Factors influencing the phase constitution of alite in portland cement clinker

Abstract The phase constitution of alite in portland cement clinker highly depends not only in the chemical composition of a raw mix but also on the kinetics of crystallization from the interstitial melt. From the melt of high supersaturation alite can be crystallized so quickly as to take up foreign ions in quantities in favor of the occurrence of M 3 at ambient temperature. The reverse is the case for the crystallization from the melt low in supersaturation, where M 1 tends to be formed. The formation of zoned alite can be explained by the change in the degree of supersaturation during crystallization. The phase constitution of alite can be correlated with its crystal size in terms of the supersaturation of the melt. The SO 3 in clinker considerably lowers the viscosity of the interstitial melt and thus encourages the formation of M 1 along with the grain growth of alite. The relation between the phase constitution of alite and the quality of cements has been remarked in conjunction with the Ono's method.