Effect of residual tensile stress on stress corrosion behavior of the base metal of x80 uoe pipe

In order to investigate the role and mechanism of the residual stress on the stress corrosion behavior of the pipeline steel, SSRT test was adopted to study the stress corrosion behavior of the base metal of X80 UOE pipe with different residual tensile stress in the simulated soil solution NS4, electrochemical test techniques were adopted to test the effect of the residual stress on electrochemical polarization behavior and AC impedance characteristics of the base metal of X80 UOE pipe. It is shown that the residual tensile stress leads to the increase of the electrochemical activity and the reduction of impedance and electrochemical self-corrosion potential of the base metal surface of X80 UOE pipe, and it accelerates the nucleation and early propagation of the stress corrosion crack, which promotes the stress corrosion sensitivity of the base metal. The SCC sensitivity increases with the residual tensile stress increasing. Copyright © 2013 by the International Society of Offshore and Polar Engineers (ISOPE).