The role of surface roughness during fretting corrosion of 316L stainless steel

Fretting corrosion is a synergistic process between the mechanical events and the chemical attack of two contacted surfaces for similar or different alloys. Since implant devices are designed to slide or rotate to perform their function, implant devices may subject to mechanical interaction such as friction, wear damage, together with a corrosive attack as it in contact with human body fluids. The current study focuses on assessing the fretting corrosion resistance of 316L stainless steel (SS) under several applied load (0.5-10) N and grinded surface (400, 600, and mirror finish) grit. The experiment was performed by using a pin on disc technique surrounded by 25 degrees C Phosphate buffer saline. The morphology, elemental analysis, and resistance to fretting corrosion are investigated by using scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS) as well as the Tafel extrapolation method. The results demonstrate that the mirror surface finish gives a lower average fretting corrosion current density value with less debris generation as compared with rougher surface (400 and 600) grit. However, when a high load is applied, the current density seems to be struggling in recovering to the baseline due to the initiation of localized corrosion. The SEM scan clarified the arising of fretting islands. The EDS analysis indicated a high accumulation of chromium and oxygen elements on the fretted area border as compared to the center. (C) 2021 Elsevier Ltd. All rights reserved.