Bio active and antibacterial oxide layers on zirconium bio materials using micro arc oxidation treatment

Titanium and Ti alloys are widely used as both orthopedic and dental implants because of their excellent mechanical properties, high corroison resistance and biocompatibility. On the other hand, zirconium belongs to same group as Ti in the periodic table and shows many similar mechanical and chemical properties to Ti has also low Young's Modulus and low magnetic susceptibility. Micro arc oxidation process is used for surface modification via electrochemical reactions. This method is similar to conventional anodization process but forms advanced coatings owing to the utilization of high voltage, current density and other process parameters. High voltage is applied to the anode in an electrolytic solution, an oxide layer start to form on the specimen surface. This is a conventional anodic oxidation process occurred above critical voltage. When this critical voltage is exceeded, micro arcs start to occur on the surface of the material. This process is defined as micro arc oxidation process. According to other coating technologies, this process shows some advantages as high layer thickness, high adhesion strength, porosity structure, low cost and friendly to the environment. In this study, the aim is to modify the surface of Zr implant material with micro-arc method. The chemical composition and structural properties of the oxide layer and the voltage dependence of the process are examined. In order to achieve an anti-bacterial oxide layer, silver acetate added to micro arc oxidation solution and examined the anti-bacterial effect of silver concentration. Antibacterial tests are performed by S. Aureus bacterias.