Ice accumulation on surfaces poses challenges in many fields. This issue can be effectively addressed with superhydrophobic surfaces that enhance the resistance against freezing. In this diploma thesis, we developed superhydrophobic surfaces on aluminum substrates using a combination of laser-texturing and hydrophobization, which successfully increased the resistance against freezing of impacting water droplets. The effectiveness of the surfaces was determined by measuring the contact angles and evaluating droplet rebound on them at various subcooled surface temperatures. The obtained results were compared with an untreated surface, focusing on the influence of humidity, temperature, and droplet impact velocity. All measured contact angles were above 160°, and the contact angle hysteresis did not exceed 5°. Relative humidity in the air significantly impacted the results. Increased humidity reduced the droplet rebound capability upon impact on a supercooled surface. Lowering the surface temperature mainly affected the droplet retraction phase, which was shortened due to faster droplet freezing. Higher droplet impact velocities resulted in larger maximum diameters during the impact and larger final diameters after freezing. The higher the velocity, the more the droplet splashed and disintegrated into smaller satellite droplets. The best resistance against freezing was demonstrated by a surface with an average channel depth and width of 26.8 μm and 26.8 μm, respectively, and a spacing between the channels of 50 μm.
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