Microstructure and Porosity Evolution of the Ti-35Zr Biomedical Alloy Produced by Elemental Powder Metallurgy

Abstract

In the present study, the structure and porosity of binary Ti-35Zr (wt.%) alloy were investigated, allowing to consider powder metallurgy as a production method for new metallic materials for potential medical applications. The porous Ti-Zr alloys were obtained by milling, cold isostatic pressing and sintering. The pressure during cold isostatic pressing was a changing parameter and was respectively 250, 500, 750 and 1000 MPa. The X-ray diffraction study revealed only the alpha phase, which corresponds to the Ti-Zr phase diagram. The microstructure of the Ti-35Zr was observed by optical microscopy and scanning electron microscopy. These observations revealed that the volume fraction of the pores decreased from over 20% to about 7% with increasing pressure during the cold isostatic pressing. The microhardness measurements showed changes from 137 HV0.5 to 225 HV0.5.