Surfaces with unique wettability are used in various fields of technology, in agriculture, food industry and medicine. The animals and plants exploit the hydrophilicity or hydrophobicity for their survival. The most famous example of the superhydrophobic surface in nature is the lotus leaf, which has also the self-cleaning ability and in this way, it prevents the growth of bacteria and microorganisms. In this BSc thesis, we demonstrate that superhydrophobic metal surfaces can be produced by a combination of laser texturing and their subsequent low-temperature annealing in a contaminated furnace. Stainless steel samples were laser textured by using a fibre laser radiating 28-ns pulses with a wavelength of 1060 nm. The laser-processed samples were further annealed at 100 °C, 200 °C, 250 °C and 300 °C. Before, during and after annealing, we measured the contact and the roll-off angle of water droplet. The annealing was repeated in two furnaces at the same temperatures in order to identify the influence of the surrounding atmosphere on the hydrophilic-to-hydrophobic transition of the laser-textured samples. We found that this transition occurs due to the adsorption of organic contaminants that were present in the furnace.
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