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Super-hydrophobicity inspired by natural water-repellent surfaces has received tremendous attention for surface functionalization of metallic materials in many applications. Problems of corrosion and/or contamination that happens on the surface can be partially solved as the material obtained super-hydrophobicity. Appropriate surface pattern and low surface energy are the two key factors that can realize super-hydrophobicity. In the present paper, laser surface texturing (LST) followed by decoration of Hexadecyltrimethoxysilane (HDTMS) was conducted to manipulate the super-hydrophobicity and corrosion resistance of AISI 316 stainless steel (SS) on the surface. Scanning electron microscopy (SEM) and an ultra-depth field microscope were employed to characterize the surface morphologies of the received samples before and after corrosion tests. Corrosion resistance and super-hydrophobicity for the related samples were investigated using electrochemical tests and water contact angle measurements. It was found that various surface patterns differed with intervals (250, 150, 80, and $d=50\mu$m,) between two micro-dimples have formed on 316 SS sample surfaces after LST treatment. The surface roughness values gradually increased with the decrease of interval. The 316 SS samples obviously reduced surface energy values after HDTMS decoration. In simulated haze solution, electrochemical tests demonstrated that the 316 SS sample treated with $\mathrm{\text{HDTMS}}+\mathrm{\text{LST}}$ (HT-316 SS, $d=50\mu$m) exhibited lower corrosion and higher corrosion potential current density than the smooth 316 SS (S-316 SS), $\mathrm{\text{HDTMS}}+\mathrm{\text{S}}$-316 SS (HS-316 SS), and LST 316 SS (T-316 SS, $d=50\mu$m) samples. As expected, the HT-316 SS ($d=50\mu$m) exhibited the highest water contact angle of 155.85^∘ as compared to HS-316 SS and other HT-316 SS samples. Meanwhile, the superhydrophobic surface of HT-316 SS ($d=50\mu$m) exhibits super-oleophilic and self-cleaning properties.

Aluminum alloy was subjected to anodization and then treated with a mixture of dodecanoic acid and aluminum sulfate, which produced an aluminum alloy that was extremely hydrophobic. Using energy dispersive spectroscopy (EDS), Fourier transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM), the surface structure and composition of the aluminum alloy samples were examined. The results showed that the dodecanoic acid and aluminum sulfate mixture-treated aluminum alloy surface underwent etching while also absorbing aluminum dodecanoate, resulting in a micro–nano conical nonuniform structure. With a static contact angle (CA) of 156${}^{\circ }$, the superhydrophobic aluminum alloy has exceptional anti-icing and self-cleaning qualities. When compared to anodized aluminum alloys, the superhydrophobic aluminum alloy exhibits improved corrosion resistance in a 3.5wt.% NaCl solution.

Hierarchical alveolate structures in nano- to microscale were fabricated on both aluminum and stainless steel substrates via a chemical etching. On aluminum surfaces, sharp edged caves and plateaus were found. On stainless steel substrate, fine papillae stand on protuberances. These surfaces exhibit super-hydrophobic properties after the fluorination treatment, their water contact angles are 158° and 160°, respectively, with the contact angle hysteresis of about 5°. The roll off angle is about 5°. Ice melting behaviors on a plate of aluminum super-hydrophobic surface were compared with those on a hydrophilic one, their difference shows that the new feature of super-hydrophobic surface could be expected.