Physico-mechanical characterization of sintered glass-ceramics fabricated from iron oxide added waste soda lime glasses

This study aims to highlight the sinter-crystallization behavior and mechanical properties of the glass-ceramics prepared from modified soda lime waste glass. To this purpose, different amounts of iron oxide (Fe 2 O 3 ) (5-15 weight ratio) were added to the soda lime waste glass. The obtained mixtures were then melted and transformed into the glass-ceramics after a one-step sinter/crystallization heat treatment. According to the obtained results, wollastonite (CaO.SiO 2 ) and diopside (CaO.MgO.2SiO 2 ) precipitated in the sintered specimens, simultaneously or separately, depending on the content of iron oxide. On the basis of dilatometry analysis and the Huggins-Sun measurements, addition of iron oxide into the glass composition and its further addition increased the number of non-bridging oxygens and consequently decreased the glass viscosity. The glass-ceramics sintered at 850 °C showed the negligible water absorption and considerable content of the precipitated crystalline phases. Among them, the glass-ceramic Base-10F (containing 10 weight ratio of iron oxide) was considered as the most promising specimen due to its high mechanical strength (96 MPa), Vickers micro-hardness (491 VHN) and near zero water absorption.