封隔器卡瓦用20CrNiMo钢和20CrMnMo钢在某油田井下工况中的腐蚀行为  

Corrosion Behavior of 20CrNiMo steel and 20CrMnMo Steel for Packer Slips under Downhole Conditions in an Oil Field

作　　者：董社霞[1] 程文佳[1] 靳浩楠 赵煜龙 林学强 DONG Shexia;CHENG Wenjia;JIN Haonan;ZHAO Yulong;LIN Xueqiang(China Oilfield Services Limited Tianjin 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,青岛266580

出　　处：《腐蚀与防护》2024年第11期1-7,共7页Corrosion & Protection

基　　金：国家自然科学基金青年基金项目(51701240);中国石油大学(华东)校自主创新项目(17CX02023A);中海油关键核心技术攻关项目(YSB20YF019)。

摘　　要：在模拟深井/超深井的高温、高压、含CO_(2)/H_(2)S环境中,对封隔器卡瓦用20CrMnMo钢和20CrNiMo钢开展腐蚀试验;利用扫描电镜(SEM)、能谱仪(EDS)、X射线衍射(XRD)、X射线光电子能谱技术(XPS)和电化学测试等方法对比研究了两种材料的腐蚀行为。结果表明:模拟深井/超深井工况下,20CrMnMo钢腐蚀形态为典型的全面腐蚀,而20CrNiMo钢腐蚀形态为点蚀;两种材料表面形成的腐蚀产物均呈双层结构,外层腐蚀产物均由疏松絮状FeS和颗粒状FeCO_(3)构成;20CrNiMo钢内层腐蚀产物由单一的FeCO_(3)构成,而20CrMnMo钢内层腐蚀产物除了FeCO_(3)还有少量Cr(OH)_(3),Cr(OH)_(3)的存在有效提高了该钢内层腐蚀产物膜的保护性,从而使该钢耐蚀性能明显优于20CrNiMo钢。Corrosion tests were conducted on 20CrMnMo steel and 20CrNiMo steel for packer slip in the high-temperature,high-pressure and CO_(2)/H_(2)S environment simulating deep/ultra deep well conditions.The corrosion behavior of the two materials were compared and studied by means of scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS),X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS)and electrochemical testing.The results show that under the simulated deep/ultra deep well conditions,the corrosion form of 20CrMnMo steel was typical general corrosion,while the corrosion form of 20CrNiMo steel was pitting corrosion.The corrosion products on the surfaces of the two materials had a double-layer structure,and the outer corrosion products were composed of loose flocculent FeS and granular FeCO_(3).The inner corrosion product of 20CrNiMo steel was composed of FeCO_(3),while the inner corrosion product of 20CrMnMo steel had a small amount of Cr(OH)_(3)in addition to FeCO_(3).The existence of Cr(OH)_(3)could effectively improve the protection of the inner corrosion product film of 20CrMnMo steel,so that the corrosion resistance of the steel was obviously better than that of 20CrNiMo steel.

关 键 词：封隔器卡瓦 20CrNiMo钢 20CRMNMO钢 CO_(2)/H_(2)S腐蚀 腐蚀产物特征 

分 类 号：TG178[金属学及工艺—金属表面处理]