【作者】 朱涛；

【导师】 董泽华；

【作者基本信息】 华中科技大学 ， 应用化学， 2011， 硕士

【摘要】 钢筋混凝土腐蚀的研究工作,已经开始引起国内外广泛关注。国内外大量学者从事阻锈剂的研究,但对有机缓蚀剂的研究仍处于起步阶段。同时,对有机缓蚀剂抑制金属点蚀过程的作用机理也不成熟,因此,基于此目的,本文探讨了四乙烯五胺对16Mn钢在模拟碳化孔溶液中的作用机理,通过对该物质的研究,能够找到关于胺类缓蚀剂的共同特点,从而指导有机缓蚀剂的实际应用。分析结果表明,电化学噪声能有效的区别16Mn钢在在模拟孔溶液中的点蚀过程的三个阶段:钝化过程,亚稳态点蚀过程,稳态点蚀过程。16Mn钢在点蚀过程中,电化学噪声电阻呈现指数形式递减,形核速率呈抛物线形式变化,先增大后减小,点蚀事件个数会减少,但是点蚀事件产生的电流峰幅值会增大。在出现稳态点蚀后(有腐蚀产物覆盖在蚀点上),低浓度亚硝酸根离子由于无法进入蚀孔的内部,因此对点蚀抑制作用并不明显,但是会排挤掉吸附在腐蚀产物上的氯离子。当浓度增加到一定量,此时,离子扩散主要受浓差变化的影响,亚硝酸根离子很快扩散到蚀孔内部,点蚀过程抑制作用非常明显。点蚀电量能更有效的反应出亚硝酸根离子对点蚀过程的抑制作用。电化学阻抗表明,四乙烯五胺对16Mn钢抑制作用非常明显。钼酸根离子与四乙烯五胺的协同作用研究表明,四乙烯五胺能够在金属表面形成吸附膜,阻止氯离子的侵蚀,同时,钼酸根离子能够使钝化膜变的更加致密。电化学噪声测试中,电流峰宽变化能有效反应无机缓蚀剂的缓蚀效率,但是电流峰宽变化不能准确评价有机缓蚀剂四乙烯五胺对点蚀过程的缓蚀能力。更多还原

【Abstract】 Study on the corrosion of reinforced concrete has attracted wide international attention. Many scholars engaged in this field. However, the research about the organic corrosion inhibitors is still in its infancy. Meanwhile, the process of the organic inhibiting pitting corrosion is not mature. Therefore, we discuss the mechanism on the pitting corrosion of 16Mn carbon steel in simulated pore solution and test for the effect of amine inhibitors in order to find common characteristics of corrosion inhibitors on the amine to guide the practical application of organic corrosion inhibitor.The electrochemical noise resistance decreases in the exponential form if 16Mn steel is developing in the process of pitting, and the nucleation rate first increased and then decreased. The pitting events will be reduced. But the peak amplitude of the current will increase in the active process (corrosion product covering the eclipse point).Low concentrations of nitrite cannot enter the pit, so there is little effect on the pitting. But it will replace the adsorbed chloride ions on the corrosion products .When the concentration increased to a certain amount, the ion diffusion is mainly affected by concentration impacts, nitrite ion soon spread to the inside of the pitting.The pitting charge can respond to the nitrite ion on the role of pitting electrochemical noise process effectively. Electrochemical result indicates that TEPA can inhibit the process of pitting on 16Mn carbon steel. The synergy research on the molybdate ion and TEPA have shown that TEPA can absorb the film on metal surface to prevent erosion of chloride ions while MoO42- ions can make the passive film become more dense. Electrochemical noise tests illustrate that the current changes in the peak width can be effective response to the efficiency of inorganic corrosion inhibitors, which is not an accurate evaluation of TEPA on the inhibition ability of pitting corrosion process.更多还原