Multiple Phase Identification in Alkali Activated Slag by SEM-EDS

Abstract:

Alkali-activated slag is studied using transmission electron microscopy (TEM), scanning electron microscopy (SEM), and x-ray microanalysis. Attention is focused on delineating the phases induced by the alkali activation, as these phases are important in determining the mechanical properties of the material. The starting material, slag, is found to be a heterogeneous material with at least two phases. Upon alkali activation the material becomes more heterogeneous, now exhibiting at least four phases with significant different chemical composition. Furthermore, the alkali activation is found to modify the phase rich in Ca in the unactivated slag more than the other. Alkali activation of the slag produced mostly an amorphous material with some crystalline phases such as hydrotalcite and calcite, also some nanocrystalline structures were detected by TEM.

• Periodical: Key Engineering Materials (Volume 761)
• Pages: 49-56
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.761.49
• Online since: January 2018
• Authors: Najat Alharbi, Richard Hailstone, Benjamin Varela
• Keywords: Alkali Activated Slag, SEM, TEM, X-Ray Microanalysis

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