Atmospheric Corrosion Behavior of Typical Aluminum Alloys in Low-Temperature Environment

The atmospheric corrosion behavior of type 2024, 5083, 6061, and 7075 aluminum alloys in the Antarctic environment was investigated by outdoor exposure tests and indoor characterization. After one year of exposure to the Antarctic atmosphere, significant differences in surface corrosion states were observed among the specimens. The results revealed that the corrosion rate of the 2024 aluminum alloy was the highest, reaching 14.5 g/(m2<middle dot>year), while the 5083 aluminum alloy exhibited the lowest corrosion rate of 1.36 g/(m2<middle dot>year). The corrosion products formed on the aluminum alloys exposed to the Antarctic environment were primarily composed of AlOOH and Al2O3. In the Antarctic atmosphere environment, the pits were dominated by a freezing-thawing cycle and salt deposition. The freezing-thawing cycle promotes the wedge effect of corrosion products at the grain boundary, resulting in exfoliation corrosion of high-strength aluminum alloys.