20.500.12556/RUL-105246 Long-term influence of laser-processing parameters on (super)hydrophobicity development and stability of stainless-steel surfaces Controlling the surface wettability represents an important challenge in the field of surface functionalization. Here, the wettability of a stainless-steel surface is modified by 30-ns pulses of a Nd:YAG marking laser (λ = 1064 nm) with peak fluences within the range 3.3–25.1 J cm$^{−2}$. The short- (40 days), intermediate- (100 days) and long-term (1 year) superhydrophilic-to-(super)hydrophobic transition of the laser-textured surfaces exposed to the atmospheric air is examined by evaluating its wettability in the context of the following parameters: (i) pulse fluence; (ii) scan line separation; (iii) focal position and (iv) wetting period due to contact angle measurements. The results show that using solely a short-term evaluation can lead to wrong conclusions and that the faster development of the hydrophobicity immediately after laser texturing usually leads to lower final contact angle and vice versa, the slower this transition is, the more superhydrophobic the surface is expected to become (possibly even with self-cleaning ability). Depending on laser fluence, the laser-textured surfaces can develop stable or unstable hydrophobicity. Stable hydrophobicity is achieved, if the threshold fluence of 12 J cm$^{−2}$ is exceeded. We show that by nanosecond-laser texturing a lotus-leaf-like surface with a contact angle above 150° and roll-off angle below 5° can be achieved. laser surface engineering wetting superhydrophobic surfaces laser material processing surface modification laserski inženiring površin superhidrofobne površine laserske obdelave true false true Angleški jezik Slovenski jezik Članek v reviji 2018-11-14 08:45:40 2018-11-14 08:45:41 2022-08-18 03:43:14 0000-00-00 00:00:00 2018 0 0 15 str. iss. 11, art. 2240 Vol. 11 Nov. 2018 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 621.7(045) 1996-1944 10.3390/ma11112240 16343835 RAZ_Gregorcic_Peter_2018.pdf RAZ_Gregorcic_Peter_2018.pdf 1 E4DF33A4120912F3F8CB6C76310F1B38 bda99ec5a36dd8abe914c737b6e6a7930bc86a837f5dcc7e65ff2af14254379c e196b0d5-2830-11ec-a523-00155dcfd717 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=149499 https://www.mdpi.com/1996-1944/11/11/2240 1 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=115859 Fakulteta za strojništvo 0 0 0