Influence of atmospheric pressure plasma treatments on the corrosion resistance of stainless steels

In this study, the influence of treatments carried out with an atmospheric pressure plasma jet (APPJ) on the passive oxide films of different types of stainless steels and their corrosion properties was studied. The treatments were realized on a martensitic (AIS1420) and a duplex (SAF2507) stainless steel using a plasma generated by air at 1.5 bar. The corrosion resistance of the samples was analyzed with potentiodynamic anodic polarization and electrochemical impedance spectroscopy tests in environments containing sulphates and/or chlorides. The effects of the treatment on the oxide layer were studied using secondary ion mass spectrometry and X-ray photoelectron spectroscopy. The plasma treatments allowed the growth of the passive film and improved the corrosion resistance of the stainless steels.