Topography, antisoiling and anticorrosion behavior of the superamphiphobic composite coating on 5083 aluminum alloy based on microarc oxidation

Abstract The inadequate corrosion resistance of aluminum alloys significantly limits their widespread application, thereby necessitating research on enhancing their resistance to corrosion and contamination. Superamphiphobic coatings present a promising solution to mitigate this issue. In this study, spraying technology was employed in conjunction with MAO to create a superamphiphobic composite coating with exceptional corrosion resistance on the surface of 5083 aluminum alloy. The morphology, superamphiphobic characteristics, and corrosion resistance of the material were comprehensively assessed. The corrosion current density of the optimal superamphiphobic composite coating obtained via MAO followed by spraying with modified TiO 2 nanoparticles ( I corr = 9.23 × 10 −13 A·cm −2 ) was six and three orders of magnitude lower than that of 5083 aluminum alloy and the unmodified MAO coating, respectively. Furthermore, the coating exhibited a large capacitive arc diameter, enhanced charge-transfer resistance, and high |Z| value at a low frequency (0.01 Hz), signifying its excellent corrosion resistance. Additionally, the coating exhibited superamphiphobic properties with high contact angle (>150°) and low sliding angle (<10°), promoting nonwetting behavior toward various liquids with different surface tensions. This behavior can be attributed to the micro-nanostructure, which significantly enhances surface hydrophobicity and oleophobicity. Moreover, the coating demonstrated dynamic self-cleaning and antisoiling capabilities. These attributes underscored the ability of the coating to exhibit super-repellency, antisoiling performance, ultralow surface energy, and interfacial adhesion forces. Finally, the superamphiphobic composite coating demonstrated noteworthy thermal and chemical stabilities—as evaluated through heat, acid, and alkali resistance tests—thereby affirming its practical viability.