Abstract: Electrochemical method， laser scanning confocal microscopy (LSCM) and scanning electron microscope(SEM) were employed to investigate the effect of the hydrochloric acid on the surface integrity of hotrolled ferritic stainless steel during pickling process. The results showed that with the increase of concentration of hydrochloric acid， the surface becomes smoother. However， high concentration results in severe intergranular corrosion. With the increase of hydrochloric acid content， the shapes of polarization curves in weak polarization area do not change obviously， but the pitting potential and the radiuses of capacitive loop increase， indicating that the corrosion resistance enhances.

Key words: ferritic stainless steel, hydrochloric acid content, pickling, polarization curve, EIS(electrochemical impedence spectrum)