Calcium aluminates hydration in presence of amorphous SiO2 at temperatures below 90 1C
نویسندگان
چکیده
The hydration behaviour of Ca3Al2O6, Ca12Al14O33 and CaAl2O4 with added amorphous silica at 40, 65 and 90 1C has been studied for periods ranging from 1 to 31 days. In hydrated samples crystalline phases like katoite (Ca3Al2(SiO4)3 x(OH)4x) and gibbsite, Al(OH)3, were identified, likewise amorphous phases like Al(OH)x, calcium silicate hydrates, C–S–H, and calcium aluminosilicate hydrates, C–S–A–H, were identified. The stoichiometry of Ca3Al2(SiO4)3 x(OH)4x (0p3 xp0.334), which was the main crystalline product, was established by Rietveld refinement of X-ray and neutron diffraction data and by transmission electron microscopy. r 2006 Elsevier Inc. All rights reserved.
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