Biocompatibility and corrosion behavior of heat-treated Ti6Al4V-equine bone nanocomposites

Ti6Al4V-equine bone (EB) nanocomposites fabricated by powder metallurgy and heat treatment are considered attractive biomaterials owing to the combined properties of Ti6Al4V and EB, which contains natural hydroxyapatite (HAp). In this study, the biocompatibility and corrosion resistance of Ti6Al4V-EB composites were assessed by culture with MC3T3-E1 cells and corrosion tests in 0.9% NaCl solution at the normal body temperature. Biocompatibility test showed that enhanced MC3T3-E1 cell adhesion, spreading, and proliferation on the EB embed Ti6Al4V composites compared to those grown on pure Ti6Al4V. This finding is attributed to the rich HAp content of EB, which exerts a positive effect on MC3T3-E1 cell attachment to the Ti6Al4V-EB composite surface. Electrochemical analysis revealed that corrosion rate of composites containing 0.05 and 0.5 wt% EB is 0.00247–0.01132 mpy which is lower than that of pure Ti6Al4V which is 0.0358 mpy. This result indicated that the EB particles dispersed in the composite matrix interfere with the transfer of metal ions and could improve corrosion resistance. Given the excellent corrosion resistance and bioactivity of the Ti6Al4V-EB composites, these materials may have potential applications as biomaterials for implants featuring reduced healing periods without metal ion elution.