20.500.12556/RUL-171903 Adhezija ledu na hidrofobnih površinah z lokalnimi nepravilnostmi Ice adhesion strength on hydrophobic surfaces with local defects Adhezija ledu na kovinskih površinah predstavlja pomemben tehnični izziv v številnih industrijskih panogah, saj bistveno vpliva na učinkovitost in varnost sistemov. V diplomski nalogi smo raziskali možnosti za zmanjšanje adhezije ledu na aluminijastih površinah z uporabo kombinirane metode lokalnega laserskega teksturiranja in nanosa hidrofobnega PDMS premaza. Na površinah smo izdelali kvadratne strukture različnih velikosti (150, 225, 300 µm) in središčnih razdaljah (0,5–4,0 mm), nato pa jih hidrofobizirali z 10 wt. % PDMS premazom. Na namensko razviti eksperimentalni progi smo izvedli meritve adhezijske strižne trdnosti ledu z uporabo horizontalnega strižnega testa. Najnižjo adhezijsko trdnost 28,0 ± 8,4 kPa smo dosegli pri strukturah z dolžino stranice 150 µm in središčno razdaljo 2,5 mm, kar predstavlja 64 % zmanjšanje v primerjavi z gladko PDMS površino ter 87 % zmanjšanje v primerjavi z neobdelanim aluminijem. Definirali smo parameter dolžinske zasedenosti in razvili matematični model za napoved adhezijske trdnosti ledu pri različnih konfiguracijah struktur. Ugotovili smo, da nizka adhezija ledu ni neposredno povezana z visoko hidrofobnostjo površin, temveč je ključnega pomena ustrezna kombinacija velikosti in razporeditve mikrostruktur za doseganje ravnovesja med zmanjšano kontaktno površino in koncentracijo napetosti. Ice adhesion on metallic surfaces represents a significant technical challenge in various industrial sectors, as it strongly affects system efficiency and safety. In this thesis, strategies for reducing ice adhesion on aluminum surfaces were investigated using a combined approach of localized laser-texturing and deposition of a hydrophobic PDMS coating. Square microstructures of different sizes (150, 225, 300 μm) and center-to-center distances (0.5–4.0 mm) were fabricated on the surfaces and subsequently hydrophobized with a 10 wt.% PDMS layer. Measurements of ice shear adhesion were performed on a specially developed experimental setup using a horizontal shear test. The lowest ice adhesion of 28.0 ± 8.4 kPa was achieved for structures with a side length of 150 μm and a center-to-center distance of 2.5 mm, corresponding to a 64% reduction compared to a smooth PDMS surface and an 87% reduction compared to untreated aluminum. A linear surface coverage parameter was defined, and a mathematical model was developed to predict ice adhesion for different structural configurations. It was found that low ice adhesion is not directly correlated with high surface hydrophobicity; rather, an appropriate combination of microstructure size and spacing is critical to achieving a balance between reduced contact area and stress concentration. protizmrzovalne površine adhezija ledu lokalne nepravilnosti lasersko strukturiranje PDMS premaz omočljivost hidrofobne površine icephobic surfaces ice adhesion local defects laser texturing PDMS coating wettability hydrophobic surfaces true false false Slovenski jezik Angleški jezik Diplomsko delo/naloga 2025-09-04 08:31:23 2025-09-04 08:31:26 2025-09-25 03:46:44 0000-00-00 00:00:00 2025 0 0 XII, 54 f. 2025 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 621.565:66.02:534.219(043.2) 275368 249214467 43848.pdf 43848.pdf 1 BC47D9A5B0A1E40B47D74AA2143F3430 61c2a289451e9ccb272a9bf45570a78b57d7e58cd8be119b32c3106af518f9f2 a2f75ec3-8958-11f0-9328-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=215469 Fakulteta za strojništvo 0 0 0