摘要
目前涉及到3个及以上风险因素的管线钢应力腐蚀研究还较少。为此,通过混合水平的正交试验法,采用慢拉伸试验研究了钢级、保护电位、温度、土壤环境等各敏感因素对高钢级管线钢应力腐蚀开裂行为的影响权重,并采用扫描电镜(SEM)观察了-1500 mV(vs CSE)保护电位下高钢级管线钢在近中性和高pH值模拟土壤溶液中的应力腐蚀行为。研究结果表明:管线钢外部应力腐蚀开裂风险在设置的试验水平因素中,保护电位对应力腐蚀指数ISSRT影响的权重最大,随后依次是温度、钢级及土壤环境;保护电位-1500 m V下,X70、X80管线钢在近中性和高p H值模拟土壤溶液中均具有较强的应力腐蚀敏感性,其SCC机制均为氢脆(HE)机制。
Nowadays,the researches on more than 3 risk factors which influenced stress corrosion cracking of pipeline steel have less been studied.In this work,the influence weights of various sensitive factors such as steel grade,protection potential,temperature and soil environment on the stress corrosion cracking(SCC)behaviors of high-grade pipeline steel were studied by means of orthogonal test at mixed level and slow strain rate test.Moreover,the stress corrosion behaviors of pipeline steels in simulated soil solution with near-neutral and high p H values under over-protection potential of-1500 m V were observed by scanning electron microscope(SEM).Results showed that among the experimental risk factors which influenced the external stress corrosion cracking of pipeline steel,the protection potential had the maximum weight in the stress corrosion index of ISSRT,followed by temperature,steel grade and soil environment.Under over-protection potential of-1500 m V,both X70 and X80 pipeline steel exhibited high stress corrosion sensitivity in simulated soil solutions with near-neutral and high p H values,and the SCC mechanism belonged to hydrogen embrittlement(HE).
作者
伍奕
朱丽霞
贾海东
罗金恒
徐春燕
武刚
许光达
WU Yi;ZHU Li-xia;JIA Hai-dong;LUO Jin-heng;XU Chun-yan;WU Gang;XU Guang-da(CNPC West Pipeline Company,Urumchi 830013,China;CNPC Tubular Goods Research Institute,Xi'an 710077,China;CNPC Key Laboratory for CNPC Tubular Goods Engineering,Xi'an 710077,China)
出处
《材料保护》
CAS
CSCD
北大核心
2020年第5期47-52,共6页
Materials Protection
关键词
管线钢
应力腐蚀开裂
风险因素
权重
保护电位
pipeline steel
stress corrosion cracking(SCC)
risk factor
weight
protection potential