摘要
通过对铝合金部件服役环境的分析,发现Cl-是加速点蚀的主要原因之一.根据热力学理论,推导出Al3+等阳离子水解反应的平衡pH值计算公式,并定性的分析出OCC内溶液的pH值比外部的低,同时,通过电化学分析,发现OCC内的Cl-是富集的.OCC内这种强酸性环境可使蚀孔内壁金属处于活性态,大面积阳极氧化膜表面则处于钝态,从而加速点蚀孔的扩大和加深.
It was found that Cl- is one of pitting corrosion accelerated factors of aluminum alloy through analyzing service environment in coastal areas. According to thermodynamics theory, the equilibrium pH value equation was deducted. It was qualitatively analyzed pH value is lower in OCC than out OCC. It was found through electrochemical analysis that Cl- concentration is higher in OCC. Pitting is deepened and widened because the alloy is activated in acid OCC and the anode oxidation coating out of OCC is inactive.
出处
《装备环境工程》
CAS
2004年第3期36-39,共4页
Equipment Environmental Engineering
关键词
铝合金
点蚀
PH值
Cl^-
aluminum alloy
pitting corrosion
pH value
Cl-
