Controlling surface wettability and adhesive properties by laser marking approach

We provide a special microstructure to fabricate superhydrophobicity surface of aluminum alloy by laser marking method. The morphologies and wettability of the fabricated aluminum alloy surface are investigated through scanning electron microscopy (SEM) and the contact angle meter. The results indicate that the fabricated surface with irregular protrusions and pits shows excellent superhydrophobicity/hydrophobic. The surface texture of this microstructure is characterized by a contact angle of up to 156.4 degrees when the surface exhibits superhydrophobicity and a contact angle of up to 147.8 degrees when the surface exhibits hydrophobicity. Because the unidirectional processing of the laser makes the surface anisotropic, we discuss the wettability in this area. Moreover, we discuss the effect of wettability and adhesion at different scales on the fabricated surface. A series of data shows differences in related properties due to different laser texture scales. Differences in performance of the material can be applied in different field conditions. The fabrication technique is a promising method to provide superhydrophobic surface with potential applications including fluid transfer, fluid power systems, stain-resistant and anti-fouling surfaces, anti-creeping of oils, anti-contamination, and oil transport. More importantly, this novel surface structure further extends the application of aluminum alloys in industry.