Influence of UV light on the corrosion behavior of AA6061-T6 in a CMA solution

The effect of ultraviolet (UV) light illumination on the corrosion behavior of AA6061-T6 in an alkaline snowmelt-agent solution (CMA solution) was investigated using electrochemical and spectroscopic techniques. The corrosion products and passive films formed under different exposure conditions were n-type semiconductors. Exposure for 1 and 2 weeks facilitated the corrosion process. Under UV light illumination, the extent of corrosion and size of corrosion pits were larger than those in the dark; this was attributed to the facilitation of the dissolution of AlFeSi intermetallics and formation of fewer oxides such as Al2O3 under UV light illumination. After exposure for 4 weeks, under UV light illumination, the formation of passive films was fewer defects, and more compact structures offered more protection to the aluminum substrates, resulting in slightly suppressed corrosion.