COMPARATIVE STUDY ON PRODUCTION METHODS OF POROUS HYDROXYAPATITE

Abstract

Hydroxyapatite is one of the famous calcium phosphate bioceramics. In latest years, porous HA has attracted more attention due to its low density, high porosity, high specific area, and high bioactivity. Hydroxyapatite powder was synthesized and characterized using XRD, IR, TEM, SEM and both (TGA & DTG). Fabrication of hydroxyapatite into porous samples was carried out by three different casting methods (starch consolidation, direct coagulation and freeze gel casting methods) with three different HA powder contents and fired at three different firing temperatures. Porosity, density and mechanical compression strength were measured for all porous hydroxyapatite samples. All porous hydroxyapatite samples were characterized by XRD. SEM was used to study the microstructure of some selected porous HA samples. As a result of this work, pure hydroxyapatite powder was successively prepared by wet precipitation method. The results concluded that porous HA samples prepared by freeze gel casting method showed higher mechanical strength (50.2 MPa) and thermal stability until 1200 ⁰C than those prepared by other methods.