Laser texturing of materials and surface hydrophobicity

In the present study, laser surface texturing of polycarbonate sheet, alumina tile, and phosphorous bronze coupons are presented. The laser-treated layer characteristics, including surface morphology and hydrophobicity, treated layer metallurgy, microhardness, and residual stress formed are assessed using the analytical tools. The findings revealed that all the substrate materials considered are free from surface asperities and defect sites, such as large cavities and micro-cracks, after the laser treatment process. Laser texturing forms micro-/nano-poles at the surface. The use of high-pressure nitrogen assisting gas causes nitride species formation at the surface while lowering the surface energy. Micro-/nano-size texture and low surface energy significantly improves the hydrophobicity of the laser-textured surface. The residual stress determined is compressive and less than the yielding limit of the substrate materials textured.