摘要
利用失重法、扫描电子显微镜(SEM)、X射线衍射仪(XRD)、拉曼光谱、电化学工作站等研究耐候钢在热带海洋的高温、高湿和高Cl^-大气环境中的腐蚀特征与机理。结果表明,随着暴晒时间的增加,腐蚀速率先增加后递减,在海南省海甸岛沿海岸曝晒3和6个月后,其表面被颗粒状的腐蚀产物覆盖,形成了完整的腐蚀层,但腐蚀层表面凹凸不平,多裂纹和孔隙,腐蚀产物主要为α-FeOOH,β-FeOOH,γ-FeOOH,γ-Fe_2O_3;曝晒12和24个月后,耐候钢的表面腐蚀产物变得疏松,和基体结合较弱,同时出现了蜂窝状的腐蚀特征,腐蚀产物和暴晒6个月的产物一样。随着暴晒时间的延长,腐蚀电位、腐蚀电流先增大再减小,阻抗先减小后增大,这说明耐候钢在热带海洋大气环境中的腐蚀速率先增大后减小。
Corrosion characteristics and rust layers of weathering steel Q345 field-exposed in high temperature, high humility and high Cl^- -containing marine atmosphere are investigated by mass loss method, electrochemical workstation, scanning electron microscopy, X-ray diffractometer and Raman spectroscopy. It is found that with the increasing exposure time,the corrosion rate decreased firstly and then increased, and after exposure for 3 and 6 months respectively in Haidian islet of Hainan province,the steel surface is covered by particle-like rust layer, and the rust presents cracks and pores with irregular surface. The rust composed of α-FeOOH,β-FeOOH, γ-FeOOH and γ-Fe2O3. The rust layers became dense and show up cellular shape after field-exposure for 12 and 24 months, the corrosion products are as the same as the previous one, but its adhesion to the substrate weakened. Corrspondingly, during the exposure process, the corrosion potential and corrosion current increased firstly then decreased, while the impedance decreased firstly then increased, this means that the corrosion rate of the steel increased firstly then decreased in tropical marine atmosphere.
作者
陈新彦
陈大明
陈旭
许琨
陈永
CHEN Xinyan, CHEN Daming, CHEN Xu, XU Kun, CHEN Yong(State Key Laboratory of South China Sea Marine Resource Utilization, College of Materials Science and Chemical Engineering, Hainan University, Haikou 570228, Chin)
出处
《腐蚀科学与防护技术》
CAS
CSCD
北大核心
2018年第2期150-156,共7页
Corrosion Science and Protection Technology
基金
海南省自然科学基金(20165187)~~
关键词
耐候钢
热带海洋环境
大气腐蚀
锈层
weathering steel, tropical marine environment, atmospheric corrosion, rust layer
