Novel Coating Systems for Corrosion Protection of Aluminum Alloys and Composites in Marine Environment

摘要

Newly developed vanadia, ceria and molybdate-based fluoropolymer coating systems were proposed as alternatives to epoxy-based fluoropolymer commercial coating systems. The performance of the new coating systems were compared with clear and pigmented epoxy-based fluoropolymer coating systems from corrosion protection, adhesion and durability points of view. EIS and polarization measurements of AA6061 T6-10% Al_2O_3 composite, coated with the previous coating systems, were investigated in 3.5% NaCl under scratched conditions. The corrosion rates of epoxy-treated clear increased dramatically after less than one month of exposure in NaCl. The new coating systems showed outstanding corrosion resistance even after two months under scratched coating conditions. The durability of such new coatings using salt spray chamber test was very promising (> 2000h).