摘要
目前,对管线钢在外加电位下的应力腐蚀开裂的研究尚不全面。应用慢应变速率拉伸、扫描电镜(SEM)观察和动电位极化测试方法,研究了在近中性模拟土壤溶液(NS4)中,不同阴极保护电位下X80管线钢的应力腐蚀开裂(SCC)行为。结果表明:X80管线钢的SCC行为与阴极保护电位密切相关;在-850,-1 000,-1 200 m V(相对饱和硫酸铜电极)3个保护电位下,阴极过程析氢反应起主要作用,随着阴极保护电位的负移,X80管线钢的脆性逐渐增大;在-1 200 m V条件下SCC敏感性系数最高,形变硬化指数最低,SCC现象最为严重。
The stress corrosion cracking( SCC) behavior of X80 pipeline steel under different cathodic protection potential in near neutral simulated solution of soil was investigated by slow strain rate test and potentiodynamic polarization curve measurement in association with scanning electron microscopic observation. It was found that the SCC behavior of the X80 pipeline steel was closely related to the cathodic protection potential. Namely, under cathodic protection potentials of- 850,- 1 000,- 1 200 m V,hydrogen evolution process was dominant in the cathodic reaction;and the brittleness of the pipeline steel tended to gradually increase with the negative shift of the cathodic protection potential.Particularly,under the cathodic protection potential of- 1 200 m V,the X80 pipeline steel exhibited the maximum SCC sensitivity coefficient and the lowest strain hardening index as well as the most severe stress corrosion cracking.
出处
《材料保护》
CAS
CSCD
北大核心
2015年第5期42-45,52,共5页
Materials Protection
