Mechanochemical transformation of mixtures of Ca(OH)2 and (NH4)2HPO4 or P2O5

The transformations taking place during the first periods of milling are very different for both mixtures. However, prolonged milling, over nearly the same period, causes amorphization of both mixtures. DSC analysis of the milled powders showed the temperature of crystallization of hydroxyapatite and tricalcium phosphate (β-TCP). Calcinations of all the different milled powders at 800 °C for 2 h, results in the formation of hydroxyapatite and β-TCP.