Hydration Reactions in the System CaO-SiO2-CaF2

The phases existing in the system CaO-SiO₂-CaF₂ were synthesized and their hydraulicity was determined. Out of these only the phase which corresponds to the formula Ca_6–0.5xSi₂O_10-xF_x exhibited distinct hydraulic properties. The hydration rate of tricalcium silicate doped with CaF₂ declined with increasing degree of doping, while its compressive strength—found at a given degree of hydration—increased. The stoichiometry and specific surface area of the formed hydrates were altered because of the presence of fluorine in the crystalline lattice.