管线用钢显微组织对氢致裂纹影响的研究

选用了四种不同显微组织的国产同牌号管线用钢，根据美国腐蚀工程师协会标准NACETM0284-2003，对其进行氢致开裂实验，并用光学显微镜和扫描电镜对其断面组织进行了观察，分析其显微组织对抗氢致裂纹性能的影响。认为，带状组织以及组织不均匀性是引起材料抗氢致裂纹性能下降的主要因素，但这两种因素引起开裂的方式和机理不同。同时发现晶粒度大小对该材料抗氢致裂纹性能没有明显影响。

THE EFFECT OF MICROSTRUCTURE ON HYDROGEN INDUCED CRACKING IN PIPELINE STEEL

The materials investigated in this experiment were domestic pipeline steel that have same grade.The susceptibility of four specimens to HIC were investigated according to National Association of Corrosion Engineers(NACE) TM0284-2003.Then observe the microstructures of the section using optical microscope and scanning electronic microscope(SEM).The effect of microstructures on the susceptibility to HIC of the tensile samples was evaluated referring to the primitive mechanical properties of the specimens.The results indicate that samples possessed large laths structure and that with inhomogeneous structure showed high susceptibility to HIC.But the cracking paths and the mechanisms are different.At the same time,we also find that the susceptibility of this grade of pipeline steel to HIC is irrelative with the grain size.