管线钢硫化氢应力腐蚀的影响因素

Influencing Factors of SSCC for Domestic Pipeline Steels

为了解决国产高强钢的H2S应力腐蚀开裂(sulfidestresscorrosioncracking,SSCC)敏感性问题,采用恒载荷拉伸法(constantloadtensile)和慢应变速率法(slowstrainratetest,SSRT)测试了在含H2S的介质中不同焊接匹配及不同冷变形度条件下管线钢母材及其焊接接头的SSCC性能.结果表明,不同的焊接匹配导致管线钢具有不同的耐腐蚀性能;冷变形促进了材料局部微观缺陷内能的增加,这些缺陷所在的位置往往是氢易被捕捉的地方;随着冷变形度的增加,材料的抗腐蚀能力降低.可见,焊接匹配和冷变形度是影响国产管线钢SSCC的重要因素.

With the application of domestic pipeline steel in 'Gas Transmitting from West to East' engineering, it is urgent to study sulfide stress corrosion cracking(SSCC)properties of domestic high strength pipeline steels. The constant load tensile test and slow strain rate test (SSRT) were adopted to study the effect of welding materials and cold work on the SSCC of pipeline steels in the solution with H_2S. The results suggested that different welding matches lead to different corrosive resistances of pipeline steels. A great deal of microstructure changes caused by cold work are in the state of high energy. With the increase of cold work of pipeline steels, consequently, the corrosion resistance for pipeline steels will decrease. In a word, welding match and cold work play an important role in corrosive properties of domestic high strength pipeline steels.