论文部分内容阅读
采用电化学阻抗、丝束电极、SEM/EDS和XRD的分析方法,研究原油沉积水对Q235B碳钢腐蚀行为的影响。结果表明,碳钢在沉积水中浸泡21 d过程中,腐蚀速率逐渐降低,腐蚀形式以均匀腐蚀为主;而从21~35 d浸泡过程中,碳钢的腐蚀速率逐渐增大,且腐蚀程度加剧,腐蚀形态由均匀腐蚀为主转变为以点蚀为主的局部腐蚀,点蚀的大小和密集度增加。这是由于在起始阶段,碳钢表面沉积一层CaCO_3,有效地阻碍了腐蚀,而随着时间的延长,CaCO_3逐渐失去对碳钢基体的保护,从而加速局部腐蚀的发生。
The effects of crude oil deposition on the corrosion behavior of Q235B carbon steel were studied by electrochemical impedance spectroscopy, wire electrode, SEM / EDS and XRD. The results show that the corrosion rate of carbon steel decreases with the immersion time of 21 days in sedimentary water, and the corrosion forms are mainly uniform. From 21 to 35 days, the corrosion rate of carbon steel gradually increases and the corrosion degree is aggravated , The corrosion morphology changed from uniform corrosion to pitting-based local corrosion, and the size and concentration of pitting increased. This is because in the initial stage, the deposition of a layer of CaCO 3 on the surface of carbon steel effectively hindered the corrosion. With the extension of time, CaCO 3 gradually loses the protection of the carbon steel matrix and accelerates the local corrosion.