X70管线钢.docx

Effect of Environmental Factors on Electrochemical Behavior ofX70 Pipeline Steel in Simulated Soil Solution在模拟土壤溶液中环境因素对X70管线钢电化学行为的影响ZHANG Liang, LI Xiao-gang, DU Cui-wei(School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China)Abstract:Potentiodynamic polarization measurement was used to investigate the effects of temperature, dissolved ox-ygen concentration and pH on the electrochemical behavior of X70 pipeline steel in simulated solution according to theorthogonal testing method. 根据正交试验法，利用动电位极化测量来研究温度、溶解氧浓度和pH值对X70管线钢在模拟溶液中的电化学行为的影响The results showed that temperature, dissolved oxygen concentration and pH had greatinfluence on corrosion current density (icorr) of X70 steel. Corrosion current density of X70 steel was most influencedby dissolved oxygen concentration in simulated solution. The corrosion degree of X70 steel was the least under theenvironment of low temperature, deficient oxygen and weak acid.结果表明温度、溶解氧浓度和pH值对X70钢的腐蚀电流密度有很大的影响，其中影响最大的是模拟溶液中的溶解氧浓度。在低温、缺氧和弱酸环境下，X70钢的腐蚀程度最小。Key words:X70 pipeline steel; potentiodynamic polarization measurement; orthogonal testing; corrosion currentDensity关键词：X70管线钢；动电位极化测量；正交试验法；腐蚀电流密度 The Chinese West-East Natural Gas Transmis-sion Project with investment of 15 billion USD mainlyuses X70 pipeline steel. With pipeline of 4 000 km inlength, the project crosses lots of areas, and passesthe salty soil area. The Kucerle soil is one of typicaltypes of wilderness salty soil in western China. The soilsolution was assumed alkaline, and the salt contentwas high[1]. Hence, the pipeline steels were easy toinduce pitting corrosion, and initiated the stress cor-rosion to failure. Therefore, the studies of environ-mental factors on corrosion behavior of X70 steelhave a vital practical significance.中国耗资150亿美元的西气东输工程就主要采用了X70管线钢。该项目长达4000千米的管道跨越多个区域，途径盐渍土地。库尔勒区土壤溶液为碱性，盐含量很高，是中国西部荒漠盐渍土的典型代表之一。此种情况下，管线钢很易出现点状腐蚀和应力腐蚀而导致工程功亏一篑。因此研究环境因素对X70钢腐蚀行为具有重要的现实意义。Some investigations have been