摘要
采用四点弯曲试验,研究拉应力对油井管抗SSCC性能的影响,加载比例分别为0、50%、80%和90%,利用OM、LCSM、EPMA等分析手段研究加载比例对油井管试样的微观腐蚀形貌和腐蚀深度的影响,分析锈层横截面形貌和元素分布情况。结果表明:油井管的金相组织为回火索氏体;弯曲加载使点状腐蚀坑沿垂直于拉应力的方向扩展,由点状逐渐变成长条状,随着加载比例的增加,腐蚀坑的长度和深度逐渐增加,相邻的点蚀坑聚集形成更大的腐蚀坑,应力腐蚀敏感性增强;Cr和Mo促使锈层致密,阻碍H原子的扩散和S离子迁移,提高了抗应力腐蚀性能。
The influence of bending loads of 0, 50%, 80% and 90% of the yield strength of the test material respectively on the corrosion morphology and corrosion depth of oil-well tubes was investigated by means of OM, LCSM, EPMA et al. The result showed that the oil-well tubes presented a microstructure of tempered sorbite. With the increasing bending load, the pitting corrosion extends perpendicular to the pulling stress, the pitting corrosion turned to be strip-like gradually. The pits contiguous gathered together into huge ones as the degree of corrosion aggravated, which enhanced the stress corrosion susceptibility. It was revealed that the presence of Cr and Mo made rust layer denser, which could prevent the inward migration of H and S, therewith improved the anti-stress corrosion property of the oil-well tubes.
作者
钟彬
陈义庆
艾芳芳
高鹏
李琳
孟凡磊
伞宏宇
ZHONG Bin;CHEN Yiqing;AI Fangfang;GAO Peng;LI Lin;MENG Fanlei;SAN Hongyu(State Key Laboratory of Metal Material for Marine Equipment and Application,An-shan Iron & Steel Institute,Anshan 114009,China;An-shan Iron & Steel Group Corporation,Anshan 114006,China)
出处
《腐蚀科学与防护技术》
CAS
CSCD
北大核心
2019年第5期526-530,共5页
Corrosion Science and Protection Technology
关键词
油井管
微观组织
弯曲加载
应力腐蚀
oil-well tube
microstructure
bending load
stress corrosion
