In this work, a wedge-shaped crevice assembly simulated as
crevice corrosion was used to further understand the corrosion
behavior of pipeline steel with disbonded coatings under cathodic
protection. The changes of potential and current of steel 20#, pH
value, and oxygen content in the crevice with the simulated disbonded
coatings were measured. The effects of CP potential, crevice
thickness and the crevice corrosion behavior of steel 20# in a
simulated soil solution were investigated to elucidate the mechanism
of crevice corrosion under cathodic protections. The experimental
results could be used to improve the cathodic protection
effectiveness on pipeline steel with disbonded coatings and hence
to mitigate the pipeline corrosion in the process industries.