This study examines the effects of pulse power and number of laser passes on the line roughness of titanium surfaces during nanosecond laser texturing, with implications for the fabrication of superhydrophobic surfaces. We texture titanium specimens (...
This study examines the effects of pulse power and number of laser passes on the line roughness of titanium surfaces during nanosecond laser texturing, with implications for the fabrication of superhydrophobic surfaces. We texture titanium specimens (30 mm × 30 mm × 2 mm) under various pulse power levels (300, 900, ᅠᅠᅠᅠᅠᅠᅠ and 1500 mW) and pass counts (3, 6, 9, and 12). Next, we quantitatively measure the line roughness in both the parallel and perpendicular directions using confocal microscopy. The results show that increasing the pulse power exerts a more significant effect on the roughness compared with increasing the number of passes. At 900 mW, the roughness increases by ~49.3% (perpendicular) and ~76.9% (parallel) relative to the baseline (300 mW, three passes), whereas increasing the number of passes from three to nine yields smaller increases. SEM confirmed deeper/wider ablation at higher power levels. These results suggest that pulse power is the dominant factor in micro/nanostructure formation. According to the Wenzel and Cassie–Baxter models, enhanced roughness is crucial for achieving superhydrophobicity. Future studies shall investigate the correlation between surface roughness and contact angle and assess the synergistic role of SAM coatings in process optimization