Localized Corrosion and Phase Transformation of Simulated Archaeological Iron

在答案的模仿的考古学的铁的腐蚀性(0.06 摩尔· L ? 1 NaCl+0.03 摩尔· L ? 1 Na2SO4+0.01 摩尔· L ? 1 NaHCO3 ) 模仿土壤水作文被潜力调查动态极化，经常的潜在的极化，和模仿的堵塞房间(O.C ) galvanostatic 测试。X 射线衍射(XRD ) ，精力色散分光法(版本) ，和扫描电子显微镜(SEM ) 被用来学习腐蚀形态学和腐蚀产品的进化。目的是发现考古学的铁的转变过程，并且决定使氯化的腐蚀产品的分发。结果证明缝隙，洞，和隧道的存在在锈下面便于局部性的腐蚀；自动催化的效果增加 Fe2+ 的集中， 17 号元素氯的化学符号 ? ，并且 SO42 ? ，并且在缝隙和洞以内支持本地使发酸。同时，腐蚀产品的相变被结束借助于二个方法继续。一个人是铁的离子经由中间的缺酸料液(II )-Fe(III) 氢氧根盐被转变成 FeOOH 的不同类型(我。e。格林生锈) ；其它是 Fe2+ 离子在缝隙和洞被转变成 FeCl2， FeCl3，和橘子粉末 akaganeite。

The corrosion behaviors of simulated archaeological iron in solution （0.06 mol·L^-1 NaCl＋0.03 mol·L^-1 Na2SO4＋0.01 mol·L^-1 NaHCO3） simulating soil water composition was investigated by potentialdynamic polarization, constant potential polarization, and simulated occluded cell （O.C.） galvanostatic tests. X-ray diffraction （XRD）, energy dispersive spectrometry （EDS）, and scanning electron microscope （SEM） were used to study the corrosion morphology and the evolution of corrosion product. The objective was to discover the transformation process of archaeological iron, and determine the distribution of chlorinated corrosion products. The results showed that the presence of crevice, cavities, and channels facilitates the localized corrosion under rusts; the autocatalytic effect increases the concentration of Fe^2＋, Cl^-, and SO4^2- , and promotes local acidification within the crevices and cavities. Meanwhile, the phase transformation of corrosion products is concluded to proceed by means of two ways. One is that the ferrous ions are transformed into different kinds of FeOOH via the intermediate Fe（Ⅱ）-Fe（Ⅲ） hydroxyl-salt （i.e. Green Rusts）; the other is that the Fe^2＋ ions are transformed into FeCl2, FeCl3, and orange powders akaganeite at the crevices and cavities.