Comparative Study of Biocompatible Titanium Alloys Containing Non-Toxic Elements for Orthopedic Implants

Abstract

Titanium alloys, particularly Ti6Al4V, are commonly used in biomedical applications. However, the inclusion of aluminum (Al) and vanadium (V) in this alloy can cause cytotoxic effects in the human body, resulting in Alzheimer’s disease and cancer. This study compares the performance of biocompatible alloys containing non-toxic elements, such as tin (Sn) and niobium (Nb), which are considered safe for implantation. Two sets of alloys were selected, Ti5Sn and Ti5Sn5Nb, and their properties were compared to Ti6Al4V. First, the alloys were prepared using a power metallurgical technique. Then, their phase analysis, hardness, wear resistance, strength, and corrosion performance in simulated body fluid (SBF) solution were characterized. Optical microscopy was used to study the microstructure, XRD was used to identify phases, and electrochemical testing was conducted to assess the alloys’ anodic and cathodic characteristics. Nanoindentation techniques were used to analyze surface characteristics, such as elastic modulus, nano hardness, and wear resistance. The results showed the alloys containing Nb and Sn had lower corrosion rates in SBF solution compared to Al-containing alloys. Moreover, Nb-containing alloys exhibited the highest hardness, 72% higher than Al-containing alloys. The corrosion-resistant properties of the alloys containing Nb and Sn were higher than those without Nb or Sn, suggesting they may be ideal for orthopedic implants in humans.