Effects of calcination and particle size on the sintering of natural hydroxyapatite

Abstract

The aim of this thesis was to investigate the best suitable method for the production of hydroxyapatite from fresh bone and to determine the effects of reducing the particle size of the hydroxyapatite powder on the microstructural properties and sintering characteristics of the final structures. For this purpose hydroxyapatite powder was obtained from fresh calf bone by deproteinization with NaOH and calcination with different processing parameters. Following this, the powders were ground by ball milling to decrease the particle size. The so produced fine hydroxyapatite powders were investigated by FTIR, X-Ray, EDAX and ESEM images and compared with each other, with ungrounded natural hydroxyapatite and with a inorganically produced, commercial hydroxyapatite. The produced hydroxyapatite powders were sintered at different times and temperatures and microstructural properties and the sintering characteristics of the final products were determined and compared with each other by EDAX analyses and ESEM images. Finally, effects of boron oxide as an additive on the sintering of hydroxyapatite were investigated.