XRD, EDX and IR analysis of solid solutions between thaumasite and ettringite

• Published in: Cement and concrete research Vol. 32; no. 5; pp. 719 - 730
• Main Authors: Barnett, S.J, Macphee, D.E, Lachowski, E.E, Crammond, N.J
• Format: Journal Article
• Language: English
• Published: New York, NY Elsevier Ltd 01.05.2002; Elsevier Science
• Subjects: Analysis of cement phases and constituents; Applied sciences; Buildings. Public works; Cement concrete constituents; Cements; EDX; Ettringite; Exact sciences and technology; Infrared spectroscopy; Materials; Properties of anhydrous and hydrated cement, test methods; Thaumasite; X-ray diffraction; X-ray diffraction; EDX; Infrared spectroscopy; Ettringite; Thaumasite; Infrared spectrometry; Transmission electron microscopy; Energy dispersion; Phase analysis; Experimental study; X ray diffraction
• ISSN: 0008-8846; 1873-3948
• DOI: 10.1016/S0008-8846(01)00750-5

Solid solutions between thaumasite and ettringite were prepared by methods analogous to those well established for the preparation of thaumasite and ettringite. The extent of immiscibility in this system is investigated by varying the Al:Si and SO 4 2−:CO 3 2− ratios in reactant mixtures. The solids produced were analysed by quantitative X-ray diffraction, with Rietveld refinement also providing accurate unit cell dimensions, energy-dispersive X-ray analysis and infrared spectroscopy. The compositional and unit cell variations in the solid solution are discussed. A wide variety of solid solution compositions were produced with both the thaumasite and ettringite structures, but all preparations were considerably diluted by secondary amorphous products.