论文部分内容阅读
采用极化曲线、恒电位阴极极化和失重法,并结合SEM,EDS和XRD分析产物的形貌、成分和结构,研究了不同保护电位下X65碳钢的保护效果和机制。结果表明:该环境中,自腐蚀条件下的X65碳钢发生严重腐蚀,失重速率大,坑蚀严重;-800~-1000 mV的保护电位对X65碳钢的腐蚀均有明显抑制效果;-800 mV阴极保护电位下X65碳钢表面无良好的钙质沉积层形成,-900 mV下表面能生成牢固致密的钙质沉积层,有效降低保护电流密度,-1000 mV下沉积层容易因析氢反应而鼓泡脱落;相比于海洋环境,X65碳钢在油田采出水中的析氢电位偏正,沉积层中不含Mg(OH)2。
The protective effect and mechanism of X65 carbon steel under different protective potentials were studied by using polarization curves, potentiostatic cathodic polarization and weight loss methods. SEM, EDS and XRD were used to analyze the morphology, composition and structure of the products. The results show that X65 carbon steel under severe corrosion is seriously corroded in this environment, and the weight loss rate is large with severe pitting corrosion. The protective potential of -800 ~ -1000 mV can significantly reduce the corrosion of X65 carbon steel. The surface of X65 carbon steel under the cathodic protection potential of mV did not form a good calcareous deposit. Under the surface of -900 mV, a strong and dense calcareous deposit was formed, which effectively reduced the protection current density. Compared with the marine environment, X65 carbon steel has a positive hydrogen evolution potential in the produced water and no Mg (OH) 2 in the sediments.