Effects of Fenton's Reagent on Surface Modification of Nitinol Shape Memory Alloy for Biomedical Applications

Nitinol shame memory alloy is very useful in manufacturing of medical implants and stents. Thermal oxidation and TiN coating are of common Nitinol surface modification processes and in return Fenton's oxidation using Fenton reagent is a new approach in modifying the surface of Nitinol for medical applications. To study the effects of this novel process, experimental tests including oxide surface characterization, investigation of corrosion behavior and biocompatibility of the created oxide surfaces in simulated body fluids were performed. Parameters such as temperature and duration of oxidation process were studied. Based on the results, the optimized conditions considering temperature and process duration were determined. Accordingly, Fenton's oxidation process at 65 oC for 24 hours can create an oxide surface without any cracks which produces desirable biocompatibility and corrosion resistance and helps to improve its in vivo performance.