Fabrication of Superoleophobic Aluminum Alloy with Hierarchical Micro/Nano Structures for Long-Term Corrosion Protection in Ethylene Glycol-Water Solutions

Abstract

Aluminum (Al) alloys are widely used in aerospace, automotive, and electronics industries due to their light weight and durability. However, their poor corrosion resistance has hindered further development, especially when in contact with oily solutions. In this work, a simple method was adopted to superoleophobic Al alloys with hierarchical micro/nano structures, including plasma electrolytic oxidation, hydrothermal treatment, and fluorination modification. The Contact Angle (CA) and Sliding Angle (SA) of water on the surface were measured to be 164.1° and 0.6°, and those of ethylene glycol-water solutions were 157.1° and 0.7°, respectively. The surface exhibited excellent low adhesion and self-cleaning properties. The electrochemical test results showed that compared with bare Al alloy, the corrosion current density of the superoleophobic surface decreased by 2 orders of magnitude, the charge transfer resistance (R_ct) increased by 3 orders of magnitude, and the corrosion inhibition efficiency reached 98.11%. Additionally, the superoleophobic surface still exhibited good corrosion resistance after 45 days of immersion. We believe that this work provides a novel perspective and theoretical support for the long-term durability of Al alloys in the ethylene glycol-water solution environment.