Raman Spectroscopic Study on Mechanism of Aluminum Triphosphate Pigment

应用拉曼光谱研究了含有防锈颜料涂装特性的钢样 ,在此基础上探讨了三聚磷酸铝防锈颜料对A3钢的保护机理 .三聚磷酸铝溶解后能到达钢样表面 ,其离子可与铁离子化合形成三聚磷酸铁 .三聚磷铁能缓慢地通过化学键牢固地附着在钢样表面 ,最终在钢表面形成一层隔绝腐蚀介质和钢样的紧蜜保护膜阻止了腐蚀的继续发生从而达到保护的目的The painted steel sample whose coating contained anticorrosive pigment has been investigated by Raman spectroscopy.The protective mechanism of aluminum triphosphate pigment for A3 steel is proposed as follows: Aluminum triphosphate can be dissolved and arrive at the surface of the steel.The dissolved triphosphate ions can complex with ferric ions.And the new products,namely ferric triphosphate,can strongly adhere at the surface of the steel by chemical bonds slowly.At last,a compact protective film,which effectively separates the steel substrate from the aggressive media,is formed at the steel surface.作者联系地址：中国科学院福建物质结构研究所,中国科学院福建物质结构研究所,中国科学院福建物质结构研究所,中国科学院福建物质结构研究所,中国科学院福建物质结构研究所 福建厦门361012 ,福建厦门361012 ,福建厦门361012 ,福建厦门361012 ,福建厦门361012Author's Address: Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences,Xiamen 361012,Chin

Electrochemical Impedance Spectroscopy Study on A3 Steel in Anti-corrosive Pigment Extract Solution

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 .防蚀颜料的溶解度大小是决定它的缓蚀性能优劣的重要因素之一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.作者联系地址：中科院福建物质结构研究所二部!福建厦门361012,中科院福建物质结构研究所二部!福建厦门361012,中科院福建物质结构研究所二部!福建厦门361012,中科院福建物质结构研究所二部!福建厦门361012,中科院福建物质结构研究所二部!福建厦门361012,厦门大学固体表面物理化学国家重点实Author's Address: 1.Fujian Inst. of Res. on the Structure of Matter, Chinese Academy of Scie., Xiamen, 361012, China; 2. State Key Lab. for Phys