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This work presented a facile method to fabricate high‐white and robust superhydrophobic film on Al alloy surface. Ni/Al2O3 film with appropriate roughness and high‐white surface were constructed on the Al alloy by a simple chemical bath method via placing the Al alloy into the Ni2+ aqueous solution. Then the surface energy was reduced by spin‐coating the stearic acid (STA) to achieve excellent superhydrophobicity. As expected, the reflectivity, self‐cleaning, corrosion resistivity and mechanical durability of Al alloy after modification have all displayed dramatic enhancements. The reflectance of the modified Al alloy is far above the pristine Al alloy at all wavelengths (200‐2000 nm). This high‐white film with remarkable reflectivity can effectively reduce its surface temperature and improve visibility in practical application. Finally, a champion water contact angle of 161° and corrosion resistivity of 97.6% were attained by coating Ni/Al2O3‐STA composite film on Al alloy. The Leeb hardness of superhydrophobic film coated Al alloy was enhanced from 325 to 461 after coating superhydrophobic film on Al alloy. This work provides a framework for the development of superhydrophobic Al alloy with high‐whiteness and robustness.This article is protected by copyright. All rights reserved.

The development of aluminum (Al) alloys with superb anticorrosion and self-cleaning properties for prolonging the working life and reducing maintenance cost is a hot topic of concern. Since anodic oxidation has been proven to be an effective technique to prepare micro or nanostructures on Al alloys surface, this study proposes a novel and scalable multiple anodic oxidations method with gradient current densities for fabricating hierarchical micro-nanostructure film with appropriate roughness on Al alloys, while the SiO 2 -silane film reduced the surface free energy and enhanced the surface chemical inert state. As expected, the surface of Al alloys modified with the multiple anodic oxidations and SiO 2 -silane film has the most substantial hydrophobic properties, with contact angle up to 166°, rolling angle as low as 3.17°and excellent nonsticking effect of water droplets. This method enables the Al alloys surface to have excellent self-cleaning performance and corrosion resistance with protection efficiency up to 98.81 %. This multiple anodic oxidations method has a wide range of references for the modulation of micro-nanostructure on Al alloys surface and other metallic substrates to assemble superhydrophobic protective films.