Hydrogen Permeation and Electrochemical Corrosion Behavior of the X80 Pipeline Steel Weld

In this work, the microstructure of an X80 pipeline steel weld was characterized by optical and scanning electron microscopy. The hydrogen permeation and electrochemical corrosion behavior were investigated by various electrochemical measurements and analysis. It was found that there is the smallest hydrogen permeation rate, but the largest hydrogen trapping density at heat-affected zone, while the base steel has the lowest hydrogen trapping. These results are associated with the typical microstructure of the individual zone. Moreover, the accumulation of hydrogen atoms would result in an enhanced corrosion locally.