Physical analysis and production-mechanics of glass-ceramic prototypes made by sintering cold-compacted powder samples (10% slag, 70% fly ash and 20% glass cullet)

We carried out physicochemical and mechanical characterization studies of glass-ceramic materials obtained from industrial waste of slag, fly ash and glass cullet. These studies were performed through the sintering process of powder by means of cold compaction, in concentrations of 10% slag, 70% fly ash and 20% glass cullet. A total of 230 pellets of 15 mm diameter by 5 mm thickness were produced. Later, 15 pellets were heat treated with a heating ramp of 10 ℃/min up to 1000 ℃ and held for 2 hours, followed by a cooling rate of 10 ℃/min. The remaining 15 pellets were heat treated with a heating ramp of 10 ℃/min up to 1050 ℃, followed by the same hold and cooling times. The increase in temperature favored the mechanical resistance of the glass-ceramic and the phases formed after the thermal treatments were anorthite, augite, gehlenite, and cordierite. The highest porosity found in this process was 40%; in terms of bulk densities, these were 2.36 and 2.57 g/cm³. In contrast to the observations of mechanical resistance, crystalline phases, apparent porosity, bulk density and chemical resistance. They showed that the temperature increase decreased the percentage of porosity and increased the values of densities and mechanical properties. Scanning electron microscopy images using backscattered electrons confirmed the homogenization of the mixtures in both heat treatments and mechanical properties similar to those reported for glass-ceramic materials for construction industry applications.