Preparation and characterization of engineered stones based geopolymer composites

Abstract

The objective of the present paper is to study the effect of combination between the low liquid/solid (l/s) ratio and pressure compaction on the properties of the hardened engineered stone alkaline hybrid composites of water cooled slag/metakaolin using granite as filler and metakaolin using fine sand as filler in the ratio of 1:3, while the used activator was 5% sodium hydroxide with liquid to solid ratio of 10% to ensure low water content for better organization of the binding materials upon pressure compaction. It is well known that these combinations increase the possibility of preparing engineered stones composites with excellent engineering properties. The results showed a high dense nano- or near-nano-pore structure with high degree of homogeneity and the high strength of alkaline hardened paste compacted with low l/s ratio.The properties of the produced engineered stone alkaline hybrid composites have been studied through measurement of compressive strength, water absorption, bulk density, FTIR, petrographic examination and SEM-BSE imaging. The results exposed the possibility of forming a compact and dense composite on compacting with pressures ranging from 30 to 70 MPa.