温度对X65和3%Cr管线钢CO_2腐蚀行为的影响

Effect of Temperature on CO_2 Corrosion Behaviors of X65 and 3% Cr Pipeline Steels

利用高温高压反应釜对X65及新研制开发抗CO2腐蚀的含3%Cr低合金管线钢在不同温度下的CO2腐蚀行为进行研究。结果表明,X65管线钢腐蚀速率随温度升高呈先增大后减小的规律,在80℃附近达极大值,含3%Cr低合金管线钢的腐蚀速率随温度升高呈单调增加趋势。X65管线钢腐蚀产物膜以FeCO3晶体堆垛为主要特征,含3%Cr低合金管线钢腐蚀产物膜主要由FeCO3和Cr(OH)3组成,随温度升高腐蚀产物中的Cr含量显著提高,Fe含量明显下降。含3%Cr低合金管线钢表面形成的富Cr腐蚀产物膜结构致密无孔洞,显著降低均匀腐蚀速率和有效抑制局部腐蚀发生。

The CO2 corrosion behavior of X65 and 3% Cr containing low alloy pipeline steel,which had been researched and developed for CO2 corrosion resistance recently,was observed by high-pressure high-temperature autoclave.The results show that,the corrosion rate of X65 pipeline steel increased at first then decreased with the temperature increasing,which reached the maximum at 80 ℃.However,the corrosion rate of 3% Cr containing low alloy pipeline steel monotonously increased with the temperature increasing.The corrosion product scale of X65 pipeline steel was crystal,which composition was FeCO3.While the corrosion product scale of 3Cr low alloy pipeline steel composed mainly of FeCO3 and Cr(OH)3,and whose Cr content increased and the Fe content decreased with the temperature increasing.The Cr enrichment corrosion product scale without holes was compact,which played an important role of reducing corrosion rate and inhibiting localized corrosion effectively.