Speaker
Description
Functional metallic surfaces with tailored wettability are of increasing interest for applications requiring enhanced corrosion resistance, self-cleaning behaviour, and reduced fouling. While laser texturing and chemical functionalization are established approaches for producing hydrophobic metallic surfaces, their combined effect remains poorly understood. Addressing this challenge is essential for developing robust and scalable processes for functional steel surfaces with tailored wetting behaviour.
This contribution presents a hybrid laser–chemical process using IR-ps-laser pulses for the localized anchoring of stearic acid on stainless steel surfaces. Four surface conditions, including an unstructured reference and three ps laser-generated topographies (LIPSS, bumpy structures, and big bumpy structures), were investigated. Stearic acid was applied using different deposition strategies before selective laser-assisted anchoring. The influence of surface topography, laser energy input, deposition method, and post-treatment on the resulting wettability was systematically evaluated.
The proposed hybrid process transforms initially hydrophilic laser-structured surfaces into hydrophobic and superhydrophobic surfaces with contact angles up to more than 150°. The results demonstrate that the achievable wettability is governed by the interplay between the initial surface topography and the laser-assisted chemical functionalization. Furthermore, the process window for stable functionalization is strongly influenced by the applied laser energy, while the durability of the hydrophobic effect depends on the underlying surface morphology.
Ongoing work focuses on evaluating the long-term stability and corrosion performance of the functionalized surfaces as well as extending the concept to different liquid media. The presented hybrid laser–chemical approach provides a promising route towards robust, application-specific surface functionalization of steel components.
