Corrosion Resistance and Biocompatibility of Passivated Nitinol

Equiatomic nickel-titanium (NiTi), known as Nitinol, exhibits unique properties such as super elasticity and shape memory, which make it highly suitable for biomedical applications. The primary objective of this study is to evaluate the corrosion resistance and biocompatibility of passivated NiTi. We employed a combination of experimental assessments including corrosion tests and biocompatibility evaluations to compare NiTi with other alloys commonly used in medical implants, such as 316L stainless steel. Our findings reveal that while NiTi demonstrates superior performance in terms of mechanical properties, concerns remain regarding the high nickel content potentially leading to adverse biological reactions. Notably, we highlight the conflicting literature on the corrosion aspects of NiTi alloys and their implications for long-term use in medical devices. This study underscores the importance of understanding the complex interactions between corrosion resistance and biocompatibility in the development of implants that utilize NiTi, suggesting that further research is necessary to optimize the alloying process to enhance safety and effectiveness in clinical applications.