干湿交替砂土环境下X80管线钢的腐蚀行为研究  

Study on the Corrosion Behavior of X80 Pipeline Steel in Dry-Wet Alternating Sandy Soil Environment

作　　者：李丽锋 李超 罗金恒 罗立辉[4] 胥聪敏[4] LI Li-feng;LI Chao;LUO Jin-heng;LUO Li-hui;XU Cong-min(State Key Laboratory of Performance and Structural Safety for Petroleum Tubular Goods and Equipment Materials,Tubular Goods Research Center of CNPC,Xi’an 710077,China;College of Pipeline and Civil Engineering,China University of Petroleum,Qingdao 257061,China;Petrochina West Pipeline Company,Urumchi 830013,China;School of Materials Science and Engineering,Xi’an Shiyou University,Xi’an 710065,China)

机构地区：[1]中国石油集团石油管工程技术研究院,石油管材及装备材料服役行为与结构安全国家重点实验室,陕西西安710077 [2]中国石油大学(华东)储运与建筑工程学院,山东青岛257061 [3]中石油管道有限责任公司西部分公司,新疆乌鲁木齐,830013 [4]西安石油大学材料科学与工程学院,陕西西安710065

出　　处：《材料保护》2020年第3期54-60,共7页Materials Protection

基　　金：陕西省创新人才推进计划-青年科技新星项目(2018KJXX-064)资助。

摘　　要：针对管道在土壤干湿交替下的外腐蚀风险因素,采用腐蚀失重试验、电子显微分析、电化学测试等方法,研究了X80钢在砂土饱和水和干湿交替两种环境下的腐蚀行为。结果表明:X80在干湿交替土壤环境下腐蚀速率达0.33 mm/a,属极严重腐蚀,是在饱和水土壤中的2~3倍,这主要是由于在干湿交替下其腐蚀产物作为氧化剂参与反应使得阴极电流变大,加速了阳极Fe的溶解。电化学测试表明:在同等土壤腐蚀环境下,焊缝比母材更易被腐蚀,焊缝试样自腐蚀电流更高,腐蚀速率更大。For exploring the external corrosion risk factors of pipelines under alternating wet/dry soil conditions,the corrosion of X80 steel in sandy soil saturated water and alternating wet/dry environment was studied by modern methods such as corrosion weight loss test,electron microscopy analysis and electrochemical test.Results showed that the corrosion rate of X80 in dry/wet alternating soil was 0.33 mm/a,which belonged to extremely serious corrosion state,and was 2-3 times as fast as that in water-saturated soil.The serious corrosion phenomenon was mainly due to the increase of cathode current and acceleration of anode Fe dissolution,which were caused by the participation of corrosion products as oxidants in the reaction in dry/wet alternating environment.Moreover,the electrochemical tests indicated that under the same soil corrosion environment,the weld was more susceptible to corrosion than the base metal,and the self-corrosion current and corrosion rate of weld specimen were higher.

关 键 词：X80管线钢 干湿交替 土壤 腐蚀 焊缝 母材 

分 类 号：TG172.4[金属学及工艺—金属表面处理]