Preparation of antifreeze and corrosion-resistant superhydrophobic coatings on the surface of TC11 titanium alloy by combining micro-arc oxidation and spraying methods

Abstract

Superhydrophobic coatings, owing to their “zero-energy consumption” and “multifunctional” characteristics, exhibit great application potential in the field of anti-icing. However, most existing studies rely on either micro-arc oxidation (MAO) or spraying techniques alone: the former provides a protective ceramic layer but offers limited functional tunability, while the latter enables surface functionalization but suffers from poor adhesion and durability. In this work, an innovative combination of MAO and spraying was employed. A ceramic intermediate layer was first formed on the surface of TC11 alloy via MAO, followed by spraying fluorinated silica nanoparticles (SiO₂ NPs-PFDTES) and epoxy resin to construct a composite coating with high adhesion, achieving excellent corrosion resistance and anti-icing performance. The surface wettability, layered morphology, elemental distribution, self-cleaning ability, corrosion resistance, and anti-icing mechanism were systematically investigated. The results demonstrate that the composite coating exhibits remarkable superhydrophobicity (WCA = 155.2 ± 0.2°, SA = 1.1 ± 0.1°). Electrochemical tests revealed that the impedance modulus |Z|_0.01 and charge transfer resistance (R_ct) of the coating increased by 1–2 orders of magnitude compared to the substrate, with an inhibition efficiency (η) as high as 98.5 %. Furthermore, dynamic icing experiments revealed that the composite coating achieves significant anti-icing effects by reducing thermal conductivity, contact area, and nucleation sites on the surface. This approach provides a new strategy for designing superhydrophobic coatings that balance strong adhesion with multifunctionality.