P110钢在含Cl-介质中的冲刷与腐蚀行为研究

采用旋转圆盘装置并辅以电化学工作站测试P110钢在含Cl-溶液中的冲刷腐蚀行为。研究不同流速、不同含砂量对P110钢冲刷腐蚀质量损失速率和腐蚀电化学行为的影响规律,利用扫描电子显微镜(SEM)对冲刷腐蚀后试样表面进行分析表征。结果表明:P110钢在含Cl-溶液中的冲刷腐蚀形貌为典型的颗粒切削痕迹,并伴有少量腐蚀坑,冲刷腐蚀机理为机械和腐蚀相互协同作用;冲刷腐蚀过程存在一临界流速,当流速较低时主要体现为腐蚀作用,当流速超过4 m/s时材料冲刷腐蚀质量损失速率的增加主要来自于机械作用;含砂量对P110钢冲刷腐蚀起着重要影响,随含砂量增大,砂粒的机械冲刷作用增加导致冲刷腐蚀过程加剧,但过多的砂含量会形成"屏蔽作用"降低冲刷腐蚀。

Erosion and corrosion behavior of P110 steel in chloride ions solution

The erosion and corrosion behavior of P110 steel in chloride ions solution was investigated using rotating disc equipment with an electrochemical anaeysis system The effect of the main factors of fluid velocity and sand concentration on erosion-corrosion behavior was analyzed.The erosion-corrosion surface was characterized and analyzed by SEM.The results show that erosion-corrosion is controlled by the mechanical damage and corrosion process resulting from a typical ductile erosion damage involving a few pits.There exists a critical velocity(4 m/s),the erosion-corrosion process is dominated by corrosion effect when velocity is less than 4 m/s.When the velocity is larger than 4 m/s,the mechanical effect contributes to the erosion-corrosion process.The sand concentration shows great influence on the erosion-corrosion of P110 steel.The erosion-corrosion process is accelerated by the sand concentration,while the excessive sand can lead to the decreasing of erosion-corrosion process for the "shielding effect".