Study on Processing and Characterization of Calcium Phosphate Bioceramics
The calcium phosphate bioceramics are widely used for the bone reconstruction because of their mineralogical similarities. This work aimed to obtain a biphasic calcium phosphate from hydroxyapatite nanoparticles synthesized by sonochemical technique and processed under two different conditions. The samples were uniaxially cold-pressed at 200MPa and sintered at 900°C/2h (CP900) and 1000°C/2h (CP1000) with heating rates of 2°C/min and 5°C/min, respectively. The characterizations were performed by X-ray Diffraction, Fourier Transform Infrared Spectroscopy, Scanning Electron Microscopy and theoretical elastic modulus. From the geometric method, the relative density, porosity and linear shrinkage were measured. The results showed that the studied processing conditions were useful for achieving samples formed by a biphasic calcium phosphate with 80% β-tricalcium phosphate and 20% hydroxyapatite. The CP900 and CP1000 samples presented a theoretical elastic modulus of 34.7 GPa and 53.1 GPa, respectively, which are higher than that found to the compact bone. In addition, the sintering at 900oC was sufficient to promote neck formation and particle coalescence, maintaining adequate porosity (47.5%) for bone tissue ingrowth into pores.
Aloisio Nelmo Klein, Uílame Umbelino Gomes, Nério Vicente Jr. and Dr. Henning Zoz
L. F. Cóta et al., "Study on Processing and Characterization of Calcium Phosphate Bioceramics", Materials Science Forum, Vol. 899, pp. 254-259, 2017