Q235碳钢在红壤中的腐蚀行为  

Corrosion Behavior of Q235 Carbon Steel in Red Soil

作　　者：裴锋[1] 田野[2] 刘平[1] 田旭[1] 

机构地区：[1]国网江西省电力科学研究院,南昌330096 [2]长沙理工大学化学与生物工程学院,长沙410014

出　　处：《腐蚀与防护》2016年第9期715-719,共5页Corrosion & Protection

基　　金：江西省变电站接地网腐蚀性评价方法研究项目(201250606)

摘　　要：采用扫描电镜(SEM)、能谱(EDS)和X射线衍射(XRD)等技术对在红壤中服役多年的变电站接地网Q235碳钢进行了形貌观察和腐蚀产物分析,并通过电化学和模拟加速腐蚀试验对比研究了Q235碳钢在红壤中的腐蚀行为。结果表明:接地网材料表面形成的腐蚀产物主要是铁的氧化物,主要有Fe2O3、Fe3O4、FeOOH,并且Cl元素的存在会加剧Q235碳钢材料的腐蚀;当土壤含水率为20%(质量分数,下同)时,Q235碳钢在红壤中腐蚀速率最大,Q235碳钢的腐蚀电流密度随Cl-与SO42-的变化规律基本一致,都是先增大后减小,并且可划分为3个区间;Q235碳钢在红壤中的腐蚀速率随着试验时间的延长呈现先降低后小幅升高的趋势,该加速腐蚀试验,没有改变Q235碳钢在红壤中的腐蚀机理,且与现场有较好的相关性。Morphology and corrosion product of Q235 carbon steel used for many years in substation grounding grid in red soil were studied by scanning electron microscopy （SEM）, energy dispersive spectroscopy （EDS） and X-ray diffraction （XRD）. The results show that corrosion products on the grounding grid surface were mainly composed of iron oxides including Fe2O3, Fe3O4, FeOOH. And the existence of Cl^- could accelerate the corrosion of Q235 carbon steel. The largest corrosion rate of Q235 carbon steel was achieved when the water content was wt20%, and the corrosion current density of Q235 carbon steel had same tendency with the increase of content of Cl^- and SO4^2- , showing increase first and then decrease, and it can be divided into three intervals. The corrosion rate of Q235 carbon steel in red soil presented the tendency of first decrease and then increase in small range with the increase of experimental time. The corrosion mechanism of Q235 carbon steel in red soil did not change in the accelerated corrosion experiment which had a good correlation with the corrosion in worksite.

关 键 词：接地网 Q235碳钢 红壤 电化学.力口速腐蚀 

分 类 号：TG172.4[金属学及工艺—金属表面处理]