Effect of elastic stress and alternating current on corrosion of X80 pipeline steel in simulated soil solution

摘要

Effects of elastic stress and alternating current (AC) on corrosion behavior of X80 pipeline steel were investigated in a simulated soil solution by electrochemical techniques and surface analysis. Corrosion current density was 40.5 mu A/cm(2) by synergistic effects of the stress and the AC current, being about five times of that without the stress and the AC current. Corrosion morphology of the steel coupon was pitting corrosion with application of AC current, and changed from pitting corrosion to moat corrosion under effects of the stress and the AC current. Corrosion of the steel coupon was enhanced by increasing anodic dissolution of iron and porosity of corrosion product film.