抄録
Hardening of α-tricalcium, tetracalcium, and amorphous calcium phosphates was examined in water and a citric acid solution. Compressive strength of hard bodies of the phosphates made in water was very weak and the highest strength was 110 kgf/cm2 of α-TCP and 30 kgf/cm2 of tetracalcium and amorphous calcium phosphates. Mixed calcium phosphate of α-tricalcium phosphate and amorphous calcium phosphate gave a hard body having a compressive strength higher than that of α-tricalcium phosphate in water and the highest compressive strength was 225 kgf/cm2. In an citric acid solution, a hard body with a compressive strength higher than in water was prepared and the highest compressive strength of α-tricalcium phosphate was 350 kgf/cm2 and that of tetracalcium phosphate was 100 kgf/cm2. The highest compressive strength of the hard bodies of α-tricalcium and tetracalcium phosphates was obtained after reaction time of 30 days and then the strength decreased with the passage of time.
