A Behnamghader - Materials and Energy Research Centre (MERC), Tehran,
N Bagheri - Materials and Energy Research Centre (MERC), Tehran,
B Raissi - Materials and Energy Research Centre (MERC), Tehran,
T Forati - Department of Biomedical Engineering, Faculty of Biomaterial Science, Islamic Azad University, Science and Research Branch, Ponak, Tehran, Iran (corresponding author,

The aim of this work was to investigate the phase transformations and the sinterability of calcium pyrophosphate (CPP), prepared from a mixture of hydroxyapatite (HA) and phosphate glass. Phase and micro-structural evaluation of the sintered samples as well as physical, chemical and thermal characterization of the starting materials were performed, using inductively coupled plasma (ICP), X-ray diffraction, scanning electron microscopy (SEM), particle size measurement, simultaneous thermal analysis (STA) and density measurement. The bodies, sintered at low temperature (1000 - 1100 ºC), generated the β-CPP and α-CPP compounds, whereas at high temperature (1200 - 1250 ºC) the α-CPP phase was often identified. The reaction of the calcium methaphosphate and the HA particles appeared to be continuous and finished before the calcium methaphosphate melting.