不锈钢在含有溴离子的醋酸溶液中的腐蚀

采用浸泡试验及电化学试验，对304、254 SMO和HastelloyC－276三种材料在醋酸和含有Br^-离子的醋酸溶液中的腐蚀行为进行了测试。用SEM和XPS分析点蚀形貌。结果发现材料表面所形成的钝化膜中含有Cr2O3和MoO2，对材料起保护作用。

CORROSION BEHAVIOR OF 304, 2S4 SMO AND Hastelloy C-276 IN HAc SOLUTION CONTAINING Br- ION

Uniform corrosion and pitting corrosion behavior of stainless steel and high-nickel alloys in acetic acid solution containing Br - ion have been investigated. Immersion test method was used to measure general corrosion rate and potentiodynamic cyclic polarization was used to study pitting corrosion behavior. The tested results found that the material of 304 experienced serious general corrosion, the next was 254 SMO and the uniform corrosion rate of Hastelloy C-276 was the least. The addition of Br - ion into the solution fastened the uniform corrosion rate of these materials. In addition, Hastelloy C-276 had a good performance of resisting pitting, the next was 254 SMO and 304 experienced serious pitting attack. Micrographs of pits produced after anodical polarization were observed by SEM. The elements of the surface passivity film were inspected by XPS, whose results indicated that the elements of Cr and Mo played an important role in resisting corrosion. EPMA results indicated that Si, S and O elements existed in the pits, which means that sulfide inclusions were the sites initiating pitting.