Surface wettability is one of the most important surface properties. Its characterisation and modification enables us to use functional surfaces in different engineering applications. In this thesis, we focus on characterization of surface wettability after laser texturing in three different atmospheres: air, argon and nitrogen. We made a detailed revew of the literature in the field of different methods for characterization of superhydrophobic surfaces. Further, the wettability of laser textured surfaces was characterized by using the capillary emptiying method. We used water and ethanol to fill the capillary. We processed six areas of stainless steel by using a nanosecond fiber laser (wavelength of 1060 nm). Within each area, we have changed the scan line separation and/or average power of the laser beam. Samples became more hydrophobic over time, but stayed hygrophilic. Our resoults show, that areas with similar energy per area, express different wettability. The results show that the processing atmosphere, has significant influence on the surface wettability of the areas, processed with the same laser parameters. The key finding for this thesis is that it is possible to produce superhygrophilic surfaces by using a nanosecond fiber laser and that such surface, stays superhygrophilic by time.
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