JOURNAL OF CERAMIC PROCESSING RESEARCH, vol.11, no.6, pp.701-715, 2010 (SCI-Expanded)
Pure and Mg2+ and F doped nano-calcium phosphates (CaP), which were synthesized by a precipitation method to investigate their microstructural and mechanical properties. After the drying and calcination processes, the samples were sintered at 1100 degrees C for 1 hour. High densities were achieved except for the 7.5% mole Mg doped samples. Due to the Mg2+ substitution, beta-TCP phase was detected besides HAp, resulting in the formation of HAp/ beta-TCP biphasic composites with different compositions. The substitutions of the ions have been verified by the decrease in the hexagonal unit cell volumes of the doped CaPs. FTIR spectra revealed the characteristic absorption bands of HAp, beta-TCP and the ones that were resulted from the F-OH bonds. In general, the microhardness and diametral tensile strength tests revealed that Mg2+ ions in large amounts (7.5% mole) had negative effects on the micro hardness of the samples, while substitution of the F- ions had a positive effect on their mechanical properties.