Enhanced superhydrophobicity of acrylic polyurethane coatings by femtosecond laser ablation

In recent years, superhydrophobic coatings on aircraft surfaces have garnered significant attention due to their ability to protect the surface from corrosive source like raindrops, sand, and gasoline, etc. However, to date, research on enhancing the hydrophobicity of commercial aviation coatings on aircraft Al surface is still insufficient. In the present study, the femtosecond laser ablation technique is used to texture acrylic polyurethane coatings (denoted as APU) which has been used in the aviation field to achieve a superhydrophobic surface. The relationship between micro-/nanostructures fabricated on the coatings under different laser processing parameters and the corresponding hydrophobicity was studied. The microcone-structured superhydrophobic APU surface prepared under the optimal parameters exhibited a contact angle of 151.2° and a sliding angle of 4.2°. Durability test results show that the APU surface remains at a contact angle of more than 150° after a 140° high-temperature test and 6 h acid-base solution immersion, indicating good chemical and thermal stability. The adopted femtosecond laser fabrication technology and the resultant superhydrophobic coating in the present study may have potential applications to protect aircraft parts from corrosion damage.