Corrosion Study and Surface Analysis of the Passivation Film on Surface-Deformed AISI 304 Stainless Steel

The surface analysis of the passivation film formed on surface-deformed AISI 304 stainless steel was carried out in the present study, and its corrosion properties were also determined. The morphology of the surface layer and the phase identification before and after surface modification was examined via scanning electron microscope (SEM) and X-ray diffraction (XRD) techniques, respectively. The composition of the resulting passive film as well as Cr distribution as a function of sputter depth was characterized by X-ray photoelectron spectroscopy (XPS) method. The XPS spectra revealed the existence of Cr, Fe, O, Ni, and C as the principal elements in the resulting passive films formed on the treated 304 steel sample with a high percentage of Cr at the top surface layer. Compared to the untreated sample, the potentiodynamic polarization tests revealed that the treated sample exhibited a better corrosion behavior in terms of higher corrosion potential, lower corrosion current density, and higher impedance.