Corrosion Behavior of X70 Steel in Daqing Soils

The corrosion behavior of X70 steel in Daqing soils was studied by means of weak polarization curve technique,EIS,macroscopic observations,SEM,EDS and weight-loss method.The results revealed that localized corrosion on the X70 steel surface mainly occurred in clay,while general corrosion mainly occurred in silt.The corrosion products were primarily iron oxide which can not protect the substrate of X70 steel because of its loose structure.The corrosion rate of the steel decreased with the increasing corrosion time,and the corrosion rate in clay was much greater than that in silt.