Improved mechanical, bio-corrosion properties and in vitro cell responses of Ti-Fe alloys as candidate dental implants

A comprehensive study of Fe alloying influence on as-cast titanium alloys, including microstructure, mechanical properties, bio-corrosion behavior and in-vitro cell response have been carried out to evaluate the biological application potential of Ti-Fe binary alloys. The results indicate that grain sizes of as-cast Ti-Fe alloys are remarkably refined with Fe addition and the mechanical strength is increased tremendously. For instance, Ti-2Fe alloy presents excellent mechanical properties by elevating the tensile strength to 566 MPa, or 1.5 times over pure Ti, while maintaining a relative high plasticity. All Ti-Fe alloys carried in this study show a higher corrosion resistance in Hank's solution than pure Ti due to the grain refine enhancement and higher oxide film growth kinetics. Ti-2Fe alloy presents the best corrosion resistance among them and higher Fe content could bring more Fe₂O₃ to the oxidation films that decrease the corrosion resistance accordingly. All Ti-Fe alloys are holding a similar osteoblast cell viability and response to pure Ti which ensure their biocompatibility. The combination of mechanical properties, corrosion resistance and in-vitro response of Ti-2Fe promised its application as dental implants in a near future.