Scaling the productivity of laser structuring processes using picosecond laser pulses at average powers of up to 420?W to produce superhydrophobic surfaces on stainless steel AISI 316L

摘要

We investigate the approach to scale up the productivity of the laser-based generation of superhydrophobic surfaces by means of increased average laser powers to enhance the surface structuring rates. Polished surfaces (mean roughness depth SRz?=?0.076?μm) of stainless steel AISI 316L were processed with a laser delivering 8?ps long pulses with a constant pulse energy of 1.4 mJ at pulse repetition rates of 100?kHz or 300?kHz corresponding to average laser powers of 140?W or 420?W, respectively. When the feed rate for the corresponding pulse repetition rate is adjusted in a way to result in a similar temperature increase due to heat accumulation effects and the re-deposition of nanoparticles formed during processing is avoided, comparable surface structures with similar wetting behavior are obtained.