The Manufacturing of Titanium-Hydroxyapatite Nanocomposites for Bone Implant Applications

Abstract

Hydroxyapatite (HA, Ca 10 (PO 4 ) 6 (OH) 2 ) shows excellent biocompatibility, so it can be the most suitable ceramic material for hard tissue replacement implants. On the other hand, due to its low mechanical properties, HA cannot be used for heavy applications. The combination of good biocompatibility of hydroxyapatite and excellent mechanical properties of titanium is a good candidate way to expand the biomedical applications. The aim of this study was to develop new titanium-hydroxyapatite nanocomposites for biomedical applications. Bulk nanocomposites with different HA contents were successfully prepared by the combination of mechanical alloying (MA) and powder metallurgical process. The structure, mechanical and corrosion properties of these materials were investigated. The results show an enhancement of properties due to the nanoscale structures in bulk consolidated materials. For example, Vickers' hardness of Ti-10 vol% HA composite is higher than of pure microcrystalline Ti metal (250 HV) and reaches 1300 HV. On the other hand, the Ti-10 vol% HA composite is more corrosion resistant ( Ic = 1.1×10 -6 , Ec = -0.48) than the microcrystalline titanium ( Ic = 2.7×10 -5 , Ec = -0.47). Titanium-hydroxyapatite bulk structures are promising biomaterials for the use as replacement implants.