Simple Fabrication of Hierarchical Micro/Nanostructure Superhydrophobic Surface with Stable and Superior Anticorrosion Silicon Steel via Laser Marking Treatment

To improve the weak corrosion resistance of silicon steel to acid solution and alkaline solution with high temperature, a stable hierarchical micro/nanostructure superhydrophobic surface with myriad irregular micro-scale hump and sheet-like nanostructure was successfully prepared on silicon steel by a simple, efficient and facile operation in large-area laser marking treatment. The morphology, composition, wettability of the as-prepared surface were studied. The superhydrophobic performance of the surface was investigated as well. Additionally, the corrosion resistance of the superhydrophobic surface to acidic solutions at room temperature and alkaline solutions at high temperature (80 °C) was carefully explored. The corrosion resistance mechanism was clarified. Moreover, considering the practical application of the surface in the future, the hardness of the hierarchical micro/nanostructure superhydrophobic surface was studied. The experimental results indicate that the hierarchical micro/nanostructure surface with texture spacing of 100 µm treated at laser scanning speed of 100 mms/presents superior superhydrophobicity after decreasing surface energy. The contact angle can be as high as 156.6°. Additionally, the superhydrophobic surface provide superior and stable anticorrosive protection for silicon steel in various corrosive environments. More importantly, the prepared structure of the surface shows high hardness, which ensures that the surface of the superhydrophobic surface cannot be destroyed easily. The surface is able to maintain great superhydrophobic performance when it suffers from slight impacting and abrasion.