Mechanical properties of hydroxyapatite ceramics sintered from powders with different morphologies

In the present work, hydroxyapatite (HA) nanorods and submicron prisms were synthesized by using PVP (polyvinylpyrrolidone) and CTAB (cetyltrimethylammonium) as templates respectively, and then sintered at 1150–1250 °C. The mechanical properties of as-sintered ceramics were studied. The results show that the HA ceramics sintered from prism-like powders have a Vickers hardness of ∼5.11 GPa, a transverse rupture strength of ∼106.26 MPa, and a fracture toughness of ∼1.24 MPa m1/2, which are close to those properties of natural teeth. Moreover, it reveals that HA ceramics sintered from prism-like powders exhibit a higher density and mechanical properties than that sintered from HA nanorods, owing to the less agglomeration of raw powders and lower mass loss during the sintering process.