摘要
应用EIS研究了A3钢在不同 pH值的磷酸锌或三聚磷酸铝 3.5 %NaCl提取液中的腐蚀行为 .结果显示 ,相同条件下 ,A3钢的电阻值随溶液 pH值增加而增加 ,电容值则相反 .在磷酸锌3.5 %NaCl提取液中 ,因磷酸锌的溶解度太小 ,没有足够的量对金属基底A3钢进行有效的保护 .在 pH值为 6的三聚磷酸铝 3.5 %NaCl提取液中 ,A3钢表现出较明显的缓蚀现象 ,可能是因为三聚磷酸根离子与腐蚀产物Fe2 + 、Fe3+ 络合并在钢表面形成了一层致密的保护膜 ,从而有效地阻止了腐蚀介质的进一步入侵 .
The corrosion behaviors of A3 steel in different pH, 3.5%NaCl, modified zinc phosphate and aluminum triphosphate extract solutions have been studied by EIS. Results show:(a) The resistance increases with the increase of pH value under the same circumstances, but the capacity is the reverse.(b) Zinc phosphate, because of its low solubility, shows no inhibitive performance for A3 steel in 3.5% NaCl extract solutions. (c) Aluminum triphosphate has good inhibitive performance for A3 steel in 3.5% NaCl extract solutions at a pH of 6, probably because the triphosphate ion can complex with the corrosion_product, such as ferric and ferrous ions, and form a compact protective film that separates effectively the steel substrate from the aggressive media at the steel surface. (d) The solubility of the anticorrosive pigment is one of the most important factors for its inhibitive performance.
出处
《电化学》
CAS
CSCD
2001年第3期345-350,共6页
Journal of Electrochemistry
基金
厦门大学固体表面物理化学国家重点实验室开放课题 (970 3)资助项目
