铝合金表面的缓蚀作用研究

Study of corrosion inhibition performance on aluminum alloy surface

首先借助扫描电镜观察了铝合金表面经不同pH水溶液腐蚀后的微观变化。SEM结果表明,在酸、碱条件下因腐蚀机理的不同,铝合金表面的微观变化也有明显差异。同时研究了常用的5种表面活性剂和2种工业缓蚀剂的缓蚀作用。实验结果表明,在pH=2的酸性条件下,表面活性剂中C12～14烷基糖苷(APG)、椰油脂肪酸二乙醇酰胺(6501)和烷基苯磺酸钠(LAS)的缓蚀效果较好;pH=9的碱性条件下,APG和6501的缓蚀效果较好;综合分析APG的缓蚀作用最佳;而对于2种工业缓蚀剂,在酸、碱条件下均有一个最佳缓蚀浓度。

Aluminum alloy surface after treating with aqueous solution under different pH was observed by means of scanning electron microscope （SEM）. The SEM image showed that aluminum alloy surface was significantly different under acid or alkaline condition because of different corrosion mechanism. The corrosion inhibition performance of five surfactants and two commercialized corrosion inhibiting agents were studied. Results showed that the corrosion inhibition effect of C12-14APG,cocofatty acid diethanol amide （6501） and LAS on aluminum alloy surface is excellent at pH = 2, while under pH = 9, only C12-14APG and 6501 show satisfactory corrosion inhibition effect. Among all the five kinds of surfactants under testing, C12-14 APG shows the best corrosion inhibition performance. The optimum concentration for two commercialized corrosion inhibitors differs with pH condition as well.