TP110SS和P110钢在酸性NaCl溶液中的腐蚀行为

Corrosion Behavior of TP110SS and P110 Steel in Acidic NaCl Solution

高含硫化氢和二氧化碳气井生产过程中油套管的腐蚀严重影响油气井安全生产。采用挂片试验和电化学技术研究了TP110SS和P110钢分别在H2S、CO2、H2S+CO2饱和的5%Na Cl溶液中的腐蚀行为,并采用扫描电镜观察腐蚀形貌。结果表明:2种钢在H2S饱和的5%Na Cl溶液中的腐蚀最为严重,在CO2饱和时的腐蚀速率最低,在H2S及H2S+CO2饱和时的腐蚀以H2S腐蚀为主,且属典型的阳极溶解型腐蚀;2种钢在H2S饱和条件下的腐蚀产物比CO2饱和条件下的腐蚀产物膜更为蓬松、多孔,与基体的结合度也较差,易脱落,局部腐蚀形貌显著。

Corrosion behavior of TP110 SS and P110 steel in 5%NaCl solution with H_2S/CO_2 was investigated by the coupon hanging tests and electrochemical techniques.Results showed that two steels were corroded the most seriously in the H_2S- saturated solution while the corrosion rate of two steels was the lowest in the CO_2-saturated solution.In the H_2S / CO_2 saturated environment,the corrosion by H_2S was more serious than that by CO_2 and the corrosion type was the typical anodic oxidation solution.Besides,the corrosion films of two steels were more fluffy and porous and easier to peel off the substrate,and the local corrosion morphology was more obvious in the H_2S- saturated solution than in the CO_2-saturated solution.