国产X80管线钢的H2S应力腐蚀开裂行为

采用三点弯曲加载法，研究了国产X80管线钢及其焊接接头的抗H2S环境应力腐蚀开裂（SSCC）行为.结果表明，热影响区（HAZ）对应力腐蚀开裂最为敏感，主要是HAZ组织不均匀、晶粒粗大、硬度大，易引起局部腐蚀，从而导致该区SSCC敏感性高。母材的纵向和横向取样对H2S应力腐蚀不敏感，薄壁管材较厚壁管材有更好的H2S环境应力腐蚀抗力. 

STRESS CORROSION CRACKING BEHAVIOR OF DOMESTIC X80 PIPELINE STEEL IN H2S ENVIRONMENT

The sulfide induced stress corrosion cracking(SSCC) behavior of the weld seam and base metal of pipeline steel X80 was investigated by using the 3-point bend loading method in H2S environment.The results show that the heat-affected zone(HAZ) is the most sensitive area to stress corrosion cracking due to its high hardness and coarse grained microstructure.The rolling direction of the base metal has little influence on the SSCC behavior of the steel shows liffle angular dependence of the samples on the rolling direction of the steel plate.The SSCC resistance of the thin-wall steel tube is higher than that of the thick-wall tube.The relationship between the microstructure,mechanic properties and corrosion resistance of the welded seam was researched.