake, leading to a series of serious flight safety problems. Currently, anti-icing technologies for titanium alloy materials used in the engine leading edge lip still have many shortcomings, and existing solutions are unable to achieve long-term and stable anti-icing effects while ensuring the original mechanical properties of the material.

[0047] Therefore, developing a highly efficient anti-icing technology adapted to titanium alloy materials for the leading edge lip of engines to prevent icing at its source and ensure aircraft flight safety has become a pressing technical challenge in the current aviation industry. This invention uses TC4 titanium alloy as a substrate and proposes a method for preparing a superhydrophobic armored TC4 titanium alloy material, enabling the material to maintain its effectiveness even when structurally damaged. A grid-shaped armor structure is constructed on the substrate surface using laser microtexturing technology, enhancing the wear resistance of the TC4 titanium alloy and improving its adhesion to the electrodeposited layer. This armored structure is then combined with a myristic acid-modified nickel electrodeposition process to prepare a superhydrophobic armored surface. This overcomes the technical bottleneck of insufficient mechanical / environmental durability of superhydrophobic surfaces, improves the anti-icing capability of TC4 titanium alloy, and promotes the application of superhydrophobic surfaces in aircraft anti-icing and de-icing.

[0048] Example 1:

[0049] A method for preparing a superhydrophobic armored TC4 titanium alloy material, such as Figures 1 to 11 As shown, it includes the following steps:

[0050] Step S101: Pre-treat the surface of the TC4 titanium alloy substrate:

[0051] The TC4 titanium alloy substrate was laser-cut into small pieces measuring 20mm × 40mm × 2mm. These pieces were then successively polished with SiC sandpaper of various grits: 60 grit, 400 grit, 800 grit, 1200 grit, 1500 grit, and 2000 grit. Pure nickel sheets were then prepared for later use. These were laser-cut into small pieces measuring 40mm × 40mm × 2mm, and subsequently polished with SiC sandpaper of the same grits.

[0052] The polished TC4 titanium alloy substrate and pure nickel sheet were sequentially immersed in deionized water, anhydrous ethanol, and acetone for ultrasonic cleaning, each for 10 minutes. After removal, they were dried with nitrogen gas to finally obtain a clean and flat TC4 titanium alloy substrate and pure nickel sheet.

[0053] Step S103: Armor the surface of the TC4 titanium alloy substrate:

[0054] like Figure 2As shown, a TC4 titanium alloy substrate was placed on a laser stage, and a 1064nm nanosecond pulsed laser was used to laser process the polished TC4 titanium alloy substrate. During processing, a cross-scanning method with equal spacing in both the horizontal and vertical directions was adopted. The laser scanning speed was 300mm / s, the scanning frequency was 50kHz, the pulse width was 1μs, and the power was 8W. The processing was repeated 10 times, with a spacing of 72μm between adjacent laser beams, and the scanning path was a crisscross pattern. After processing, the TC4 titanium alloy substrate was cleaned in an ultrasonic cleaner with deionized water and anhydrous ethanol for 10 minutes each. Figure 2 This is a schematic diagram of laser microtexturing, including the control system, laser source, and processing path. The red box shows the processing path, indicating that the processing path is crisscrossed.

[0055] Step S105: Perform electrodeposition pretreatment on the surface of the TC4 titanium alloy substrate again to prepare a deposition layer on the surface of the TC4 titanium alloy substrate:

[0056] Pretreatment was performed on the armored TC4 titanium alloy substrate before electrodeposition. The TC4 titanium alloy substrate was briefly immersed in a 10 wt.% HCl solution for 40 seconds to remove the TiO2 oxide film and impurities on the surface. The presence of TiO2 oxide film on the TC4 titanium alloy substrate surface would reduce the adhesion of the electrodeposited layer. The weak acid pickling pretreatment is a prerequisite for the preparation of superhydrophobic armored surfaces using laser microtexture coupled electrodeposition technology. After pickling, the substrate was ultrasonically cleaned with deionized water for 10 minutes to remove residual pickling solution. After cleaning, the TC4 titanium alloy substrate was dried with nitrogen gas and stored.

[0057] like Figure 3 As shown, a surface deposition layer was prepared using electrodeposition technology. The electrodeposition solution was prepared as follows: 22 g / L NiCl2·6H2O and 25 g / L myristic acid were added to anhydrous ethanol. The solution was mechanically stirred at 60 r / min for 30 min in a constant temperature water bath at 70 °C using a magnetic rotor to obtain the electrodeposition solution. A TC4 titanium alloy substrate was then fixed with electrode clamps as the cathode, and a pure nickel sheet electrode was fixed with electrode clamps as the anode. The cathode and anode were inserted into the electrodeposition solution with a 2 cm gap, and electrodeposition was performed continuously for 1 min. During electrodeposition, the cathode current density was 3.5 A / dm³. 2 The electrodeposition solution temperature was maintained at 70℃ for 15 minutes. A magnetic rotor was placed in the electrodeposition solution for mechanical stirring at 60 r / min. After deposition, the TC4 titanium alloy substrate was removed and cooled to room temperature. Surface impurities were cleaned with deionized water, and then the substrate was dried in an oven at 60℃ for 6 hours to obtain the desired product. Figure 4 (a) and Figure 4 (b) shows the surface microstructure of the TC4 titanium alloy substrate. Figure 3This is a schematic diagram of electrodeposition. The anode material on the left is a pure nickel sheet, and the cathode material on the right is a TC4 titanium alloy substrate. During the deposition process, nickel ions in the pure nickel sheet continuously move towards the cathode surface, and myristic acid ions in the electrodeposition solution adhere to the cathode surface, making the deposition reaction products on the cathode surface nickel, nickel and myristic acid complexes, and continuously releasing hydrogen gas during the deposition process.

[0058] Figure 4 (a) – Figure 4 (j) are scanning electron microscope (SEM) images showing the changes in cathode surface morphology at different deposition times (1, 5, 10, 15, and 20 minutes). It can be observed that nanoscale particles formed by deposition cover the armored structure surface of the TC4 titanium alloy substrate and couple with the armored structure constructed through laser processing, forming a multi-level micro / nanostructure surface. At 1 minute of electrodeposition, the surface of the TC4 titanium alloy substrate is relatively smooth, and the deposits are sparsely distributed, forming an initial sparse thin layer. This represents the initial growth stage of the deposits, such as... Figure 4 (b) shows a magnified SEM image. As the electrodeposition time increased from 5 minutes to 15 minutes, a more regular and uniform cauliflower-like microstructure formed on the surface of the TC4 titanium alloy substrate. The rough surface was covered with sharp spikes, and there were numerous cracks between the spikes, which effectively trapped a large amount of air. The presence of an air layer on the surface of the TC4 titanium alloy substrate has been shown to reduce the contact area between the sample surface and the liquid, prevent suspended droplets from penetrating the surface, and give the surface superhydrophobic properties. However, with increasing electrodeposition time, the particle diameter increases, and the electrodeposited film becomes thicker, such as... Figure 4 (i) Figure 4 As shown in (j), when the electrode deposition process continues for 20 minutes, the spikes become increasingly dense, leading to a decrease in porosity and a reduction in trapped air. This phenomenon may adversely affect the superhydrophobic properties of the TC4 titanium alloy substrate surface.

[0059] During electrodeposition, hydrogen ions (H+) near the cathode gain electrons and undergo a chemical reaction to generate hydrogen gas (H2). The released hydrogen gas helps form a more porous surface microstructure. This unique structure traps air bubbles upon droplet contact, creating a cushion effect that enhances the hydrophobic properties of the TC4 titanium alloy substrate surface. The chemical reaction occurring on the TC4 titanium alloy substrate during electrodeposition can be represented by the following equation:

[0060] ;

[0061] ;

[0062] ;

[0063] Step S107: Dry the surface of the TC4 titanium alloy substrate to obtain superhydrophobic armored TC4 titanium alloy material.

[0064] The electrodeposited TC4 titanium alloy substrate was placed in a constant-temperature drying oven and dried at 60°C for 12 hours, then cooled to room temperature to obtain a superhydrophobic armored TC4 titanium alloy material. The surface of the TC4 titanium alloy material exhibits a grid-like micro-nano composite structure, with cauliflower-like micron-sized particles attached to the outer surface of this structure. These particles were obtained by the deposition and solidification of a nickel complex formed during the electrodeposition process, where myristic acid and nickel ions converge. Specifically, the room temperature was 20°C.

[0065] Example 2:

[0066] Based on Example 1, step S105 changes the deposition time to 5 minutes, while keeping other steps unchanged, to obtain... Figure 4 (c) and Figure 4 (d) shows the surface microstructure.

[0067] Example 3:

[0068] Based on Example 1, step S105 changes the deposition time to 10 min, while keeping other steps unchanged, to obtain... Figure 4 (e) and Figure 4 The surface microstructure shown in (f).

[0069] Example 4:

[0070] Based on Example 1, step S105 changes the deposition time to 15 min, while keeping other steps unchanged, to obtain... Figure 4 (g) and Figure 4 The surface microstructure shown in (h).

[0071] Example 5:

[0072] Based on Example 1, step S105 changes the deposition time to 20 min, while keeping other steps unchanged, to obtain... Figure 4 (i) and Figure 4 The surface microstructure shown in (j).

[0073] like Figure 5 As shown, the TC4 titanium alloy substrates prepared in Examples 2, 3, 4 and 5 were subjected to static contact angle tests; among them, the TC4 titanium alloy material prepared in Example 4 has excellent superhydrophobicity, with a static contact angle of 154.5°±1.5° and a roll-off angle of 2.5°±0.5°.

[0074] Figure 5The results show that when the electrodeposition time was set to 1 minute, the measured surface water contact angle (WCA) was 146 ± 0.5°, and no significant roll-off angle phenomenon was observed. However, when the electrodeposition time was extended to 5 minutes, the WCA increased to 146.5 ± 0.5°, while the roll-off angle (RA) was 16 ± 1.5°. Furthermore, at the 10-minute electrodeposition time, the WCA continued to increase to 150.5 ± 1.5°, while the roll-off angle decreased significantly to 6 ± 0.5°. When the electrodeposition time was increased from 10 minutes to 15 minutes, the WCA reached its maximum value of 154.5 ± 1.5°, and the roll-off angle further decreased to 2.5 ± 0.5°. This result, in contrast to the wetting properties of the thoroughly polished TC4 material (WCA of 35°), strongly demonstrates the effectiveness of the prepared method in constructing superhydrophobic surfaces. When the electrodeposition time reached 20 minutes, the hydrophobic properties of the surface decreased slightly, the WCA dropped to 152.5±1.5°, and the roll-off angle increased to 4±0.5°.

[0075] Based on the above observations, the following conclusions can be drawn: there exists an optimal deposition time window for preparing superhydrophobic coatings via electrodeposition. Beyond this optimal time, the hydrophobic properties of the material gradually stabilize, and may even decrease to some extent. This phenomenon can be mainly attributed to the increased density of the microstructure formed during electrodeposition and the reduced amount of encapsulated air as the electrodeposition time increases, thus affecting the surface's hydrophobic properties.

[0076] The surface elemental analysis results of the TC4 titanium alloy substrate prepared in Example 4 are shown in the figure. Figure 6 As can be seen, the surface microstructure of the TC4 titanium alloy substrate is mainly composed of Ni, C and O, which proves that nickel myristate has been formed. Figure 6 X-ray photoelectron spectroscopy (XPS) was performed on the TC4 titanium alloy substrate (electrodeposition time 15 minutes) to analyze its hydrophobicity after electrodeposition. Figure 6 The XPS full spectrum shows C 1s, O 1s, and Ni 2p peaks on the surface. Carbon is the most abundant element, with an atomic concentration of 79.46%, followed by oxygen (17.54%) and nickel (3.01%). The atomic ratio of carbon, oxygen, and nickel is approximately 27:5:1, which is similar to that of nickel myristate (Ni·[CH3(CH2)]). 12 The composition of COO2 is very consistent. The high oxygen content is likely due to the thermal effect of previous laser processing, which may have triggered physical and chemical metallurgical reactions, resulting in the formation of titanium dioxide on the TC4 titanium alloy substrate. The low surface energy groups (-CH3 and -CH2) in the nickel myristate generated by the reaction can enhance the surface hydrophobicity. Figure 6In (b), the hyperspectral image of C 1s shows two distinct characteristic peaks at 285.0 eV and 288.8 eV, corresponding to the CC(H) bond and the CO=O bond, respectively. These results indicate that the long-chain molecules of myristic acid have been effectively adsorbed onto the nickel film. Furthermore, the weaker peaks detected at 286.5 eV and 287.4 eV are attributed to the CO and C=O bonds, which may be due to the ethanol solution used in the electrodeposition process and residual acetone used for surface cleaning. According to relevant literature, chemisorbed organic compounds from the atmosphere and residual oil in the XPS vacuum chamber may also contribute to the increased content of these chemical bonds. Figure 6 As shown in (c), the hyperspectral image of O 1s shows two distinct peaks at 531.1 eV and 533.2 eV, corresponding to Ni-O and O=CO bonds, respectively. This indicates the presence of nickel oxide and residual oxides on the sample surface, albeit in small amounts. The Ni-OH peak observed at 532 eV suggests that hydroxylation may have occurred on the surface, likely a result of the interaction between nickel and hydroxyl ions during electrodeposition. The main sources of hydroxyl ions can be attributed to two different mechanisms: the first is due to ionization, where water in nickel chloride hexahydrate (NiCl2·6H2O) crystallizes; the second is that after electrodeposition, the TC4 titanium alloy substrate is rinsed with distilled water and then exposed to a humid environment, where hydroxylation occurs on the surface of the TC4 titanium alloy substrate. Figure 6 As shown in (d), the hyperspectral image of Ni 2p exhibits shake-up satellite peaks at 855.9 eV and 873.6 eV, corresponding to the Ni 2p3 / 2 and Ni 2p1 / 2 energy levels, respectively. Furthermore, the peaks at 861.5 eV and 880.4 eV are companion peaks of Ni 2p, indicating that nickel exists in the reaction product in a +2 oxidation state. XPS analysis shows that nickel myristate with low surface energy groups has been successfully deposited on the surface of the TC4 titanium alloy substrate. This suggests that the formed film is a nickel complex bound to an organic acid. All analytical results demonstrate that the low surface energy compound has been successfully deposited on the TC4 titanium alloy substrate, thereby enhancing its superhydrophobic properties.

[0077] like Figure 7 , Figure 8As shown, anti-icing tests were conducted on raw, unprocessed TC4 titanium alloy materials, laser-processed TC4 titanium alloy materials, TC4 titanium alloy materials obtained in Example 1, Example 2, Example 3, Example 4, and Example 5. The test method was as follows: The test was conducted at an ambient temperature of 20°C, a relative humidity of 65%, and a cold wall surface temperature of -10°C. 10 μL of deionized water was dropped onto the surface of the TC4 titanium alloy material using a syringe, and the freezing process was observed and recorded. Frosting experiments were conducted at an ambient temperature of 15°C, a relative humidity of 60%, and a cold wall surface temperature of -10°C. Each frosting cycle lasted 30 minutes, and the mass change of the TC4 titanium alloy material was quantified using an electronic balance. For the untreated TC4 titanium alloy material, ice formation began at the bottom of the water droplet within 7 seconds, and the ice completely solidified by 30 seconds. For TC4 titanium alloy material treated only by laser, icing begins at 15 seconds and completes freezing at 36 seconds. The TC4 titanium alloy material prepared by this invention requires the longest freezing time; water droplets begin to freeze at 590 seconds and completely solidify at 633 seconds, a freezing time 21 times longer than that of untreated TC4 titanium alloy material. Furthermore, when the deposition time exceeds the optimal window period, the anti-icing performance may decrease; the nanostructure produced by prolonged electrodeposition may become too dense, potentially hindering surface anti-icing properties. In addition, under the same conditions, the freezing time of droplets is inversely proportional to the mass of frost formed; surfaces that delay droplet freezing tend to accumulate less frost.

[0078] Figure 7To illustrate the freezing process of water droplets on different TC4 titanium alloy surfaces at -10°C, the formation of a convex peak during freezing was used as the indicator of complete freezing. The anti-icing performance of untreated TC4 titanium alloy, laser-processed TC4 titanium alloy, and TC4 titanium alloy prepared with different deposition times was compared. For the untreated TC4 titanium alloy surface, ice formation began at the bottom of the droplet within 7 seconds, and the droplet completely solidified, forming a convex peak, by 30 seconds. This indicates that the untreated TC4 titanium alloy surface has relatively poor anti-icing performance and a short freezing time. For the laser-processed TC4 titanium alloy surface, ice formation began at 15 seconds and was completely frozen at 36 seconds. Compared to the untreated TC4 titanium alloy surface, laser processing slightly prolonged the freezing time, but the improvement in anti-icing performance remained limited. After 1 minute of electrodeposition, ice formation on the TC4 titanium alloy surface began at 7 seconds and was completely formed at 48 seconds, showing superior anti-icing performance compared to laser treatment. TC4 titanium alloy material electrodeposited for 5 minutes began to freeze at 42 seconds and was completely solidified at 73 seconds, with the freezing time further extended. When the electrodeposition time of TC4 titanium alloy material was extended to 10 minutes, the freezing time was significantly prolonged, with the freezing process starting at 307 seconds and completely freezing at 364 seconds, resulting in a substantial improvement in anti-icing performance. After 15 minutes of electrodeposition, the TC4 titanium alloy material exhibited the longest freezing time, with water droplets becoming opaque and beginning to freeze at 590 seconds and completely freezing at 633 seconds, demonstrating a significant enhancement in anti-icing performance. For TC4 titanium alloy material electrodeposited for 20 minutes, water droplets were observed to begin freezing at 533 seconds and completely freezing at 570 seconds. These results indicate that when the deposition time exceeds the optimal duration, the anti-icing performance decreases, and the nanostructure produced by long-term electrodeposition becomes too dense, which is detrimental to the surface's anti-icing properties.

[0079] Figure 8 The results showed that after 1 minute of electrodeposition, the average mass of frost formed on TC4 titanium alloy was 0.0675 grams. When the deposition time was extended to 5 minutes, the frost mass decreased to 0.0590 grams. After 10 minutes of electrodeposition, the frost mass further decreased to 0.0575 grams, indicating that the surface microstructure effectively delayed ice crystal growth. After 15 minutes of electrodeposition, the frost mass was 0.0524 grams. After 20 minutes of electrodeposition, the frost mass increased slightly to 0.0532 grams, indicating that the surface's anti-frost ability had reached a saturation point, and further extending the deposition time did not improve the anti-icing performance. A comparison of the freezing and frost test results showed that, under the same conditions, the freezing time of droplets was inversely proportional to the mass of frost formed. Surfaces that delayed droplet freezing tended to accumulate less frost, demonstrating a good correlation between the two types of experiments.

[0080] like Figure 9As shown, cyclic wear tests were conducted on TC4 titanium alloy materials obtained through laser processing only, as well as those obtained in Example 1, Example 2, Example 3, Example 4, and Example 5. The surface of the TC4 titanium alloy materials was subjected to abrasion testing using 1000-grit silicon carbide sandpaper. During the test, a 200g weight was placed and fixed on the TC4 titanium alloy material, and then dragged 10 cm horizontally and 10 cm vertically, thus constituting one cycle. At the end of each of the five cycles, the wettability of the TC4 titanium alloy material was evaluated using a contact angle tester. After 50 wear cycles, the droplet contact angles of the TC4 titanium alloy materials obtained in Example 2, Example 3, Example 4, and Example 5 remained above 135°. Figure 10 As shown, the three-dimensional morphology of the TC4 titanium alloy material obtained in Example 4 is visible before and after 50 wear cycles. The armored structure only shows local damage, and the nanoscale surface deposition layer is still clearly discernible. This indicates that the armored structure constructed by the laser microtexturing technology used in this invention has a certain degree of wear resistance. It can effectively inhibit the large-area peeling of micro / nano structures caused by friction, delay the sharp drop in surface roughness, and provide protection for the hydrophobic groups inside the structure.

[0081] Figure 9 The study indicates that the surface wettability of TC4 titanium alloy deteriorates with increasing cycle count, and some electrodeposited layers peel off, leading to a decrease in hydrophobicity. For TC4 titanium alloy with a 1-minute electrodeposition time, the WCA (Weighted Aperture Coefficient) dropped below 135° after the 20th rubbing cycle and further decreased to 125° after the 50th cycle. This hydrophobicity level is comparable to that of TC4 titanium alloy treated only by laser, suggesting that its wear resistance and hydrophobicity are significantly lower than surfaces with other deposition times. This phenomenon is attributed to the fact that the short-term nickel film deposited in 1 minute does not bond well with the substrate, and the electric field lines concentrate at the electrode edges due to the edge effect. Nickel ions preferentially reduce and deposit at the edges or outer surfaces, forming uneven, unstable micro / nano structures that are more easily damaged under wear, thus weakening the surface's ability to maintain hydrophobicity.

[0082] The TC4 titanium alloy material obtained in Example 4 was subjected to a tape peeling test. The adhesion strength between the electrodeposited coating and the substrate is an important indicator for measuring its mechanical stability. Figure 11 (a) illustrates the operation of this method. In the experiment, a cross-hatching tool was first used to cut a 2 mm spacing cross-hatching pattern onto the coating surface. Then, tape was applied to the surface and peeled off. This process was repeated several times, and the scratches and peeling marks on the coating surface were compared before and after testing. The surface condition of the TC4 titanium alloy material after 50 tape peels is shown below. Figure 11 As shown in (b), after 50 tape peeling cycles, no obvious peeling marks appeared on the surface of the composite coating of the TC4 titanium alloy material. According to GB / T9286 standard, this indicates that... Figure 11 (c) The adhesion grade of the surface coating on the TC4 titanium alloy material reaches level 1, demonstrating excellent bonding performance. During 50 tape peel tests, the contact angle of the coating consistently remained above 150°, indicating that the surface coating of the TC4 titanium alloy material possesses high stability, and the surface wettability changes as follows: Figure 11 As shown in (d), the superhydrophobic properties of the TC4 titanium alloy surface remain essentially unchanged. This stability is attributed to the synergistic effect of laser processing and electrodeposition. The combination of these two methods enhances the coating's peel resistance. The armored structure constructed by the laser on the substrate surface increases the contact area between the coating and the substrate and forms a mechanical interlocking structure, thereby increasing the adhesion strength between the nickel layer and the substrate due to the anchoring effect.

[0083] Figure 10 The image shows the three-dimensional morphology of the TC4 titanium alloy surface. It can be observed that the electrodeposition process is not limited by the original complex morphology; the deposited layer uniformly covers the surface and improves the surface roughness, thus achieving superhydrophobic properties. The right image shows the surface morphology of the TC4 titanium alloy after 50 wear cycles. It can be observed that the surface height is significantly reduced after wear, and the microstructure morphology remains more complete. There is virtually no exposure of the TC4 titanium alloy substrate. This phenomenon suggests that the electrodeposited layer has embedded itself in the armor gaps, forming a mechanical interlock with the surface microstructure, resulting in high bonding strength and effectively resisting detachment caused by sandpaper friction.

[0084] In the preparation of the superhydrophobic armored TC4 titanium alloy material of this invention, the variation in electrodeposition time affects the overall properties of the final surface. The results show that the superhydrophobic armored TC4 titanium alloy material with an electrodeposition time of 15 minutes exhibits the best overall performance.

[0085] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method for preparing a superhydrophobic armored TC4 titanium alloy material, characterized in that, Includes the following steps: The surface of the TC4 titanium alloy substrate is pretreated; The surface of the TC4 titanium alloy substrate is armored; The TC4 titanium alloy substrate is subjected to electrodeposition pretreatment again to prepare a deposition layer on the surface of the TC4 titanium alloy substrate; The surface of the TC4 titanium alloy substrate is dried to obtain a superhydrophobic armored TC4 titanium alloy material.

2. The method for preparing the superhydrophobic armored TC4 titanium alloy material according to claim 1, characterized in that, The surface of the TC4 titanium alloy substrate is armored, specifically including: The surface of the TC4 titanium alloy substrate is laser-processed to form a grid pattern on the surface of the TC4 titanium alloy substrate.

3. The method for preparing the superhydrophobic armored TC4 titanium alloy material according to claim 2, characterized in that, The surface of the TC4 titanium alloy substrate was laser-processed using a nanosecond pulsed laser with a wavelength of 1064 nanometers.

4. The method for preparing the superhydrophobic armored TC4 titanium alloy material according to claim 3, characterized in that, The laser processing has a scanning speed of 300 mm / s, a scanning frequency of 50 kHz, a pulse width of 1 μs, a power of 8 W, a processing number of 10 times, and a laser spacing of 72 μm.

5. The method for preparing the superhydrophobic armored TC4 titanium alloy material according to any one of claims 1 to 4, characterized in that, The TC4 titanium alloy substrate is subjected to a second electrodeposition pretreatment to prepare a deposition layer on the surface of the TC4 titanium alloy substrate, specifically including: Electrodeposition was performed in an electrodeposition solution using the TC4 titanium alloy substrate as the cathode and a pure nickel sheet as the anode. After electrodeposition, nickel complex deposited particles adhere to the surface of the TC4 titanium alloy substrate.

6. The method for preparing the superhydrophobic armored TC4 titanium alloy material according to claim 5, characterized in that, During the electrodeposition process, the cathode current density was 3.5 A / dm², the electrodeposition solution temperature was 70°C, and the process lasted for 15 minutes.

7. The method for preparing the superhydrophobic armored TC4 titanium alloy material according to claim 6, characterized in that, The electrodeposition solution is: Add NiCl2·6H2O and myristic acid to anhydrous ethanol and mechanically stir for 30 minutes at a constant temperature.

8. The method for preparing the superhydrophobic armored TC4 titanium alloy material according to claim 7, characterized in that, The concentration of NiCl2·6H2O is 22 g / L, the concentration of myristic acid is 25 g / L, and the constant temperature is 70℃. The mechanical stirring uses a magnetic rotor and is performed at a speed of 60 r / min.

9. The method for preparing the superhydrophobic armored TC4 titanium alloy material according to any one of claims 1 to 4, characterized in that, The TC4 titanium alloy substrate is subjected to a second electrodeposition pretreatment to prepare a deposition layer on the surface of the TC4 titanium alloy substrate, which further includes: The electrodeposition pretreatment is as follows: The TC4 titanium alloy substrate was immersed in a 10 wt.% HCl solution for forty seconds, then ultrasonically cleaned with deionized water for ten minutes, and finally dried with nitrogen.

10. The method for preparing the superhydrophobic armored TC4 titanium alloy material according to any one of claims 1 to 4, characterized in that, The surface of the TC4 titanium alloy substrate is dried to obtain a superhydrophobic armored TC4 titanium alloy material, specifically including: The TC4 titanium alloy substrate was dried at 60°C for twelve hours and then cooled to room temperature.

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