Corrosion and Antifouling Behavior of a New Biocide-Free Antifouling Paint for Ship Hulls Under Both Artificially Simulated and Natural Marine Environment

This study involved covering naval steel samples with a biocide-free, innovative antifouling coating, which were subsequently immersed in either artificial seawater or a Greek maritime environment for durations ranging from 1 to 50 weeks. The objective was to assess the efficacy of the coating as an anticorrosion and antifouling barrier on the steel samples. Non-coated samples were analyzed alongside the coated samples for comparative purposes. The findings indicate that a reduction in coating thickness during static immersion in laboratory settings leads to the removal of precipitated corrosion products, exposing a fresh layer of "pristine" coating. This layer decreases the corrosion rate by almost 90% throughout extended immersion durations. The efficacy of the coating is validated through trials conducted in natural maritime environments, demonstrating an operational performance of 99% for the coated samples after 50 weeks of continuous exposure to seawater. In fact, the coated samples showed only soft fouling, in contrast to the uncoated samples which were characterized by a strong presence of hard fouling within a short period of time after immersion.