A new approach to combating corrosion of metallic materials

In this study a new approach that is based on creating surface patterns on metallic surfaces has been used to decrease corrosion in nickel. Patterns of holes with specific diameters (D) and inter-hole spacings (L) were created by laser ablation on nickel and potentiodynamic polarization corrosion tests were carried out in a 0.5 M H2SO4 solution. The corrosion potential, ECorr, and current density (ICorr) were determined and compared for different ratios of (D/L). Energy dispersive spectroscopy (EDS) was performed on the surface of the samples to investigate the chemical composition, specifically the oxygen content of different regions of the patterned area before and after corrosion testing. By creating such patterns we are able to produce a surface with heterogeneous wetting properties, to decrease the surface energy and to decrease the contact area between the liquid and the substrate. As a result of the surface patterning a significant improvement of corrosion properties of nickel surface has been achieved. Patterned surfaces showed better corrosion resistance compared to the polished reference samples. In addition, it has been shown that for a few specific patterns the corrosion resistance can be increased by orders of magnitude.