Role of surface roughness on corrosion and fretting corrosion behaviour of commercially pure titanium in Ringer's solution for bio-implant application

摘要

Influence of roughness (r(a)) from 43 to 474nm on corrosion and fretting corrosion of commercially pure titanium (CpTi) was studied in the Ringer's solution. The anodic polarization and electrochemical impedance spectroscopy (EIS) revealed the highest corrosion resistance of CpTi with r(a) 43 nm and correlated well with the surface energy (S-E). The highest potential drop associated with the fretting corrosion is observed for CpTi with r(a) 43 nm followed by 474 nm; this is found to correspond with the worn out area. The fretting current density (i(fretting)) is several order higher than obtained during the potentiodynamic polarization (without fretting) study. Fretting corrosion manifested by the drop in electrochemical potential is simulated with high accuracy using fretting current density and an initial contact area. Fretting corrosion at an applied potential (+250 mV((sce))) is produced much larger fretting corrosion current density than during the open circuit potential (OCP). (C) 2017 Elsevier B.V. All rights reserved.