The Effect of Hydrochloric Acid Concentration on Pickling of Duplex Stainless Steel

The effect of hydrochloric acid concentration on chemical pickling of 2205 duplex stainless steel was studied with electrochemical method,weight-loss method and scanning electron microscopy(SEM).Results show that hydrochloric acid improves pickling rate,and pickling potentials of chromium depletion layer and matrix decrease with hydrochloric acid concentration.But when the hydrochloric acid concentration rises to a very high level,oxides of steel surface can′t be cleaned up,and local corrosion will occur.