PSI - Issue 79

Jorge Luis González-Velázquez et al. / Procedia Structural Integrity 79 (2026) 526–533

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b)

a)

Fig. 6. Silver globules around inclusions after the HMT experiment and EDS map scan indicating the sites of hydrogen exit in a) OG and b) NG pipeline steels.

Fig. 7. Inverse pole figure (IPF), KAM: kernel average misorientation (KAM), recrystallization maps

4. Conclusions 1. The characteristics of hydrogen-induced cracking (HIC) in old generation mid-strength ferrite-pearlite (OG) and new generation high-strength martensite-bainite (NG) API 5L pipeline steels were studied. The results showed that both Old Generation and New Generation pipeline steels are susceptible to HIC, where HIC occurs by the pressure mechanism. However, the mechanical strength did not have an apparent effect on the kinetics of HIC.