Electrochemical Impedance Spectroscopy Analysis of 45S5 Bioglass Coating on After Oxidation of CoCrW Alloy

Abstract

Implants and prostheses, which are used to replace a missing or damaged structure in living organisms, must show all the necessary mechanical, tribological, electrochemical and biocompatibility properties together. CoCr alloys are often preferred biometals for their good mechanical strength and wear resistance, especially in dental and orthopedic implants. Although these alloys show good corrosion resistance in terms of electrochemical behavior as well as other good properties, when CoCr alloys come into contact with bone tissue, their surfaces show bioinert properties in terms of tissue formation between the implant and bone tissue. Therefore, both their corrosion behavior and biocompatibility properties need to be improved. In this study, CoCrW alloys produced by selective laser melting were coated with commercial 45S5 bioglass powder, a bioactive material, by electrophoretic deposition method. In order to improve the adhesion after coating, CoCrW alloys were subjected to electrochemical etching process during coating. After the coating process was completed, untreated, oxidized, untreated-coated and oxidized-coated samples were examined by electrochemical impedance spectroscopy (EIS) after open circuit potential measurements to investigate their corrosion behavior. As a result of the corrosion tests, it was determined that the oxidized-coated sample showed the best condition compared to the other samples in EIS analyzes.