Preparation, fourier transform infrared characterization and mechanical properties of hydroxyapatite nanopowders

Abstract

In this work, mechanochemical method has been used to prepare nanocrystalline B-type carbonated-hydroxyapatite powder (B-CHA) using CaCO3 and CaHPO4 · 2H2O powders as raw materials with 2:3 molar ratios in air at room temperature and different ball-to-powder ratios (BPRs) ratios up to 40:1. In order to get better crystallization for the prepared CHA, all studied samples with different BPRs were sintered at 1000 °C for 2 h. Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) technique were employed to investigate both the prepared powders and sintered specimens. Moreover, microstructure as well as elemental analyses of the sintered CHA specimen was examined by scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS). Additionally, density and mechanical properties were studied also. The obtained results pointed out the formation of CHA after 4 h of milling only when the BPR = 40:1 with acceptable degree of crystallinity. Surprisingly; this milling time is not enough to prepare CHA when BPR less than 40:1 as indicated by FTIR and XRD results. These results suggested that high BPR is responsible for a significant reduction in the time of CHA preparation.