Synthesis of porous Ti–50Ta alloy by powder metallurgy

Highlights: • The proposed preview milling with the next sintering enables the homogeneous porous Ti50Ta (wt).% alloy to be obtained • The α and β nanocrystalline phases were prepared by ball milling. • For the longest sintering time there is complete diffusion of preview milled initial powders • The press and sinter route is proved to be a promising alternative for melted Ti-based biomaterials. - Abstract: The aim of the present study was to assess the possibility of producing porous Ti50Ta (wt%) alloys using powder metallurgy by characterizing the material properties. The influence of the sintering time on the microstructure, mechanical properties, and corrosion behaviour of the produced alloy was investigated. The samples were examined using scanning electron microscopy (SEM), transmission electron microscopy (TEM), optic microscopy, X-ray diffraction (XRD) and nanoindentation methods. The XRD results confirmed that nanocrystalline α and β phases were formed during high-energy ball milling. A longer sintering time of 72 h allowed complete interdiffusion of the elements in the pre-milled initial powders. The sintering time significantly influenced the microstructure and porosity. Additionally, the corrosion resistance of the Ti-Ta samples in Ringer's solution was characterized and differences were observed between the samples sintered at different temperatures. The open-circuit potential (E_OCP) and the corrosion potential (E_CORR) of all samples were similar. The sintered Ti50Ta (wt%) alloy showed better corrosion resistance than equivalent Ti or Ta reference samples. We concluded that these alloys had suitable properties for medical implant applications in the future.