Material Strength Analysis of Glazes Derived from Soda Lime Cullet on Ceramic Tiles

Abstract

Strength analysis is a mechanical reliability assessment used to determine the probability of material failure and to establish whether applied stress exceeds material strength. This study evaluated the strength and strain characteristics of studio-produced glazes derived from soda-lime cullet and applied to ceramic tiles. Beverage glass bottles and windowpane glass were collected from waste dumps, garbage cans and construction sites, washed, heated at 120 °C to remove residual oily stains, pulverised and sieved to obtain compatible particle-size densities for glaze preparation. Particle-size density determined by the Blaine method was 2280 kg/m³ for the cullet samples and clay, and 3110 kg/m³ for borax, soda ash and potash. Oxide properties were examined using the Particle-Induced X-ray Emission technique. Glaze batches were formulated by milling the cullet with ball clay and selected fluxes, namely borax, soda ash and potash, before application to biscuit-fired ceramic tiles and glaze firing at 950 °C. Mechanical performance was assessed using a digital universal testing machine under compressive loading. The oxide analysis showed that the cullet samples contained 63.73-78.30% SiO2, 12.81-13.85% Na2O, 4.94-7.16% CaO and 0.67-3.37% MgO. Windowpane cullet produced more melt-glossy outputs than beverage cullet. Among the glaze recipes, WtwCB and WblCB showed the highest resistance to break, with compressive strength/strain values of 1.16162 MPa/0.15608 mm/mm and 1.26268 MPa/0.22542 mm/mm, and Young’s modulus values of 14.653498 N/mm² and 15.550096 N/mm², respectively. The results indicate that selected soda-lime cullet compositions, when combined with appropriate fluxes, can produce visually acceptable and mechanically resistant glazes for ceramic tiles.