In order to analyze and test the corrosion resistance of passivation film of 316L stainless steel in electrolyte, the corrosion resistance of the 316L passivation film was detected by Tafel corrosion polarization curve, electrochemical impedance spectroscopy (EIS) and Mott - Schottky. The results of polarization curve showed that the corrosion potential was -0.955 V, and the corrosion current density was 10-4.02 A/cm2. The results of EIS indicated that when the film forming potential was 0.3 V, the corrosion resistance of the film was superior to that of the films formed under other potentials. From the Mott - Schottky analysis, it could be obtained that the donor density of the passivation film decreased roughly as the formation potential increased, whereas the thickness of the passivation film increased roughly as the increase of formation potential. Meanwhile, according to PDM analysis, the film would be corroded to a depth of 4.5 mm in 100 a under this electrolyte.
