Laser-Textured Superbiphilic Aluminum Surfaces: Fabrication, Wettability Evolution, and Potential for Flow Boiling Enhancement

This study investigates the fabrication of laser-textured superbiphilic surfaces on Aluminum for potential flow boiling enhancement. A nanosecond fiber laser was used to generate various micro-patterns, with surface morphology and wettability evolution characterized over a 20-day period using SEM, EDS, profilometry, and contact angle measurements. Results demonstrate the successful creation of surfaces with extreme and stable wettabilities. Superhydrophobic regions were achieved, with one spot evolving from a hydrophilic state (51.2°) to a superhydrophobic state (150.2°) after 12 days. Concurrently, robust superhydrophilic regions ( <5°) were created. This temporal evolution is attributed to specific micro-textures (Sa = 7.392 µm) enabling air trapping and hydrocarbon adsorption. Superhydrophilicity was linked to a more extensive oxide layer (O = 53.05 wt% vs. 30.85 wt%). These findings highlight the potential of laser texturing for engineering superbiphilic surfaces.