Abstract
In this study, we prepared hydroxyapatite ceramics at 300℃ by hydrothermal hot pressing using octacalcium phosphate as the starting material. The phase and microstructure of the solidified body were determined by X-ray diffraction and scanning electron microscopy. The Vickers's hardness, bending strength and fracture toughness were measured by micro-hardness test and 3-point-bending test, respectively. The results show that c axis of hydroxyapatite crystal points to the direction normal to the load that applied during hydrothermal hot pressing. The grains are sheet and stack up to a clamshell structure along the direction the load direction. According to the microstructure, the mechanical properties of the HAp ceramics appear strong anisotropy. The bending strength and fracture toughness tested on the side normal to the load direction reach 39.6MPa and 1.34MPam^<1/2>, respectively.
