采用失重法测试了Q345R钢在60℃下含不同量单质硫(0,5,10,20 g/L)模拟地层水中的均匀腐蚀速率,采用扫描电子显微镜(SEM)对浸泡后的试样进行了微观形貌表征,并通过电化学方法研究了Q345R钢在含单质硫模拟地层水中的腐蚀电化学行为。结果表明:单质硫的存在加速了Q345R钢的腐蚀,随着模拟地层水中单质硫含量的增大,Q345R钢的平均腐蚀速率从0.2778 mm/a逐渐增大到1.0261 mm/a;可认为硫含量增加,降低了材料的电荷转移电阻,加速了阴极反应;同时,单质硫能引发Q345R钢的点蚀,增加局部腐蚀风险。

The uniform corrosion rate of Q345R steel in simulated formation water containing different amounts of elemental sulfur (0, 5, 10, 20 g/L) at 60 ℃ was measured by weight loss method. The microscopic morphology of the soaked sample was characterized by scanning electron microscope (SEM). The electrochemical behavior of Q345R steel in simulated formation water containing elemental sulfur was also studied by electrochemical method. The results showed that the presence of elemental sulfur accelerated the corrosion of the steel. With the increase of sulfur content in the water, the average corrosion rate of the steel gradually increased from 0.2778 mm/a to 1.0261 mm/a. It is considered that with the increase of sulfur content, the charge transfer resistance of the material was reduced and the cathodic reaction was accelerated; At the same time, elemental sulfur could cause pitting of Q345R steel and so increase localied corrosion risk.