Electrochemical Hydrogen Charging Behaviors of High Strength Pipeline Steels

Hydrogen was charged into X70 and X80 pipeline steels in 0.5 mol/L H2SO4 solution by cathodic polarization method and the behavior of hydrogen in both steels was studied by glycerol displacement method.The results showed that a stable hydrogen concentration was obtained in the steels as the charging time was longer than 48 h at a given cathodic current density.The concentration of diffusible hydrogen in the steels was proportional to the square root of cathodic current density.The hydrogen concentration absorbed in the steels was increased with increasing the strength of the steel.