Study of Corrosion Resistance of Co-Cr-Mo Surgical Implants Alloy in Artificial Saliva

Abstract

Co-Cr-Mo alloy has been used for biomedical implant for a number of years. In this study, ASTM F-75 Cobalt-base substrate specimen was immersed in artificial saliva at 37 + 1 ºC to study the corrosion resistance properties. Surface of specimen before and after the immersion was analyzed by optical microscope and Scanning Electron Microscopy (SEM). X-Ray Diffraction (XRD) was used to study the phase structure present. The metallic ions in the artificial saliva were analyzed after the corrosion test by Absorption Spectrophotometer (AAS). Electrochemical Measurements by polarization experiments were performed to study the corrosion resistance, the main results obtained were expressed in terms of the corrosion potentials (Ecorr) and corrosion current density (icorr) in addition to measure the Tafel slops by Tafel extrapolation method, and also cyclic polarization are used in artificial saliva solution. The results of galvanic corrosion show that the Co-Cr-Mo alloy had localized corrosion in artificial saliva at 37+1ºC.