api x52钢在h2sco2饱和的nacl溶液中的腐蚀行为研究word格式论文.docxVIP

摘要通过失重法、电化学方法、U 形环实验和表面分析(SEM、EDS、XRD)技术对 API X52 钢在 H2S/CO2 饱和的 NaCl 溶液中的腐蚀行为进行了研究。研究表明：35℃时，X52 在 H2S/CO2 饱和的 5％NaCl 溶液中腐蚀速率约为 0.39mm/a，介于纯 CO2 饱和（0.29mm/a）和纯 H2S 饱和（1.4mm/a）时的腐蚀速率之 间；从 35℃到 80℃，X52 钢在 H2S/CO2 饱和的 5％NaCl 溶液中的腐蚀速率呈现出先 增加后降低的变化规律；60℃时，X52 钢在 H2S/CO2 饱和的 NaCl 溶液中的腐蚀速率 随 NaCl 浓度的增加（5%～13％）而增大。EDS 和 XRD 分析表明腐蚀产物主要为 FeS， 并有少量的 Fe(OH)2 等非晶态物质。35℃时，H2S/CO2 饱和的 5％NaCl 溶液中，裸露 X52 钢电极与有腐蚀产物膜覆盖 的 X52 钢电极偶接时，有产物膜覆盖的 X52 钢电极作为阳极发生垢下阳极溶解，其 偶接 6h 后的电偶电流密度 ia 的绝对值随裸露 X52 钢电极与有腐蚀产物膜覆盖的 X52 钢电极的面积比的增大而增加；60℃时，裸露 X52 钢电极与有腐蚀产物膜覆盖的 X52 钢电极偶接的初始阶段，有腐蚀产物膜覆盖的 X52 钢电极优先阳极溶解，但很快偶接 电极之间出现电流反转，裸露电极变为阳极而被腐蚀，其偶接 6h 后的电偶电流密度 ia 的绝对值随裸露 X52 钢电极与有腐蚀产物膜覆盖的 X52 钢电极的面积比的增大而降 低。长时间偶接后电偶电流趋近于 0，表明腐蚀产物膜与裸露金属之间的“电偶腐蚀” 不会持续存在。H2S/CO2饱和的NACE溶液（5％NaCl+ 0.5%HAc）中，在实验条件下， X52钢的 稳态渗氢电流密度随温度、H+浓度和浸没比例的增加而增大；25℃时，其应力腐蚀开 裂机理是氢致开裂型和阳极溶解型两种机制的联合作用，阳极溶解型这种机制通过氢 致开裂型起作用。关键词：X52 钢;H2S/CO2;电偶腐蚀;渗氢;U 形环AbstractThe corrosion behavior of API X52 steel in H2S/CO2 saturated NaCl solution was investigated by means of weight loss test , electrochemical measures, U-bent and surface analysis techniques, such as SEM, EDS and XRD.The results showed that in H2S/CO2 saturated 5% NaCl solution at 35℃ the corrosionrate was 0.39mm/a, which was between the rates in CO2 saturated and H2S saturated solutions at the same condition;Within the test temperature range (35℃~80℃), with temperatureincreasing, the variation of corrosion rate of API X52 took the manner as increasing firstly and then decreasing in H2S/CO2 saturated 5% NaCl solution;in H2S/CO2 saturated brine at60℃,with increasing NaCl concentration (5%~13%) the corrosion rate increased. Thecorrosion products were mainly FeS containing a small quantity of amorphous Fe(OH)2.When X52 steel was coupled with X52 steel covered corrosion product film in H2S/CO2 saturated 5% NaCl solution at 35℃, the covered one act as anodic part. Six hours later, galvanic current density increased with increasing the ratio of X52 steel to X52 steelcovered corrosion produc