Effect of SiO2 on the Formation of Tricalcium Aluminate PDF

Keywords

lime, SiO2, stoichiometric

Abstract

The aim of the present work is to study the effect of SiO2 on the formation of tricalcium aluminate in relation to firing temperature; up to 1400 degree Celsius, as well as to determine the metastable phases in this system CaO-Al2O3_SiO2. Four mixes having the stoichiometric composition of tricalcium aluminate with 0, 0.5, 1.0 and 1.5 mole of SiO2 were studied. The compounds formed were investigated by using x-ray diffraction as well as chemical analysis to determine the phases formed and unreacted free CaO. The results showed that C3A is formed by firing the stoichiometric composition at 1400 degree Celsius for 3 hours without any additions of SiO2. Addition of SiO2 results in the formation of other phases than C3A and lower percentage of free lime