New Processing Technique for Hydroxyapatite Ceramics by the Hydrothermal Hot-Pressing Method

A new processing technique for preparing hyroxyapatite (HAp) ceramics has been developed using the hydrothermal hot-pressing (HHP) method. Powder mixed dibasic calcium phosphate dihydrate and calcium hydroxide mixed with a Ca/P ratio of 1.67 was treated at 150°C and 40 MPa. The HHP method with the selection of the powder enabled the HAp to be solidified at the low temperature. The resulting HAp ceramics had a tensile strength of approximately 10 MPa. Furthermore, the HAp ceramics possessed a lamellar microstructure and high porosity.