Uniformity of passive films formed on ferrite and martensite by different inorganic inhibitors

摘要

A comparison of uniformity of passive films formed on ferrite and martensite by three kinds of inorganic inhibitors, chromate, bicarbonate and nitrite, has been made by anodic polar- ization curve and AC impedance measurements. It was found, by anodic polarization curve analyses, that there was different pitting susceptibility of passive films formed on ferrite and martensite by chromate or bicarbonate. In the solution containing chloride ions, the broken potential of the passive film formed on ferrite by chromate or bicarbonate was more negative than that on martensite.