Alteration of wettability and inhibition of corrosion in narrow aluminium 7075 gaps by thin polymer films

The admicellar polymerization process was adapted to deposit polystyrene (PS) and poly(methyl methacrylate) (PMMA) onto aluminium 7075 surfaces. Characterization of the films was performed using FTIR spectroscopy, scanning electron microscopy and atomic force microscopy. Dynamic contact angles confirmed the hydrophobic nature of modified aluminium substrates. Artificial crevices made from coated aluminium 7075 coupons were developed to simulate the crevices formed on aircraft. Water uptake measurements showed that PS delayed water penetration in the crevices for almost 4 h. Accelerated corrosion tests revealed the protective characteristics of PMMA. Image analysis was used to quantify the extent of corrosion in the crevice.