Silane Films Modified with Yttrium Oxide Nanoparticles for Improved Corrosion Resistance of AA6061-T6

The present work strives to evaluate the corrosion resistance of aluminum alloy (AA)6061-T6 (UNS A96061) pretreated with bis-1,2-[triethoxysiyl]ethane silane (BTSE) solution containing different contents of yttrium oxide (Y₂O₃) nanoparticles. The corrosion resistance of the pretreated AA6061-T6 substrates was investigated with potentiodynamic polarization curves and the neutral salt spray (NSS) test. The morphologies of the silane film were observed using scanning electron microscopy (SEM). The results indicated that the presence of small amounts of Y₂O₃ nanoparticles in BTSE solutions can increase the corrosion resistance of the silane films in 3.5% sodium chloride (NaCl) solution. Y₂O₃ nanoparticles do not change the behavior of the electrode reaction. The formed silane film acts as a physical barrier for the protection of aluminum alloy. The SEM images indicated that the surface morphologies of silane films formed were flat and compact, when the contents of the Y₂O₃ nanoparticles in BTSE solutions were between 10 ppm and 20 ppm.