Atmospheric Corrosion of AZ31B Magnesium Alloy in the Antarctic Low-Temperature Environment

• Published in: Acta metallurgica sinica : English letters 2023-09, Vol.36 (9), p.1421-1432
• Main Authors: Shi, Xi-Zhao, Cui, Zhong-Yu, Li, Jie, Hu, Bing-Chen, An, Yi-Qiang, Wang, Xin, Cui, Hong-Zhi
• Format: Article
• Language: English
• Subjects: Atmospheric corrosion; Characterization and Evaluation of Materials; Chemistry and Materials Science; Corrosion and Coatings; Corrosion products; Corrosion rate; Electrodes; Exposure; Humidity; Low temperature environments; Magnesium alloys; Magnesium base alloys; Magnesium carbonate; Materials Science; Metallic Materials; Morphology; Nanotechnology; Organometallic Chemistry; Pitting (corrosion); Spectroscopy/Spectrometry; Tribology; Uniform attack (corrosion)
• ISSN: 1006-7191; 2194-1289
• DOI: 10.1007/s40195-023-01561-4

In this work, the outdoor corrosion behavior of AZ31B magnesium alloy in the Antarctic atmospheric environment was investigated. The surface corrosion state of the specimens exposed to the Antarctic atmosphere for 1 month and 24 months differ significantly. The corrosion rate after 1 month during the summer season was 19.82 g/m 2 ·year and it decreased to 13.87 g/m 2 ·year after two years’ exposure. Corrosion is initiated with pitting corrosion and then evolved to uniform corrosion with prolonging exposure time. The skyward surface exhibited a much severe corrosion than that of the groundward surface, attributed to the long-term existence of the adsorbed electrolyte layer. The corrosion products formed on the alloy exposed in Antarctica environment were MgCO 3 ·3H 2 O, MgCO 3 ·5H 2 O and Mg 2 CO 3 (OH) 2 ·0.5H 2 O, with the MgCO 3 ·3H 2 O as the dominant phase in the initial stage and the Mg 2 CO 3 (OH) 2 ·0.5H 2 O as the dominant phase after long-term exposure.