Mechanical and corrosion characterization of industrially treated 316L stainless steel surfaces

The impact of different industrial surface treatments, such as electropolishing and micro-undulation, on the mechanical and corrosion properties of cold-rolled 316L stainless steel has been investigated. The nature of the passive layers created by the three surface finishes led not only to chemical differences as determined by XPS analysis, but also to dissimilar roughness and mechanical response as shown by surface topography and nanoindentation analysis, respectively. The industrial surface treatments appeared to improve the protective anti-corrosion properties of the stainless steel as shown by electrochemical impedance analysis. Differences in repassivation abilities were demonstrated through cyclic voltammetry and were discussed in terms of chemical profiles in the passive layer as determined from XPS. Finally, considering the passive layer as a semiconductor material, it is shown that Mott-Schottky plots are in good agreement with the chemical profile of the passive layers.