Q235碳钢在四川典型大气污染环境中的腐蚀行为研究

Study on corrosion behavior of Q235 carbon steel in typical atmospheric pollution environment in Leshan,Sichuan province

基于目前电网输变电设备腐蚀严重的实际情况,选取四川省乐山市城市、化工工业及陶瓷工业三种典型大气污染环境,通过1年期的暴露试验对Q235碳钢材料的大气腐蚀行为进行研究.利用失重法测定了Q235碳钢材料在不同环境下的大气腐蚀速率以及大气腐蚀等级.通过宏观形貌、扫描电子显微镜(SEM)、能谱分析(EDS)、X射线衍射(XRD)、电化学测试等方法深入研究了Q235碳钢材料在四川乐山不同大气污染环境中的腐蚀行为.结果表明,四川乐山不同大气环境对Q235碳钢的腐蚀影响由重到轻依次为陶瓷工业环境、化工工业环境及城市环境.腐蚀速率越高,腐蚀产物颜色越深且越致密,尖锐程度越突出;腐蚀产物主要成分均为α-FeOOH、γ-FeOOH和Fe3O4;Q235碳钢表面的锈层不具有保护基体的作用,反而会加快基体的腐蚀.

Based on the severe corrosion of power transmission and transformation equipment in the power grid,three typical atmospheric pollution environments were selected to study the atmospheric corrosion behavior of Q235 carbon steel material by one-year exposure test,including Leshan city,chemical industry and ceramic industry in Sichuan province.The atmospheric corrosion rates and atmospheric corrosion grades of Q235 carbon steel in different environments were measured by weight-loss method.The corrosion behavior of Q235 carbon steel in Leshan was studied by means of macroscopic morphology,scanning electron microscope(SEM),energy spectrum analysis(EDS),X-ray diffraction(XRD)and electrochemical test.The results showed that the corrosion effect of Q235 carbon steel in Leshan was different.Ceramic industrial environment had the highest effect,followed by chemical industrial environment and the urban environment.The higher the corrosion rate is,the darker and denser the color of the corrosion products,and the more prominent of the sharpness.The main components of the corrosion products wereα-FeOOH,γ-FeOOH and Fe3O4.The rust layer on the surface of Q235 carbon steel did not protect the matrix;on the contrary,it accelerated the corrosion of the matrix.