基于扫描探针技术原位研究高阻土壤中剥离涂层管道缝隙腐蚀特性及寿命预测

项目名称： 基于扫描探针技术原位研究高阻土壤中剥离涂层管道缝隙腐蚀特性及寿命预测

项目编号： No.51304259

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 矿业工程

项目作者： 王文和

作者单位： 重庆科技学院

项目金额： 25万元

中文摘要： 高阻土壤中剥离涂层管道的缝隙深处阴极保护电流难以到达以及高绝缘涂层的屏蔽作用，阴极保护效果大大降低，易使管道发生严重的缝隙腐蚀而穿孔泄漏。因此，寻求高阻土壤介质中缝隙腐蚀机理及其寿命预测方法非常必要。本项目通过设计模拟缝隙构型试验平台，采用kelvin 扫描探针等微区原位测量技术，精确原位表征涂层剥离缝隙局部空间内腐蚀电化学及传质变化规律；建立阴极保护下剥离涂层管道缝隙腐蚀动态传质过程数学模型；综合分析高度局部化缝隙空间腐蚀电化学过程表征结果，获得高阻土壤中缝隙内阴极保护机理的时空演化图，建立基于电化学模型的剥离涂层管道缝隙腐蚀寿命评价方法，并通过实例验证保护机理及预测方法的可行性。本课题的研究，旨在突出对高阻土壤中阴极保护防止剥离涂层管道缝隙腐蚀保护机理及寿命评价理论的科学认识，为管道阴极保护工程提供实验与理论依据。

中文关键词： 20#管线钢；扫描开尔文探针；局部电化学阻抗谱；缝隙腐蚀；寿命预测

英文摘要： It is difficult for cathodic protection current to reach the deep crevice gap of dissected coating pipeline in high-resistivity environment,and high insulated coating has shielding effect. The pipeline occurs serious crevice corrosion and perforation due to great reduction of the cathodic protection effect.Therefore, searching protective mechanism and control method of cathodic protection in high-resistivity environment to avoid crevice corrosion is very necessary. In this project, an expermental platform is designed by crevice geometry of artificial simulation.The change rule of the chemical and electrochemical environment in coating dissection of the gap is characterized accurately by using the scanning Kelvin probe,micro electrochemical impedance spectrum and scanning electrochemical microscope and micro zone in situ measurement techniques.And a unsteady-state mathematical model of cathodic protection dissected coating pipeline crevice is builded.Through analyzing the characterization results of chemical and electrochemical process in highly localized crevice synthetically, space-time evolution figure of protection mechanism of high-resistivity environment in a cathodically protected crevice is obtained .Moreover, this project puts forward the mechanism and control method of cathodic protection to prevent cr

英文关键词： 20# pipeline steel；Scanning Kelvin Probe（SKP）；Local Electrochemical Impedance Spectroscopy（LEIS）；Crevice corrosion；Life prediction