Experimental Study of the High-Temperature Region of the Ca3(PO4)2–CaKPO4–CaNaPO4 System

An experimental study is performed of the high-temperature region of the phase diagram of the Ca3(PO4)2–CaNaPO4–CaKPO4 system. The compositions of the phase fields at 1200°C are determined. It is shown that the region of tricalcium composition at the given temperature consists of two single-phase regions: high-temperature α-Ca3(PO4)2 and low-temperature β-Ca3(PO4)2. The upper temperatures of the existence of fields of the phase triangle section at 1200°C are determined.