Enhanced Surface Properties and In Vitro Corrosion Tests of Ti─Nb─Sn Coating on CoCrMo Alloy for Biomedical Applications

ABSTRACT Ti–Nb–Sn thin films were deposited onto CoCrMo alloy substrates by magnetron sputtering to enhance surface properties for biomedical applications. Structural and compositional analyses revealed a dense, crack‐free, columnar coating with a sharp interface. Potentiodynamic polarization tests in PBS demonstrated a significant improvement in corrosion resistance, with approximately 70% reduction in corrosion current density and more than 10‐fold increase in polarization resistance compared to the uncoated alloy. Wear tests under dry and PBS conditions showed that the Ti─Nb─Sn coating reduced the wear rate by more than five times, indicating enhanced wear performance. In vitro cytotoxicity assessments using MTT and LDH assays confirmed high cell viability, indicating non‐cytotoxic behavior. Overall, the Ti─Nb─Sn coating offers an effective surface modification strategy for CoCrMo‐based biomedical implants.