Effect of the Ratio SiO2/Al2O3 on the Structure, Properties, and Thermal Stability of Geopolymer Refractory Materials

Abstract

The properties of lightweight geopolymer materials (GM) based on refractory technogenic aluminosilicate wastes were studied. The effect of the ratio of the oxides SiO₂ and Al₂O₃ in the compositions of GM on the physical and mechanical properties of GM was investigated. It was found that SiO₂/Al2O₃ reduction in the GM composition results in higher density and strength and lower water absorption of the samples after a keeping period. After firing at temperatures 800 and 1000°C the strength of the samples becomes all the higher the lower the ratio SiO₂/Al₂O₃ in the composition. The heat resistance of the samples comprises four thermal cycles for high and more than seven cycles low ratio SiO₂/Al₂O₃.