Effects of shot peening on tensile properties and fatigue behavior of X80 pipeline steel in hydrogen environment

Abstract Effects of shot-peening (SP) treatment on the hydrogen embrittlement of X80 steels were investigated. The results showed SP treatment improved the HE resistance of X80 steels, which was owed to the significant concentrations of reversible and irreversible traps. However, the protective action decreased as the SP-treatment period was extended. The notch fatigue tests showed the SP treatment improves the fatigue life of X80 steels by inhibiting crack initiation. Hydrogen-accelerated crack growth governed the reduction in the fatigue life of the SP-treated specimens. At low hydrogen contents, the SP layer protected the mechanical properties of the X80 steels from hydrogen-related degradation.