柠檬酸钝化处理对L80-13Cr不锈钢耐海洋大气腐蚀性能的影响  

Effect of Citric Acid Passivation on the Marine Atmospheric Corrosion Resistance of L80-13Cr Stainless Steel

作　　者：满宗通 牛伟乾 靳浩楠 程文佳[1] 周欢[1] 闫翔林 孙冲 林学强 孙建波 MAN Zong-tong;NIU Wei-qian;JIN Hao-nan;CHENG Wen-jia;ZHOU Huan;YAN Xiang-lin;SUN Chong;LIN Xue-qiang;SUN Jian-bo(China Oilfield Services Limited Tianjing Branch,Tianjin 300451,China;School of Materials Science and Engineering,China University of Petroleum(East China),Qingdao 266580,China)

机构地区：[1]中海油田服务股份有限公司天津分公司,天津300451 [2]中国石油大学(华东)材料科学与工程学院,山东青岛266580

出　　处：《材料保护》2022年第10期97-105,共9页Materials Protection

基　　金：中海油关键核心技术攻关项目(YSB20YF019);中央高校基本科研业务费专项资金项目(20CX06075A)资助。

摘　　要：在海洋油气开采中13Cr不锈钢常用于加工成井下工具,其在海洋大气环境储存过程中容易发生锈蚀。为了提高13Cr不锈钢在海洋大气环境中的耐蚀性能,采用单一柠檬酸和柠檬酸-氢氧化物复合钝化工艺对L80-13Cr不锈钢进行表面钝化处理,通过极化曲线、FeCl_(3)点蚀试验、中性盐雾试验、海洋大气环境户外暴露试验等研究了2种钝化处理对不锈钢耐蚀性能的影响,分析了柠檬酸钝化处理提升L80-13Cr不锈钢耐海洋大气腐蚀性能的原因。结果表明:2种柠檬酸型钝化处理均显著提高了L80-13Cr钢的抗电化学腐蚀和盐雾腐蚀性能,可以确保L80-13Cr钢在海洋大气环境中至少3个月内没有明显腐蚀。这归因于柠檬酸钝化处理显著增加了L80-13Cr钢钝化膜中Cr相关化合物的含量,提高了钝化膜的保护性。在柠檬酸钝化基础上增加氢氧化物钝化处理,有助于提高钝化膜中金属氧化物的比例,进一步增强钝化膜的稳定性和耐蚀性,使得柠檬酸-氢氧化物复合型钝化处理对L80-13Cr钢的综合防护效果优于单一柠檬酸型钝化工艺的。13 Cr stainless steel is commonly used as the material of downhole tools in the field of offshore oil & gas exploitation, but it is prone to be corroded when stored in marine atmospheric environment. In order to improve the corrosion resistance of 13 Cr stainless steel in marine atmosphere, the single citric acid passivation and citric acid-hydroxide composite passivation were selected to deal with the surface of L80-13 Cr stainless steel, and their effects on the corrosion resistance of L80-13 Cr stainless steel were investigated by polarization curve, FeCl_(3)pitting corrosion test, neutral salt spray test, outdoor exposure test in marine atmospheric environment and etc. Additionally, the reasons for the improvement of the corrosion resistance of L80-13 Cr stainless steel resulting from citric acid passivation treatment were analyzed. Results showed that the two citric acid type passivation methods could significantly improve the marine atmospheric corrosion resistance of L80-13 Cr steel and could ensure that the L80-13 Cr steel presented no obvious corrosion in marine atmospheric environment for at least 3 months. This improvement was attributed to the fact that the citric acid passivation greatly increased the content of Cr-related compounds in the passive film of L80-13 Cr steel, and thus improved the protectiveness of passive film. More importantly, the addition of hydroxide passivation treatment on the basis of citric acid passivation was helpful to improve the proportion of metal oxides in the passive film, thus further intensified the stability and corrosion resistance of passive film. Therefore, the comprehensive protection effect resulting from the citric acid-hydroxide composite passivation treatment on L80-13 Cr steel was superior to that of single citric acid passivation treatment.

关 键 词：L80-13Cr不锈钢 柠檬酸钝化 钝化膜 海洋大气腐蚀 

分 类 号：TG178[金属学及工艺—金属表面处理]