The System Ca 3 (PO 4 ) 2 – Ca 2 SiO 4 : The Sub‐System Ca 2 SiO 4 –7 CaOP 2 O 5 2SiO 2

A study of the sub‐system Ca 2 SiO 4 –7 CaOP 2 O 5 2 SiO 2 within the system Ca 3 (PO 4 ) 2 – Ca 2 SiO 4 was conducted as a preliminary step toward obtaining new biomaterials with controlled microstructures. Phase composition of the resulting ceramics was studied using X‐ray diffraction and scanning electron microscopy with attached wavelength dispersive spectroscopy. The results showed that the sub‐system presents an invariant eutectoid point at 518°C ± 6°C with a composition of 31 wt% Ca 3 (PO 4 ) 2 and 69 wt% Ca 2 SiO 4 , and typical eutectoid microstructure of lamellae morphology. These results are in disagreement with the previous reported data, which locate the invariant eutectoid point at 500 ± 20°C with a composition of 36.75 wt% Ca 3 (PO 4 ) 2 and 63.25 wt% Ca 2 SiO 4 .