EELS characterisation of β-tricalcium phosphate and hydroxyapatite

Hydroxyapatite (H A) and beta-tricalcium phosphate (beta-TCP) are of great interest due to their potential I application as bone-replacement materials. h; particular, composites made of a mixture of these Ca-phosphates revealed improved mechanical properties; however, the reason for this improvement is unknown. Future development and properties enhancement Of Such bioceramics is linked to the possibility to characterise their particular microstructure. In this context, the ability to quickly identify individual grains of HA and beta-TCP within these composites will allow acquiring information about the phase distributions and the phase-boundary microstructure. The aim of the present study is, therefore, to demonstrate that electron energy-loss spectroscopy (EELS) call be successfully employed to differentiate between individual grains of HA and beta-TCP in particular, the analysis of the near-edge structure of the oxygen K-ionisation edge allows detection of a characteristic signal at ca. 536eV that call be employed as all identification tool for HA. EELS investigations were performed first oil as-received and calcined (1000 degrees C) HA and beta-TCP powders and Subsequently on pure bulk HA and beta-TCP, samples sintered at 1250 degrees C. Finally, this method was Successfully applied to a HA/beta-TCP (50/50 wt.%) composite sintered at 1250 degrees C. (c) 2005 Elsevier Ltd. All rights reserved.