Electrochemical characterization of nitinol electrode

Metals and alloys are used as implant materials in the human body and such applications are becoming increasingly common. NiTi (Nitinol) (50%Ni, 50%Ti) is among the preferred metal alloys for biomaterials due to its biocompatibility, high processability, mechanical properties (strength) and resistance to environmental conditions. Biomaterials should be inert in terms of interaction with fluids in the human body, and since the metal alloys used may release ions, they should be selected from metals that do not cause toxic effects. In general, the liquid environments that implant materials may encounter, such as sweat, saliva, tissue fluid, etc., can cause corrosion in metallic materials, although they are not extremely aggressive. If biomaterials interact directly or indirectly with body fluids for a long time, the release of metal ions as a result of corrosion is inevitable. In this study, the corrosion behavior of NiTi alloy in different body fluids (phosphate buffered saline, Hank's artificial body fluid and Fusayama Meyer's artificial saliva solution) was investigated by electrochemical methods at 37 o C, which is considered as body temperature. The corrosion potential was monitored over time, electrochemical impedance. spectroscopy and potentiodynamic polarization technique were used. The surface properties of NiTi alloy were examined by SEM and EDS techniques. ICP-MS was used to determine whether nickel was released.