ZG20Mn钢在青岛海湾大桥现场大气中的腐蚀行为  

Corrosion Behavior of ZG20Mn Exposed to Atmosphere of Qingdao Bay Bridge

作　　者：杨海洋[1,2] 张波 孙丹丹 丁国清 董彩常 韩冰 YANG Haiyang;ZHANG Bo;SUN Dandan;DING Guoqing;DONG Caichang;HAN Bing(Central Iron&Steel Research Institute,Beijing 100081,China;Qingdao NCS Testing&Corrosion Protection Technology Co.Ltd.,Qingdao 266071,China)

机构地区：[1]钢铁研究总院,北京100081 [2]青岛钢研纳克检测防护技术有限公司,青岛266071

出　　处：《腐蚀与防护》2022年第1期14-17,共4页Corrosion & Protection

基　　金：国家重点研发计划(2017YFB0702303);泰山产业领军人才工程(2017TSCYCX-03)。

摘　　要：在青岛海湾大桥现场大气中对ZG20Mn钢进行了7 a的暴露试验,通过扫描电镜(SEM)、能谱仪(EDS)和X射线衍射仪(XRD)等研究了其腐蚀行为。结果表明:在青岛海湾大桥现场大气中,随着暴露时间的延长,ZG20Mn钢的腐蚀速率呈现下降的趋势,平均腐蚀深度与暴露时间符合幂函数关系;随着暴露时间的延长,ZG20Mn钢局部腐蚀的趋势增强,点蚀深度增大;MnS夹杂物和含氯盐颗粒会促进腐蚀的产生;在青岛海湾大桥现场大气中暴露7 a后,ZG20Mn钢的腐蚀产物主要为α-FeOOH、α-Fe_(2)_(3)和Fe_(3)O_(4),α-FeOOH的不断生成和沉积是造成钢大气腐蚀速率逐渐降低的主要原因,而Fe_(3)O_(4)的存在表明具有电化学活性的腐蚀产物参与了阴极去极化过程。Exposure test was carried out on ZG20 Mn steel in the atmosphere of Qingdao Bay Bridge for 7 a. The corrosion behavior of ZG20 Mn steel was studied by scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS) and X-ray diffraction(XRD). The results show that in the atmosphere of Qingdao Bay Bridge, with the increase of exposure time, the corrosion rate showed a downward trend. The relationship between average corrosion depth and exposure time conformed to a power function. With the increase of exposure time, the tendency of localized corrosion of ZG20 Mn steel increased, and the depth of pitting corrosion increased. MnS inclusions and chlorinated salt particles promoted the occurrence of corrosion. The corrosion products of ZG20 Mn steel exposed to the atmosphere of Qingdao Bay Bridge for 7 a were mainly composed of α-FeOOH, α-Fe_(2)O_(3) and Fe_(3)O_(4). The continuous generation and deposition of α-FeOOH was the main reason for the gradual decrease of corrosion rate of steel in atmosphere. The presence of Fe_(3)O_(4) indicated that the corrosion products with electro-chemical activity participated in the cathodic depolarization process.

关 键 词：大气腐蚀 暴露试验 ZG20Mn钢 

分 类 号：TG172[金属学及工艺—金属表面处理]