Development and mechanical characterization of Al2O3 platelet-reinforced glass matrix composites obtained from glasses coming from dismantled cathode ray tubes

A cold-pressing and pressure-less viscous flow sintering treatment for the manufacturing of dense alumina platelet-reinforced glass matrix composites was proposed for the recycling of glasses coming from dismantled cathode ray tubes (CRTs). Mixtures of three different glasses from CRTs and Al2O3 platelets were investigated regarding the introduction in glass of rigid, non-sintering, inclusions and the nature of the matrix glasses. An innovative short-time sintering procedure was found to be advantageous, leading to significant increases in bending strength, microhardness and fracture toughness, despite the relatively low Al2O3 platelet addition. Both the morphology of the residual porosity, due to the sintering process and particular chemical and physical interactions within the matrix, and the crack deflection effect, due to the specific matrix-reinforcement combination, were found to be the determinant of the observed mechanical properties. The obtained bending strength, Vickers' microhardness and fracture energy are comparable to the values reported for glass-ceramics for technical applications in the building industry.