含氧介质中管线钢在沉积物下的腐蚀行为  

Under Deposit Corrosion Behavior of Pipeline Steel in Oxygenated Medium

作　　者：尹彦坤 贺丽敏 郑宇峰 黄一[2] YIN Yankun;HE Limin;ZHENG Yufeng;HUANG Yi(CNOOC China Co.,Ltd.,Hainan Branch,Haikou 570100,China;School of Naval Architecture and Ocean Engineering,Dalian University of Technology,Dalian 116024,China)

机构地区：[1]中海石油(中国)有限公司海南分公司,海口570100 [2]大连理工大学船舶工程学院,大连116024

出　　处：《腐蚀与防护》2022年第9期35-40,共6页Corrosion & Protection

基　　金：国家工信部高技术船舶科研项目(MC-202030-H04)。

摘　　要：采用自主设计的阵列多电极系统,研究了海砂覆盖条件下X65管线钢在含氧海水环境中的沉积物下腐蚀行为,并分析了管线钢的非均匀腐蚀过程。结果表明:海砂覆盖区的工作电极为阳极,阳极溶解产生的阳离子扩散至裸露区,导致该区域工作电极表面的pH降低,从而引发腐蚀;随着多孔腐蚀产物层的不断生成,临近海砂覆盖区的工作电极逐渐成为主要的阳极区,该区域发生严重的非均匀腐蚀;离海砂覆盖区较远的工作电极表面生成了CaCO_(3)沉淀,该沉淀层对基体起到一定的保护作用,可以使该区域的工作电极始终保持为阴极,从而使工作电极不被腐蚀。Using a self-designed array multi-electrode system,the under deposit corrosion behavior of X65 pipeline steel in oxygenated seawater environment under the condition of sea sand coverage was studied,and the non-uniform corrosion process of pipeline steel was analyzed.The results showed that the working electrode in the sea sand coverage area was the anode,and the cations generated by the dissolution of anode diffused to the bare area,which would reduce the pH of working electrode surface in this area,thereby causing corrosion.With the continuous formation of the porous corrosion product layer,the working electrode near the sea sand coverage area gradually became the main anode area,and serious non-uniform corrosion occurred in this area.CaCO_(3)precipitation formed on the surface of the working electrode farther from sea sand coverage area.The precipitation layer had a certain protective effect on the substrate,and kept the working electrode in this area as a cathode all the time,so that the working electrode was not corroded.

关 键 词：阵列多电极 沉积物下腐蚀(UDC) 非均匀腐蚀 CaCO_(3)沉淀 

分 类 号：TG172[金属学及工艺—金属表面处理]