SVET Characterization of Localized Corrosion of Welded X70 Pipeline Steel in Acid Solution

The mophology of X70 pipeline steel weld jiont was investigated by SEM and its localized corrosion behaviors in Yingtan acid simulation solution were studied by scanning vibrating electrode technique (SVET). It is demonstrated that there was a higher corrosion current density on the surface of heat affected zone (HAZ) than on weld metal and base metal (BM). The current density of BM decreased with the increase of distance from HAZ.