7B04铝合金在模拟海洋大气环境下的腐蚀行为

发布时间：2018-02-23 04:27

本文关键词： B铝合金大气腐蚀薄液膜盐沉积量相对湿度　出处：《航空材料学报》2017年01期 　论文类型：期刊论文

【摘要】：海洋大气环境下铝合金的腐蚀本质上是薄液膜下的电化学腐蚀,与本体溶液中的腐蚀有很大不同,腐蚀速率与薄液膜的厚度及成分有关。建立并实验验证了薄液膜厚度、大气相对湿度和铝合金表面盐沉积量3者之间的关系,研究7B04铝合金在不同厚度和不同Na Cl浓度薄液膜下的电化学性能。结果表明,薄液膜下7B04铝合金的自然腐蚀电位较本体溶液中更容易达到稳定,且电位更正,自然腐蚀速率更大;液膜厚度减小,7B04铝合金阴极极化电流密度增加,阳极反应受到抑制;薄液膜中Na Cl浓度升高,7B04铝合金的自然腐蚀电位降低,腐蚀速率上升,而阴阳极极化过程受Na Cl浓度变化影响不大,当Na Cl质量分数达到5%后,自然腐蚀电位基本不再变化。
[Abstract]:The corrosion of aluminum alloy in marine atmosphere is essentially electrochemical corrosion under thin liquid film, which is very different from corrosion in bulk solution. The corrosion rate is related to the thickness and composition of thin liquid film. The relationship between atmospheric relative humidity and salt deposition on aluminum alloy surface is studied. The electrochemical properties of 7B04 aluminum alloy under different thickness and different NaCl concentration thin liquid film are studied. The natural corrosion potential of 7B04 aluminum alloy under thin liquid film is more stable than that in bulk solution, and the potential correction results in higher natural corrosion rate, and the thickness of liquid film decreases and the cathodic polarization current density of 7B04 aluminum alloy increases, and the anodic reaction is inhibited. The natural corrosion potential of 7B04 aluminum alloy decreases and the corrosion rate increases with the increase of NaCl concentration in thin liquid film. However, the change of NaCl concentration has little effect on the process of anode and cathode polarization. When the mass fraction of NaCl reaches 5%, the natural corrosion potential basically does not change.
【作者单位】：海军航空工程学院青岛校区;
【基金】：国家自然科学基金(51075394,51375490)
【分类号】：TG178

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