Influence Of Al2O3 Content On Microstructure And Properties Of Different Binary Basicity Slag Glass Ceramics

Glass-ceramic samples were prepared from a mixture that was composed of blast furnace slag, tailing and coal fly ash. FactSage software was used to calculate the batch viscosity and plot of the CaO-Al2O3-SiO2-6wt%MgO system phase diagram. The main mechanical properties, crystal morphology and crystalline phase transition of glass-ceramics were investigated as functions of batch viscosity, binary basicity (CaO/SiO2) and Al2O3 content by differential thermal analysis, X-ray diffraction, SEM-EDX and Fourier transform infrared spectroscopy techniques. Research results indicate that Al3+ cations play different roles in samples with various binary basicity values and Al2O3 contents for the formation of [AlO4] tetrahedral or (AlO6] octahedral structure, which is different from the role of Ca2+ ones. With the increase in binary basicity, the formula of high performance has a trend toward higher Al2O3 content region.