Compressive and biocorrosion properties of Ti-XAl-2Fe-3Cu alloys fabricated by powder metallurgy

Abstract

Ti-XAl-2Fe-3Cu (wt%) (X = 2.7,4) alloys were fabricated by extrusion of compacts of TiH2/Al/Fe/Cu powder blends. The microstructure and compressive and biocorrosion properties of the as-extruded rods were studied and compared to those of commercial pure (CP) Ti fabricated by extrusion of a TiH2 powder compact under the same condition. The results show that the Ti-XAl-2Fe-3Cu alloy samples exhibit a significantly higher hardness and compressive yield strength than the CP Ti sample, and with increasing the Al content from 2.7 to 4 wt%, the compressive yield strength of the alloy increases from 1315 to 1422 MPa. The Ti-XAl-2Fe-3Cu alloy samples possess a better biocorrosion resistance than CP Ti, and the polarization resistance of the alloy increases with increasing Al content due to the reduced diffusion rate of corrosive ions through the surface oxide layers. Furthermore, with increasing the immersion time, the polarization resistance increases, and the double layer capacitance decreases. Overall the alloys show significantly better compressive strength and biocorrosion resistance than CP Ti, suggesting that they are more favorable than CP Ti for biomedical applications.