A Rubric for Electrochemical Testing of Metallic Biomaterials

Corrosion is a major factor for the failure of metallic medical implants. Testing a metal’s suseptability to corrosion prior to implantation is key to a successful implantation. Electrochemical processes were used in this study to evaluate the characteristics of corrosion of both AISI 316 stainless steel and titanium alloy Ti6Al4V, welded and non-welded. Linear, potentiodynamic, and cyclic polarization curves were produced by the PARC 2273 potentiostat showing the corrosion tendencies of the metals in four unique solutions 3.5% NaCl, 0.35% NaCl, phosphate buffered saline solution (PBS), and Butterfield phosphate buffered solution (BPS). The concentration of chloride ions in solutions affected the passivation current (Ipassive) and the passivation range of both AISI 316 and Ti6Al4V. In general, larger concentrations of the chloride ions increased the passivation current and decreased the passivation range. Both AISI 316 and Ti6Al4V exhibited passive behavior. Ti6Al4V proved to be the more corrosion resistant metal in the test solutions, showing the ability to repassivate and resist pitting