Influence of Niobium Pentoxide and Sintering Temperature on Mechanical and Electrical Properties of Glass-ceramics Obtained from Recycled Automotive Windshields

Abstract Automotive windshield represents a large volume of solid waste due to limited recycling. Glass-ceramics were produced from discarded windshields with Nb2O5 as a nucleating agent at concentrations of 0, 5, 10, and 15 wt% at 700 and 800 °C sintering temperatures. Mechanical and electrical characterizations of glass-ceramics were performed. Equibiaxial flexural strength was performed and related to porosity. At 700 °C, Nb2O5 favors the monoclinic NaNbO3 phase with perovskite structure. At 800 °C, high Nb2O5 content formed crystalline phases of perovskite and quartz. Dielectric constant and electrical conductivity increased with the addition of Nb2O5, reaching 64 and 4.3 μS/m for 15 wt% Nb2O5 at 700oC. At 800oC, niobium pentoxide reduces the biaxial flexural strength from 28.7 to 14.4 MPa; while increasing the electrical conductivity from 0.10 to 0.33 µS/m for samples with 0 and 15 wt%.