The rapid conversion of calcium aluminate cement hydrates, as revealed by synchrotron energy-dispersive diffraction

Abstract

The exceptional speeds of data capture available with synchrotron diffraction systems have been adapted and used to examine the structural/dynamic order of events in rapid hydration and conversion of calcium aluminate cements at high temperatures (50–90°C). The time resolution of the results obtained is sufficient to reveal effects that were not detectable or even suspected from conventional laboratory analysis. In particular, C2AH8 emerges as a ubiquitous transitionary phase, initiating the formation of C3AH6 in both the hydration and conversion processes. The dynamic diffraction data are presented and interpreted in terms of model descriptions of the order of events in high-temperature hydration and conversion.