Characterization of Glass Ceramics Produced from Natural and Waste Raw Materials
Glass ceramics were prepared from fly ash, waste window glass and fluorite rawmaterials. Mixtures of raw materials were melted at 1300, 1400 and 1500 °C for 4 h and quenchedin cold water. The crystallization behavior of glass ceramics was investigated by differentialthermal analysis-thermogravimetry (DTA-TG). Crystallization at various temperatures (700, 800,900 and 1000 °C) for 30 min was used to obtain the glass ceramics. The obtained glass ceramicswere characterized by X-ray diffraction (XRD), light microscopy and hardness test. XRD studyrevealed that the crystallized phases were plagioclase-type minerals (diopside and albite). TheVickers hardness of the glass ceramics increased from 0.80±0.19 GPa to 6.35±0.35GPa and densityranged from 1.44 g/cm3 to 2.42 g/cm3 depending on the treatment temperature. Glass ceramicsprepared from fused glass melted at 1500 °C temperature showed the highest hardness comparedwith those melted at lower temperatures.