交直流杂散电流与应力耦合作用下高强钢管线腐蚀与涂层剥离的非稳态电化学理论与分析方法研究

项目名称： 交直流杂散电流与应力耦合作用下高强钢管线腐蚀与涂层剥离的非稳态电化学理论与分析方法研究

项目编号： No.51471011

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 一般工业技术

项目作者： 王新华

作者单位： 北京工业大学

项目金额： 85万元

中文摘要： 随着输送压力的不断提高以及各种交直流杂散电流的侵扰，埋地高强钢管线的运行环境更趋复杂，给埋地高强钢管线的安全运行与腐蚀防护提出了新的要求。项目以X70、X80、X100高强钢管线和涂覆石油沥青、三层PE的埋地钢质管道为研究对象，针对应力与交直流杂散电流耦合作用下高强钢管线的腐蚀与涂层剥离新问题，以电化学理论为基础，并融合材料学、力学、电磁学、化学、金属腐蚀学、热力学等多学科理论，在理论分析与实验研究基础上，通过采用多物理场数值计算方法以及先进的电化学测试与表面分析技术，系统研究应力作用下交直流杂散电流在埋地高强钢管线内的传播特性与传播规律，研究交直流杂散电流与应力耦合作用下埋地高强钢管线的腐蚀机理与腐蚀特性以及涂层剥离机理与剥离特性，并建立相应的危害性评价技术与方法，形成系统开展交直流杂散电流与应力耦合作用下高强钢管线腐蚀与涂层剥离研究的电化学基础理论与方法。

中文关键词： 杂散电流；应力；高强钢管线；涂层剥离；电化学腐蚀

英文摘要： With the increase of operating pressure and the interference of alternating current/direct current (AC/DC) stray current, the operating environment of buried high-strength steel pipeline is becoming more complex, which proposes new requirement for safety running and corrosion protection of buried high-strength steel pipeline. In this project, high-strength steel (X70, X80, X100) pipelines without coating, asphalt-coated steel pipeline and three-layer polyethylene-coated(3PE) steel pipeline are objects researched. For the cathodic disbonding and coating defects where the problem of the disbonded coating caused by stray current flowing and the point of layers under corrosion with corrosions on defects resulted fom the disbonded coating, based on the electrochemical theory, the multidisciplinary cross research thought and the oretical analysis and experimental research, besides, the integration of material science, mechanics, electromagnetism and fusion, chemical, metal corrosion, thermodynamics and other multi-disciplinary theory, by adopting multi-physics coupling numerical method, advanced electrochemical measurement technique and surface characterisation technique, the non-steady-state electrochemical process of disbonded coating and corrosion of high-strength steel beneath coupling effect of stress and AC/DC stray current are studied, finally, the corrosion mechanism and release properties, disbonded coating mechanism and release properties of high-strength steel are revealled fully. Its research contents mainly include: the propagation characteristics and propagation law of AC/DC stray current in buried high-strength steel pipeline beneath stress; the non-steady-state electrochemical process and mechanism of disbonded coating for high-strength steel pipeline under coupling effect of stress and AC/DC stray current; the non-steady-state electrochemical process and mechanism of corrosion of high-strength steel pipeline under coupling effect of stress and AC/DC stray current; the establishment of dynamic mathematical model and the research on electrochemical behavior of high-strength steel pipeline beneath the interaction between disbonded coating and corrosion, while the pipeline suffered coupling effect of stress and AC/DC stray current; corrosion law and properties experiment of high-strength steel pipeline under coupling effect of stress and AC/DC stray current, the establishment of corrosion rate mathematical mode and the research on evaluation method of corrosive hazardous of high-strength steel pipeline under coupling effect of stress and AC/DC stray current. Through this study, the essential characteristics and electrochemical protection technology for corrosion beneath coupling effect of mechanical and electrochemical are revealed by establishing the electrochemical basic theory and method of analyzing corrosion of high-strength steel pipeline under coupling effect of stress and AC/DC stray current.

英文关键词： stray current;stress;high-strength steel pipeline;coating stripping;electrochemical corrosion