针对航空铝合金材料在服役过程中因恶劣环境而导致材料腐蚀的问题,通过分析腐蚀形貌、腐蚀坑开口面积、腐蚀深度、点腐蚀坑数量、pH值、腐蚀产物等变化,研究2xxx航空铝合金在不同腐蚀环境(3.5%NaCl水溶液、模拟油箱积水溶液和潮湿空气)中的腐蚀行为和机理.结果表明,在3.5%NaCl水溶液中,铝合金试样表面腐蚀坑的产生主要发生在前24 h内,其最大腐蚀坑深约为45μm,而在72~120 h,随预腐蚀时间的延长,腐蚀坑深度、个数的增加并不明显;铝合金试样在模拟油箱积水环境中的腐蚀规律与在3.5%NaCl水溶液中的相似,但腐蚀坑最大开口面积和腐蚀坑的个数明显减少;与前两种环境相比,试样在潮湿空气环境中的腐蚀程度明显减小,腐蚀坑总体个数最少,最大腐蚀坑深约在20μm以内,最大开口面积约在5000μm2左右,且随着腐蚀时间的增长,腐蚀坑之间的深度差距越来越小.%Aiming at the corrosive material problems caused by harsh environment during the service of aviation aluminum alloy materials,research on the corrosion behavior and mechanism of 2xxx aviation aluminum alloys servicing in different corrosive environments(3.5% NaCl solution,wa-ter in fuel tank and wet air)was conducted based on the analyses about the corrosion morphology, openning areas,depths and quantity of the pits,pH values and corrosion products.Results show that corrosion products are mainly found in the first 24 hrs for specimens in 3.5% NaCl solution with the biggest pit depth about 45 μm,with the increase of the corrosion time between 72 ~120 hrs,the in-crease of pit depths and quantities are not obvious.The corrosion behavior for specimens in water in fuel tank was similar to that in NaCl solution,but the pit openning areas and quantities decrease dra-matically.The corrosion extents for specimens in the wet air decrease compaired with the other two corrosive environments with the least pit quantity,the deepest pit depth is lower than 20 μm and the biggest pit openning area is around 5000 μm2 ,the differences among pit depths decrease with the in-crease of corrosion time.
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