Cytocompatible tantalum films on Ti6Al4V substrate by filtered cathodic vacuum arc deposition

Tantalum films were deposited on negatively biased Ti6Al4V substrates using filtered cathodic vacuum arc deposition to enhance the corrosion resistance of the Ti6Al4V alloy. The effect of substrate voltage bias on the microstructure, mechanical and corrosion properties was examined and the cytocompatibility of the deposited films was verified with mammalian cell culturing. The Ta films deposited with substrate bias of -100V and -200V show a mixture of predominantly β phase and minority of α phase. The Ta/-100V film shows adhesive failure at the Ti/Ta interface and a cohesive fracture is observed in Ta/-200V film. The Ta/-100V showed a significant improvement in corrosion resistance, which is attributed to the stable oxide layer. The in-vitro cytocompatibility of the materials was investigated using rat bone mesenchymal stem cells, and the results show that the Ta films have no adverse effect on mammalian cell adhesion and spreading proliferation.