Microstructural investigation of geopolymer composites obtained from recyclable waste materials

Abstract

Today, researchers are exploring materials that could replace cement and provide solutions for utilizing waste products. In this study, a binder was formulated using 85% blast furnace slag and 15% fly ash. Three different additives—marble powder, strontium mineral waste, and titanium dioxide—were incorporated as partial replacements for blast furnace slag at ratios of 5%, 5%, and 1%, respectively, to create geopolymer mortars. The impact of these additives on the flexural and compressive strength of the mortars was evaluated. Furthermore, SEM/EDX analysis was performed to assess the microstructural effects of the additives. The findings revealed that titanium dioxide resulted in the highest compressive strength, recorded at 65.7 MPa. The SEM/EDX analysis suggested that the samples demonstrated a homogeneous internal structure, indicating a robust bond among the components of the matrix.

Keywords

• geopolymer
• blast furnace slag
• fly ash
• strontium
• SEM/EDX

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