Laser-Patterned Super-Hydrophobic Pure Metallic Substrates: Cassie to Wenzel Wetting Transitions

摘要: A femtosecond laser was used to create microstructures on very pure metal surfaces. The irradiated samples initially showed super-hydrophilic behavior. With time and exposure ambient air the contact angle increased about 160° with low hysteresis. surfaces supported Cassie Wenzel wetting states, depending technique deposit water droplets. created surface morphologies were idealized a geometric model that is an assembly of densely packed cylindrical pillars semispherical caps. Using this for calculation roughness, theoretical Young 99° calculated all from Cassie–Baxter equations. While value significantly differs measured hydrophilic angles polished metallic samples, it indicates laser-induced reaction must be responsible evolution super-hydrophobic ones phenomenon in...