普通13Cr钢在高温高压下的抗CO_2腐蚀性能

CO_2 Corrosion Resistance of Common 13Cr Steel under High Temperature and High Pressure

针对普通13Cr钢的CO2抗腐蚀性能,模拟大庆油田井下的腐蚀环境,通过高温高压釜进行了13Cr钢的腐蚀试验。采用SEM、EDS和XPS测试手段分析研究所获得CO2腐蚀产物膜的形貌和化学组成。结果表明,在所试验的三个温度下,13Cr钢液相、气相的腐蚀类型都主要为均匀腐蚀。其腐蚀膜的主要成分是晶态FeCO3和非晶态的Cr(OH)3,还含有少量的Fe或Cr的氧化物、碳化物和单质Fe等。在85℃和110℃下,13Cr钢的液相腐蚀速率属于中度腐蚀,基体表面形成了一层深褐色腐蚀膜层且表面平整均匀、晶粒细小、膜层较薄。在170℃下,其腐蚀速率靠近严重腐蚀的下限,接近中度腐蚀的上限。气相腐蚀与液相腐蚀腐蚀过程相似,属于中度腐蚀,腐蚀产物膜表面则为较大颗粒的晶粒,但很不规则。

The carbon dioxide corrosion experiments at high temperature and high pressure of ordinary 13Cr steel were done at the environment of DA QING oil field. The mode and chemical composition of corrosicn product films were researched by means of SEM, EDS, XPS. The results showed that under three experimental temperature, corrosion modes of 13Cr steel at liquid and gas states were all uniform corrosion. The major components of the corrosion films were crystalline FeCO3 and amorphous compound Cr （OH） 3, also included a little amount of oxide and carbide of Fe and Cr, and some pute Fe. At the temperature of 85℃ and 110℃, the corrosion rate of 13Cr steel at liquid states was mezzo corrosion. A flat puce and thin film was formed on the surface. The film was flat and uniform, crystalloid was also very thin. The corrosion rate adjoined to lower limit of serious corrosion and upper limit of mezzo corrosion at 170℃. The processes of corrosion at liquid and gas states were similar, it belonged to mezzo corrosion. The surface film of the corrosion products were big crystalloid, but anomalistic.