Preparation and mechanical durability of EP-SiO₂ composite superhydrophobic coatings

Abstract The mechanical durability of superhydrophobic coatings is a crucial performance limitation, prompting the development of composite superhydrophobic coatings via epoxy resin scraping and SiO 2 suspension spraying at different concentrations. This work systematically investigates the effects of SiO 2 concentration and coating thickness on wettability and wear resistance, providing the wear mechanisms. Results indicate that SiO 2 concentration significantly impacts initial wettability, with a 10 wt% concentration achieving a water contact angle of 158.7° and a sliding angle of 2.6°, demonstrating outstanding super-hydrophobicity. Mechanical durability is influenced by both SiO 2 concentration and coating thickness. A combination of 8 wt% SiO 2 and a 400 μm coating thickness substantially improves wear resistance, exhibiting minimal degradation after 50 wear cycles and demonstrating excellent mechanical durability. Furthermore, the coating exhibits good substrate adhesion, self-cleaning ability, and low-temperature performance, suggesting broad applicability in complex environments. This work offers valuable guidance for optimizing the design and application of superhydrophobic coatings.