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Article

Efficient and Controllable Preparation of Super-Hydrophobic Alumina-Based Ceramics Coating on Aviation Al-Li Alloy Surface for Corrosion Resistance and Anti-Icing Behavior

by
Ben Li
1 and
Xuewu Li
2,*
1
Engineering Research Center of Additive Manufacturing Aeronautical Materials of Henan Province, Nanyang Institute of Technology, Nanyang 473004, China
2
School of Mechanical Engineering, Xi’an University of Science and Technology, 58 Yanta Road, Xi’an 710054, China
*
Author to whom correspondence should be addressed.
Coatings 2024, 14(9), 1223; https://doi.org/10.3390/coatings14091223
Submission received: 3 September 2024 / Revised: 16 September 2024 / Accepted: 19 September 2024 / Published: 22 September 2024
(This article belongs to the Special Issue Research Progress and Application of Super-hydrophobic Anti-icing Surface)
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Abstract

:
Al-Li alloys have been widely applied in aircraft structural component and shell material. However, Al-Li alloys are prone to corrosion failure, which leads to a considerable safety risk in the aerospace field and greatly limits their industrial application. Herein, a simple, low-cost, and large-scale air-spraying technique is developed for the preparation of an alumina-based ceramics coating with enhanced corrosion resistance and anti-icing behavior. The results show that the static contact angle of the as-prepared coating is 157.2 ± 0.4°, and the rolling angle is only 9.8°, suggesting a super-hydrophobic surface. Meanwhile, the electrochemical corrosion potential of the coating is 70 mV higher than that of the substrate, and the corrosion current density of the coating also decreases by 1 order of magnitude, indicating a significantly improved corrosion resistance. In addition, the fabricated super-hydrophobic coating also shows excellent anti-pollution and anti-icing characteristics. This work provides positive guidance for expanding the application of hydrophobic coating in the aerospace industry, especially in some complex corrosion, icing, and pollution environments.

1. Introduction

The 2198 Al-Li alloy plays a very important role in human daily life and various processing industries [1,2]. Meanwhile, Al-Li alloys have excellent mechanical properties and lightweight characteristics, which is why they are often used in aircraft structural component and shell material [3,4]. However, Li is a very reactive element, so Al-Li alloys are highly susceptible to corrosion in wet environments [5,6], thus resulting in a significant safety hazard in the aerospace field. Accordingly, it is very important to explore the corrosion resistance of Al-Li alloys.
Various methods can be adopted to improve the corrosion resistance of Al-Li alloys, such as the electrochemical protection method [7], corrosion inhibitor introduction [8], and surface coating technology [9,10]. The electrochemical protection method utilizes metal materials with highly active chemical properties, such as Mg, Al, and Zn, to serve as sacrificial anode materials [11,12]. These materials form an electrochemical circuit with the metal materials of the protected cathode. Under the action of an external current, the potential of the metal material is positively shifted to restrict the material corrosion [13,14]. However, during the consumption process of the anode metal material, massive metal ions are released, directly causing an environmental pollution issue [15]. In addition, the cost of the electrochemical protection method is also high [16], which further limits its application to a certain extent.
The corrosion inhibitor is a chemical substance or mixture with an appropriate concentration and form that can prevent or slow down metal material corrosion [17]. The rational use of a corrosion inhibitor is an effective method to prevent corrosion. However, the corrosion inhibitor itself is corrosive, which means that special attention to safety issues is required [18]. Meanwhile, in industrial production, if the corrosion inhibitor is not used properly, it may cause environmental and ecological pollution [19]. In addition, most of the corrosion inhibitors are relatively expensive, and some highly effective corrosion inhibitors may have significant toxicity [20]. In summary, although the corrosion inhibitor has a significant effect on corrosion resistance, it still requires great attention to safety, environmental impact, and cost issues.
Currently, inspired by the lotus leaf effect [21,22], super-hydrophobic coating provides an effective way to solve the corrosion problem of Al-Li alloys due to its excellent liquid repellence [23]. Meanwhile, the super-hydrophobic coating also has excellent self-cleaning, anti-pollution, and anti-icing behaviors [24,25]. For the bionic super-hydrophobic coating, it is very important to select appropriate preparation methods. Currently, the common coating preparation methods include solution impregnation, sol-gel, physical vapor deposition, etc. [26,27,28]. Solution impregnation involves adding a designed solution onto the sample surface and then forming a coating after further baking or heat treatment [29]. In the sol-gel process, the gel is coated on the substrate surface, and then further solvent evaporation or heat treatment is carried out [30]. Physical vapor deposition is a method of depositing a gaseous thin film on a substrate surface under high-temperature and high-vacuum conditions [31]. The coating preparation methods mentioned above have some issues in terms of process complexity, cost effectiveness, and stability.
In this work, a simple, low-cost, and large-scale air-spraying technology is developed, and a ceramic-based composite coating is prepared on an Al-Li alloy. The ceramic-based coating generally has good mechanical properties [32]. Meanwhile, the effects of ceramic particle contents on coating wettability, microstructure, and morphology are investigated systematically. Furthermore, the corrosion resistance of the coating is tested. Finally, the anti-pollution and anti-icing characteristics are also discussed in detail.

2. Material and Methods

2.1. Materials

The main materials used in this work are a 2198 Al-Li alloy (Hunan Zhongchuang Aerospace New Material Co., Ltd., Changsha, China), n-hexane (Nanjing Chengzhi Clean Energy Co., Ltd., Nanjing, China), polydimethylsiloxane (PDMS, Bluestar New Material Wuxi Resin Factory, Wuxi, China), nano-alumina particles (Hunan Zhongchuang Aerospace New Material Co., Ltd., Changsha, China), rubber curing agent, anhydrous ethanol, sodium chloride, deionized water, and standard sand (All the above five materials are provided by Wuhan Yingdeli Technology Co., Ltd., Wuhan, China). The specific types of the above materials are shown in Table 1.

2.2. Preparation

Firstly, the 2198 Al-Li alloy was cleaned and polished in anhydrous ethanol and deionized water to remove oil and impurities by using a KQ5200DV ultrasonic cleaner (Kunshan Ultrasonic Instrument Co., Ltd., Kunshan, China). Secondly, a fixed mixture of PDMS and n-hexane was prepared at a mass ratio of 1:10. Meanwhile, nano-alumina particles with different mass ratios were also added. During this process, an SN-MS-3D magnetic stirrer (Shanghai Sile Instrument Co., Ltd., Shanghai, China) was used for magnetic stirring for 1 h to obtain a colorless and transparent solution. In addition, 0.1 g of the silicone rubber curing agent was added and stirred for another 15 min to obtain a homogeneous milky white suspension. Thirdly, the suspension was transferred to the hopper of a W-71 spray gun (Shenzhen Weier Sai Machinery Equipment Co., Ltd., Shenzhen, China) and sprayed onto the Al-Li alloy surface. During the spraying process, the air pressure for spraying was set to 0.7 MPa, the spraying distance was set to 30 cm, and the spraying volume was set to 0.3 mL/cm2. Finally, the sample was subjected to high-temperature drying and curing treatment at 100 °C for 1 h. The above procedure was repeated 5 times to minimize randomness in the experimental process.

2.3. Technical Method Characterization

Using the Contact Angle Measuring Instrument (OCA25, DATAPHYSICS, Stuttgart, Germany), the wettability is evaluated by testing the static water contact angle and rolling angle. When the liquid reaches an equilibrium state on the solid surface, the angle between the gas–liquid boundary and liquid–solid boundary is called the static water contact angle. The rolling angle refers to the angle formed between the inclined surface and horizontal plane when a droplet just rolls on a slowly inclined sample surface.
To investigate the effect of nano-alumina particle amount on the coating surface morphology, a scanning electron microscope (SEM, NOVA Nano SEM 450, FEI, Hillsboro, OH, USA) is used to observe the micro-morphologies of the sprayed coating. An energy-dispersive spectrometer (EDS, X-MAXN50, Oxford Instruments, Abingdon, Oxfordshire, UK) is used to characterize the composition of the as-prepared coating. An energy-dispersive spectrometer (XPS, ESCALAB-250Xi, Thermo Scientific, Waltham, MA, USA) is used to characterize the chemical composition and structure of the as-prepared coating.
An electrochemical workstation (CS2350H, CORRTEST, Shanghai, China) is used to measure the electrochemical impedance and polarization curve of the coating to evaluate its corrosion resistance. The electrochemical impedance spectroscopy (EIS) test is performed with a sinusoidal perturbation amplitude of 10 mV in 10−2–105 Hz. The polarization curve is obtained with a scanning rate of 0.2 mV/s. The anti-icing performance test is conducted by placing the sample in a refrigerator (BCD-483WSPZM, Midea, Foshan, China) to observe the freezing process of the droplet on it.

3. Results and Discussion

3.1. Wettability of Sprayed Coatings

As a kind of metal material with excellent comprehensive properties, the static water contact angle of the 2198 Al-Li alloy is 82.7 ± 1.7°, as shown in Figure 1a. Because the contact angle is less than 90°, the bare Al-Li alloy has obvious hydrophilicity, which can also be seen from the optical diagram in Figure 1b. When the water drops on the bare sample, it spreads out quickly. Under this condition, the droplet on the surface shows an obvious Wenzel wetting model, and it also exhibits a high-viscosity solid–liquid contact interface.
PDMS is a kind of hydrophobic polymer material. In the experiment, nano-alumina particles are used as the filler aggregates of coating material. For the composition of the coating material, the contents of PDMS, silicone rubber, and n-hexane are set to 1 g, 0.1 g, and 10 mL, respectively. And the spraying amount is 0.2 mL/cm2. The wettability of the coating is controlled by changing the mass ratio of PDMS to nano-alumina particles, and the measured results are shown in Figure 2. It can be found that the static contact angle of the coating surface increases from 82.7 ± 1.7° to 103.6 ± 0.3° when the nano-alumina particle mass is 0, indicating that the hydrophobicity is increased slightly. When the mass ratios of PDMS to nano-alumina particles are 1:0.25, 1:0.5, and 1:0.75, the static contact angles increase to 110.8 ± 0.2°, 116.2 ± 0.7°, and 125.3 ± 1.1°, respectively. All the coatings exhibit significant hydrophobic characteristics. And when the mass ratios rise to 1:1, 1:1.25, and 1:1.5, the contact angles increase to 150.4 ± 1.3°, 157.2 ± 0.4°, and 153.8 ± 0.7°, respectively. Meanwhile, when the mass ratio is 1:1.25, the rolling angle of the droplet on the sample surface is as low as 9.8°, which shows obvious super-hydrophobicity. Therefore, 1:1.25 is the optimal mass ratio of PDMS to nano-alumina particles for the sprayed coating.
As mentioned above, the as-prepared coating (1:1.25) exhibits excellent super-hydrophobicity. Figure 3 shows the corresponding contact state between the droplet and the coating. It can be found that when the water drops on the coating surface, the droplet does not spread but remains an approximate spherical shape with excellent water repellency. Under this condition, the droplet exhibits an obvious Cassie wetting model. The high-viscosity solid–liquid contact interface disappears, and the solid–gas–liquid composite contact interface emerges in the Cassie model, thus cutting down the direct contact between the coating and liquid. This greatly reduces the viscous resistance of the sample to liquid, thus exhibiting excellent super-hydrophobic performance.

3.2. Morphologies of Sprayed Coatings

The surface morphology has an important effect on the properties of the sprayed coatings. In the preparation process of super-hydrophobic coating, the adjustment and control of surface roughness are very important. High or low surface roughness can affect the coating wettability. In general, rough coating has a superior hydrophobic effect. This is because the rough surface can increase the static contact angle and reduce the rolling angle, thus improving the hydrophobic performance. However, high surface roughness can also result in a decrease in the stability and durability of the coating. To investigate the effect of nano-alumina particle amount on the coating surface morphology, a scanning electron microscope is used to observe the micro-morphology of the sprayed coating, and the results are shown in Figure 4.
As seen from Figure 4 and the corresponding magnified micro-morphologies of sprayed coatings (Figure 5), many micro-particles are distributed on the surfaces. Meanwhile, with the growth of nano-alumina particle content, the coating surface roughness also increases gradually. Such uneven rough structures have a positive effect on the improvement of the coating hydrophobicity and contribute to the formation of the Cassie wettability model of the contact interface. When the mass ratio of PDMS to nano-alumina particles increases to 1:1.25, the coating surface roughness increases significantly, and the super-hydrophobic performance is obtained. In this state, the rough structure captures a massive air phase, and therefore the high-viscosity solid–liquid contact interface disappears. Instead, the solid–gas–liquid composite contact interface is formed, thereby reducing the direct contact between the coating and liquid. This greatly reduces the viscous resistance of the sample to liquid, thus showing excellent super-hydrophobicity.
The EDS energy spectrum result of the super-hydrophobic coating surface corresponding to a mass ratio of 1:1.25 between PDMS and nano-alumina is shown in Figure 6. The corresponding atomic percentage is shown in Table 2. As seen, the element contents of the coating surface are mainly composed of C, O, Al, Si, and N. However, such element contents vary greatly. Meanwhile, the contents of O and Al elements are the highest, which come from the nano-alumina particles added during the coating preparation process. These high-content alumina particles serve as filling aggregates, thus greatly enhancing the coating surface roughness. Furthermore, the gaps in rough structures store a large amount of air, thereby increasing the contact area between the solid phase and gas phase for improved hydrophobicity.
Figure 7 shows the mapping scanning results of the super-hydrophobic coating surface corresponding to a mass ratio of 1:1.25 between PDMS and nano-alumina. It can be found that the distribution of each element is relatively uniform, but the corresponding structural characteristics are different. It is precisely because of such hierarchical structural features that the super-hydrophobic performance of the coating is achieved. In addition, the carbon content is also relatively high, indicating that the abundant -CH2- and -CH3 nonpolar functional groups are successfully constructed. Then, it greatly reduces the surface free energy of nano-alumina, and the coating is more likely to reach a super-hydrophobic state.
The XPS full spectrum and the corresponding fitted partial spectra of the super-hydrophobic coating surface corresponding to a mass ratio of 1:1.25 between PDMS and nano-alumina are displayed in Figure 8. The diffraction peaks of Si2p, Al2p, C1s, and O1s are clearly seen in the XPS full spectrum. The bimodal binding energy of Al2p is very close to that of the pure alumina. C1s consists of two sub-peaks of 285.0 eV and 283.9 eV, which correspond to the C-H bond and C-Al bond of the polydimethylsiloxane, respectively. O1s consists of two sub-peaks of 532.3 eV and 531.5 eV, which correspond to the Al-O bond in alumina and the Si-O bond in polydimethylsiloxane, respectively. The results demonstrate that because of the introduction of polydimethylsiloxane and alumina, the C-C and C-H groups in the super-hydrophobic coating increase obviously. The non-polar functional groups endow the sprayed coating with ultra-low surface energy, thereby resulting in excellent liquid repellency for the substrate.

3.3. Multiple Functionalities of Sprayed Coatings

Firstly, the anti-pollution behaviors are tested for the bare Al-Li alloy and the coating sample. In the experiment, fruit juice, cola, and milk are used as the pollutants. After the Al-Li alloy is taken out from the juice, cola, and milk, obvious residual pollutants adhere to the alloy surface, indicating that the alloy is easily contaminated. The contrastive anti-pollution test is also conducted for the sample with super-hydrophobic coating corresponding to a mass ratio of 1:1.25 between nano-alumina and PDMS. When the sample is taken out from pollutants, the liquid does not adhere to the coating surface. It can be concluded that the super-hydrophobic coating has outstanding self-cleaning ability. This is because the prepared coating can capture a massive air phase, thus forming a solid–gas–liquid composite contact interface. This greatly reduces the direct contact between the coating and liquid, thus reducing the viscous resistance of the coating to liquid, ultimately exhibiting excellent anti-pollution characteristics.
The rate of metal corrosion is affected by many factors, including the properties of the corrosion medium, temperature, humidity, surface morphology, and chemical composition of metal. In the aviation field, metal components are easy to be corroded by oxidation, moisture, and chemical substances, which seriously affect aircraft safety and service life. Therefore, it is very important to improve the corrosion resistance of the Al-Li alloy, and the super-hydrophobic coating prepared in this work can solve this problem. Figure 9 shows the EIS results of the bare Al-Li alloy and the sample with super-hydrophobic coating. The corrosion resistance of the super-hydrophobic coating is much greater than that of the bare sample. This is because the arc radius of the super-hydrophobic coating is relatively large, which means that the charge transfer resistance of the coating is larger than that of the substrate, thus obtaining stronger corrosion resistance.
The electrochemical Bode diagrams of the bare alloy and the super-hydrophobic sample are also characterized, and the corresponding results are shown in Figure 10. In general, the corrosion of the Al-Li alloy occurs in the low-frequency region of the impedance spectrum. As shown in Figure 10a, the super-hydrophobic coating has a larger impedance modulus value at the low frequency, which means it has stronger corrosion resistance. It can also be found that the impedance modulus of the super-hydrophobic coating increases by about two orders of magnitude compared with the bare alloy. Figure 10b shows the phase curve of the impedance diagram, and it can also be used to determine the current distribution on the electrode surface. In addition, the phase angles of the bare alloy and the super-hydrophobic coating are greater than 45°; thus, it can be considered that the current distributions on both samples are uniform during the whole test process.
Figure 11 shows the potentiodynamic polarization curves of the bare Al-Li alloy and the sample with super-hydrophobic coating. The parameters of the polarization curve include corrosion potential (Ecorr) and corrosion current density (Icorr). If the sample has a relatively large corrosion potential, it means that the corrosion resistance is better. The corrosion current density represents the magnitude of the corrosion rate, and a low corrosion current density means a slow corrosion rate. As seen, the corrosion potential of the super-hydrophobic coating is −0.58 V, which is 70 mV greater than that of the bare Al-Li alloy (−0.65 V). Meanwhile, the corrosion current density of the super-hydrophobic coating is 2.73 × 10−6 A/cm2, which is one order of magnitude lower than that of the bare alloy. The special microstructure and extremely low surface energy of the super-hydrophobic coating can capture a large amount of air. The air cushion together with the excellent hydrophobic isolation effect of such ceramic-based coating provides great corrosion protection for alloy substrates.
The anti-icing performance test is also conducted in this work. The freezing processes of the water droplets on the bare alloy and the as-prepared super-hydrophobic coating sample at −5 °C are recorded in Figure 12. The results show that the water droplet on the super-hydrophobic coating completely freezes at 180 s. However, the water droplet on the bare Al-Li alloy completely freezes at 90 s. It indicates that the super-hydrophobic coating possesses excellent anti-icing behavior, which is due to the different heat transfer coefficients between the two samples. The heat transfer coefficient of the alloy substrate is 83 W/(m·K). The super-hydrophobic coating can capture a large amount of air, so its heat transfer coefficient is much lower than that of the alloy substrate. This will prolong the non-uniform nucleation time at the solid–liquid interface under a low-temperature condition, thus achieving a delayed freezing process.

4. Conclusions

  • The coating prepared by air spraying can capture a large amount of air phase, thus generating a cushion effect to lift the water droplet. Therefore, the high-viscosity solid–liquid contact interface disappears, and a solid–gas–liquid composite contact interface is formed, which reduces the direct contact proportion between the coating and the liquid. This greatly decreases the viscous resistance of the sample to liquid, thereby exhibiting excellent super-hydrophobic performance and anti-pollution characteristics.
  • The corrosion potential of the super-hydrophobic coating is higher than that of the substrate, while the corrosion current density is lower than that of the substrate, which indicates that the corrosion resistance of the sample with super-hydrophobic coating has been significantly improved. On the one hand, the super-hydrophobic coating provides excellent physical isolation against corrosive media. On the other hand, the prepared microstructures can capture air and then enhance the removal effect of corrosive media, thereby further enhancing the corrosion resistance.
  • Compared with the alloy substrate, the droplet freezing time on super-hydrophobic coating is greatly delayed, indicating that the anti-icing behavior is enhanced. This is due to the different heat transfer coefficients between the two samples. The super-hydrophobic coating can capture a large amount of air, so its heat transfer coefficient is much lower than that of the alloy substrate. This will prolong the non-uniform nucleation time at the solid–liquid interface under a low-temperature condition, thus achieving a delayed freezing process.
  • The corrosion resistance of the super-hydrophobic coating prepared in this work was significantly improved compared to the previous structural strategy. For future work, it is necessary to have a deeper simulative understanding of the de-icing mechanism for such super-hydrophobic coating. Meanwhile, it may also be useful to consider the multifunctional coating for thermal and fluid transport applications.

Author Contributions

Conceptualization, X.L. and B.L.; Investigation, X.L.; Resources, B.L.; Data Curation, B.L.; Writing—Original Draft Preparation, B.L. All authors have read and agreed to the published version of the manuscript.

Funding

This work was supported by the China Postdoctoral Science Foundation (2021M691014), the Project of Startup Foundation for Doctoral Research of Nanyang Institute of Technology (NGBJ-2020-02), and the Project Supported by the Youth Science Foundation of Henan Province (No. 232300420327).

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

The data presented in this study are available upon request from the corresponding author.

Conflicts of Interest

The authors declare no conflicts of interest.

References

  1. Zhang, X.Y.; Cui, Z.F.; Pan, X.C.; Chen, Z.; Dong, T.J.; Chen, Y.J. Post-impact Fatigue Performance of 2198-T8 Aluminum-Lithium Alloy Sheet with Pre-crack. J. Test. Eval. 2023, 51, 4328–4339. [Google Scholar] [CrossRef]
  2. Su, W.; Zhu, H.M. In situ corrosion fatigue life of 2198-T8 Al-Li alloy based on tests and DIC technique. Mater. Test. 2022, 64, 1383–1396. [Google Scholar] [CrossRef]
  3. Chen, Y.; Pan, X.; Peng, J.; Wang, F. Effect of coupling damage on fatigue behavior of 2198-T8 aluminum-lithium alloy thin sheet for fuselage. Fatigue Fract. Eng. Mater. Struct. 2022, 45, 754–769. [Google Scholar] [CrossRef]
  4. Pang, Z.; Yang, J.; Cai, Y. Effects of Rotational Speed on the Microstructure and Mechanical Properties of 2198-T8 Al-Li Alloy Processed by Friction Spot Welding. Materials 2023, 16, 1807. [Google Scholar] [CrossRef] [PubMed]
  5. Chen, Y.; Zhang, Y.; Cui, Z.; Wang, F.; Dong, T.; Meng, X. Effect of impact-corrosion coupling damage on fatigue properties of 2198-T8 aluminum-lithium alloy. Eng. Fail. Anal. 2024, 163, 108471. [Google Scholar] [CrossRef]
  6. de Souza Carvalho Machado Machado, C.; Klumpp, R.E.; Ayusso, V.H.; Donatus, U.; Milagre, M.X.; de SAraujo, J.V.; Machado, G.A.F.; Costa, I.S. Effect of surface treatments on the localized corrosion resistance of the AA2198-T8 aluminum lithium alloy welded by FSW process. Surf. Interface Anal. 2019, 51, 1231–1239. [Google Scholar] [CrossRef]
  7. de Sousa Araujo, J.V.; Milagre, M.X.; Klumpp, R.E.; Hugo Ayusso, V.; Donatus, U.; Costa, I. TSA anodising voltage effects on the near-surface coarse intermetallic particles in the AA2024-T3 and AA2198-T8 alloys. Corros. Eng. Sci. Technol. 2022, 57, 380–396. [Google Scholar] [CrossRef]
  8. Sergienko, V.P.; Kozhushko, V.V.; Bukharov, S.N.; Merinov, V.K. Effect of Corrosion Inhibitors in Compositions of Friction Composites on Corrosion Resistance of the Metal Counterbody and Noise Generation during Friction. J. Frict. Wear 2024, 44, 259–265. [Google Scholar] [CrossRef]
  9. Sahoo, B.; Das, T.; Paul, J. Thermal spraying and related technologies for the surface modification of al alloys: Review. Surf. Rev. Lett. 2022, 29, 2230009. [Google Scholar] [CrossRef]
  10. Wondwosen, D.; Jiajun, X.; Pawan, L.T. Review of internal and external surface finishing technologies for additively manufactured metallic alloys components and new frontiers. Prog. Addit. Manuf. 2023, 8, 1433–1453. [Google Scholar]
  11. Gong, S.H.; Lim, H.J.; Lee, J.H.; Yoo, Y.; Yu, S.; Lim, H.D.; Jung, H.W.; Ko, J.S.; Kim, I.S.; Kim, H.S. Electrochemical assessment of highly reversible SnO2-coated Zn metal anodes prepared via atomic layer deposition for aqueous Zn-ion batteries. Appl. Surf. Sci. 2023, 611, 155633. [Google Scholar] [CrossRef]
  12. Xia, D.H.; Deng, C.M.; Macdonald, D.; Jamali, S.; Mills, D.; Luo, J.L.; Strebl, M.G.; Amiri, M.; Jin, W.; Song, S.; et al. Electrochemical measurements used for assessment of corrosion and protection of metallic materials in the field: A critical review. J. Mater. Sci. Technol. 2022, 112, 151–183. [Google Scholar] [CrossRef]
  13. Hino, M.; Hori, T. Phosphate Anodization for Magnesium Alloys and Its Anticorrosion Mechanism. J. Jpn. Soc. Tribol. 2022, 67, 484–489. [Google Scholar]
  14. Group, P. Researchers develop green energy-based electrochemical corrosion protection. Paintindia 2023, 73, 125. [Google Scholar]
  15. Jin, H.; Ji, R.; Sun, H.; Liu, S.; Dong, T.; Wang, L.; Zhao, L.; Ma, C.; Liu, Y.; Cai, B.; et al. Efficient preparation of Ni-Fe-SiC pipeline internal surface coating by active/inert metal combined anode jet electrodeposition. J. Manuf. Process. 2023, 89, 284–297. [Google Scholar] [CrossRef]
  16. Noda, K.; Koseki, W.; Hirobe, S.; Shiratori, H.; Yagi, Y. Fundamentals of Corrosion Reaction and Corrosion Protection by Surface Treatment. J. Jpn. Soc. Tribol. 2022, 67, 458–465. [Google Scholar]
  17. Ouakki, M.; Galai, M.; Cherkaoui, M. Imidazole derivatives as efficient and potential class of corrosion inhibitors for metals and alloys in aqueous electrolytes: A review. J. Mol. Liq. 2022, 345, 117815. [Google Scholar] [CrossRef]
  18. Galleguillos Madrid, F.M.; Soliz, A.; Cáceres, L.; Bergendahl, M.; Leiva-Guajardo, S.; Portillo, C.; Olivares, D.; Toro, N.; Jimenez-Arevalo, V.; Páez, M. Green Corrosion Inhibitors for Metal and Alloys Protection in Contact with Aqueous Saline. Materials 2024, 17, 3996. [Google Scholar] [CrossRef]
  19. Privitera, A.; Ruggiero, L.; Venditti, I. One step nanoencapsulation of corrosion inhibitors for gradual release application. Mater. Today Chem. 2022, 24, 100851. [Google Scholar] [CrossRef]
  20. Auepattana, A.K.; Phakkeeree, T.; Crespy, D. Stimuli-responsive polymeric additives for anticorrosion. J. Appl. Polym. Sci. 2022, 139, 51730. [Google Scholar] [CrossRef]
  21. Golubina, E.N.; Kizim, N.F. From Hydrophylicity to Surface Hydrophobicity: Variation of the Wettability of a Material on a Substrate Due to Local Vibrational Effects during Its Interface Synthesis. Russ. J. Phys. Chem. 2023, 97, 100–104. [Google Scholar] [CrossRef]
  22. Guo, M.; Rong, Y.; Huang, Y.; Feng, X.; Hu, H.; Wu, C.; Zhang, G. Ultrafast laser-chemical modification hybrid fabrication of hydrostatic bearings with a superhydrophobicity solid-liquid interface. Sci. China Technol. Sci. 2024, 67, 696–708. [Google Scholar] [CrossRef]
  23. Li, X.; Ma, C.; Shi, T.; Yang, H.; Zhang, C.; Qi, W.; Li, C.; Liu, R.; He, W.; Liu, Y. Waterborne robust superhydrophobic PFDTES@TiO2-PU coating with stable corrosion resistance, long-term environmental adaptability, and delayed icing functions on Al-Li alloy. J. Mater. Res. Technol. 2024, 32, 3357–3370. [Google Scholar] [CrossRef]
  24. Abu, M.M.; Hyun, K.S.; Kye-Si, K. Multinozzle electrospray method for high-throughput and uniform coating: Application of superhydrophobic coating. J. Coat. Technol. Res. 2023, 20, 1069–1081. [Google Scholar]
  25. Piscitelli, F.; Palazzo, S.; Nicola, F.D. Icing Wind Tunnel Test Campaign on a Nacelle Lip-Skin to Assess the Effect of a Superhydrophobic Coating on Ice Accretion. Appl. Sci. 2023, 13, 5183. [Google Scholar] [CrossRef]
  26. Gallyamova, R.; Safiullin, R.; Dokichev, V.; Musin, F.F. Preparation of TiO2 Coatings on Carbon Fibers. Mater. Sci. Forum 2022, 1049, 117–123. [Google Scholar] [CrossRef]
  27. Lin, W.T.; Lin, Z.W.; Kuo, T.Y.; Chien, C.S.; Huang, J.W.; Chung, Y.L.; Chang, C.P.; Ibrahim, M.Z.; Lee, H.T. Mechanical and biological properties of atmospheric plasma-sprayed carbon nanotube-reinforced tantalum pentoxide composite coatings on Ti6Al4V alloy. Surf. Coat. Technol. 2022, 437, 128356. [Google Scholar] [CrossRef]
  28. Li, J.; Li, T.; Yuwono, J.A.; Meng, G.; Feng, Z. Developing levodopa-modified sol-gel coating with enhanced anticorrosion performance on Mg alloy AZ31. Anti-Corros. Methods Mater. 2023, 70, 129–138. [Google Scholar] [CrossRef]
  29. Camalan, M.; Arol, A.H. Preliminary assessment of spray coating, solution-immersion and dip coating to render minerals superhydrophobic. Miner. Eng. 2022, 176, 107357. [Google Scholar] [CrossRef]
  30. Eren, O.; Kamara, A.M.; Sezer, H.K.; Marimuthu, S. Synthesis of Aluminium Nitride-Based Coatings on Mild Steel Substrates Utilising an Integrated Laser/Sol–Gel Method. Photonics 2024, 11, 382. [Google Scholar] [CrossRef]
  31. Ada, H.; El Rubaye, A.Q.; Tokeser, E.A.; Mavi, A.; Aksoz, S. Coating of Ti6Al4V Alloys by Physical Vapor Deposition Method and Micro-scratch and Corrosion Test Investigations of Coated Samples. J. Adv. Appl. Sci. 2023, 2, 36–45. [Google Scholar] [CrossRef]
  32. Li, X.; Liu, H.; Guo, W.; Zhou, L.; Cui, Q.; Deng, X.; Shu, W.; Shi, T.; Xing, Z.; Wang, H. Effect of TiO2 content on the thermal control properties of Al2O3-xTiO2 composite coatings prepared by supersonic plasma spraying technology. J. Mater. Res. Technol. 2024, 32, 3582–3593. [Google Scholar] [CrossRef]
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Figure 1. (a) The measurement result of the static water contact angle on the 2198 Al-Li alloy surface; (b) the contacting state between the liquid and the 2198 Al-Li alloy.
Figure 1. (a) The measurement result of the static water contact angle on the 2198 Al-Li alloy surface; (b) the contacting state between the liquid and the 2198 Al-Li alloy.
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Figure 2. The wettability results for the sprayed coatings with different mass ratios of PDMS to nano-alumina particles.
Figure 2. The wettability results for the sprayed coatings with different mass ratios of PDMS to nano-alumina particles.
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Figure 3. The contact state between the droplet and the coating corresponding to a mass ratio of 1:1.25 for PDMS and nano-alumina particles.
Figure 3. The contact state between the droplet and the coating corresponding to a mass ratio of 1:1.25 for PDMS and nano-alumina particles.
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Figure 4. The micro-morphologies of the sprayed coatings with different mass ratios of PDMS to nano-alumina particles: (a) 1:0, (b) 1:0.25, (c) 1:0.5, (d) 1:0.75, (e) 1:1, (f) 1:1.25, (g) 1:1.5.
Figure 4. The micro-morphologies of the sprayed coatings with different mass ratios of PDMS to nano-alumina particles: (a) 1:0, (b) 1:0.25, (c) 1:0.5, (d) 1:0.75, (e) 1:1, (f) 1:1.25, (g) 1:1.5.
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Figure 5. The magnified micro-morphologies of the sprayed coatings with different mass ratios of PDMS to nano-alumina particles: (a) 1:0, (b) 1:0.25, (c) 1:0.5, (d) 1:0.75, (e) 1:1, (f) 1:1.25, (g) 1:1.5.
Figure 5. The magnified micro-morphologies of the sprayed coatings with different mass ratios of PDMS to nano-alumina particles: (a) 1:0, (b) 1:0.25, (c) 1:0.5, (d) 1:0.75, (e) 1:1, (f) 1:1.25, (g) 1:1.5.
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Figure 6. The EDS energy spectrum result of the super-hydrophobic coating surface corresponding to a mass ratio of 1:1.25 between PDMS and nano-alumina.
Figure 6. The EDS energy spectrum result of the super-hydrophobic coating surface corresponding to a mass ratio of 1:1.25 between PDMS and nano-alumina.
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Figure 7. The mapping scanning results of the super-hydrophobic coating surface corresponding to a mass ratio of 1:1.25 between PDMS and nano-alumina.
Figure 7. The mapping scanning results of the super-hydrophobic coating surface corresponding to a mass ratio of 1:1.25 between PDMS and nano-alumina.
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Figure 8. The XPS full spectrum (a) and the fitted partial spectra of the super-hydrophobic coating surface corresponding to a mass ratio of 1:1.25 between PDMS and nano-alumina: (b) Al2p, (c) C1s, (d) O1s.
Figure 8. The XPS full spectrum (a) and the fitted partial spectra of the super-hydrophobic coating surface corresponding to a mass ratio of 1:1.25 between PDMS and nano-alumina: (b) Al2p, (c) C1s, (d) O1s.
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Figure 9. The electrochemical impedance spectroscopy of the bare Al-Li alloy and the sample with super-hydrophobic coating.
Figure 9. The electrochemical impedance spectroscopy of the bare Al-Li alloy and the sample with super-hydrophobic coating.
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Figure 10. The electrochemical Bode diagrams of the bare Al-Li alloy and the sample with super-hydrophobic coating: (a) log F–log |Z| image, (b) log F–phase image.
Figure 10. The electrochemical Bode diagrams of the bare Al-Li alloy and the sample with super-hydrophobic coating: (a) log F–log |Z| image, (b) log F–phase image.
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Figure 11. The polarization curves of the bare Al-Li alloy and the sample with super-hydrophobic coating.
Figure 11. The polarization curves of the bare Al-Li alloy and the sample with super-hydrophobic coating.
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Figure 12. The freezing processes of the water droplets on the bare Al-Li alloy and the sample with super-hydrophobic coating at −5 °C.
Figure 12. The freezing processes of the water droplets on the bare Al-Li alloy and the sample with super-hydrophobic coating at −5 °C.
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Table 1. The main materials used in the experimental process.
Table 1. The main materials used in the experimental process.
NamesTypes
2198 Al-Li alloy1 mm thick
nano-alumina particles50 nm, 99.8%
PDMSSylgard184
silicone rubber curing agentSylgard184
n-hexane97.0%
anhydrous ethanol99.7%
sodium chloride99.5%
standard sand0.3–0.6 mm
deionized water99.7%
Table 2. The atomic percentage of the super-hydrophobic coating surface corresponding to a mass ratio of 1:1.25 between PDMS and nano-alumina.
Table 2. The atomic percentage of the super-hydrophobic coating surface corresponding to a mass ratio of 1:1.25 between PDMS and nano-alumina.
ElementsSignal TypeAt %
CEDS24.65
NEDS0.02
OEDS34.76
AlEDS26.78
SiEDS23.79
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MDPI and ACS Style

Li, B.; Li, X. Efficient and Controllable Preparation of Super-Hydrophobic Alumina-Based Ceramics Coating on Aviation Al-Li Alloy Surface for Corrosion Resistance and Anti-Icing Behavior. Coatings 2024, 14, 1223. https://doi.org/10.3390/coatings14091223

AMA Style

Li B, Li X. Efficient and Controllable Preparation of Super-Hydrophobic Alumina-Based Ceramics Coating on Aviation Al-Li Alloy Surface for Corrosion Resistance and Anti-Icing Behavior. Coatings. 2024; 14(9):1223. https://doi.org/10.3390/coatings14091223

Chicago/Turabian Style

Li, Ben, and Xuewu Li. 2024. "Efficient and Controllable Preparation of Super-Hydrophobic Alumina-Based Ceramics Coating on Aviation Al-Li Alloy Surface for Corrosion Resistance and Anti-Icing Behavior" Coatings 14, no. 9: 1223. https://doi.org/10.3390/coatings14091223

APA Style

Li, B., & Li, X. (2024). Efficient and Controllable Preparation of Super-Hydrophobic Alumina-Based Ceramics Coating on Aviation Al-Li Alloy Surface for Corrosion Resistance and Anti-Icing Behavior. Coatings, 14(9), 1223. https://doi.org/10.3390/coatings14091223

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