Glass matrix composites from solid waste materials

Glass matrix composites have been obtained by mixing and sintering “negative cost” materials coming from municipal solid waste incinerators (MSWIs) and from one aluminium foundry. The bottom ashes from two MSWIs were used to obtain the glass matrix and the solid wastes from an aluminium alloy industry were employed as a second phase. The bottom ashes were vitrified by heating at 1400°C without any additive. The vitrification process reduces the bottom ash initial volume by about 60%. The obtained glass has a Young modulus of 96 GPa and a Vickers hardness of 6 GPa. The composites were prepared in air by a low temperature pressure-less viscous phase sintering process (740–830°C) and were morphologically and mechanically characterised. The composites showed a bending strength up to 50 MPa at room temperature and could be proposed for applications in the field of tiles.