Effect of basalt aids on the thermal stability and mechanical properties of zircon composites produced by slip casting

Abstract This study explores the feasibility of producing cost‐effective zircon–basalt composite ceramics using slip casting method. Zircon is effectively stabilized by basalt up to 1550°C, preventing its decomposition; however, challenges such as gas release and partial melting during sintering result in increased porosity and reduced mechanical strength. Thermal analysis, including thermogravimetric and differential thermal measurements, identified a stepwise mass loss in basalt beginning 600°C, attributed to the sublimation of chlorine‐ or fluorine‐containing compounds. Visual thermal analysis determined a melting point of 1300°C ± 50°C for basalt. Scanning electron microscopy revealed pore formation from gas release and the presence of zircon grains within an anorthite matrix. Microhardness increased with both basalt content and sintering temperature, while flexural strength showed an inverse relationship, highlighting the negative impact of porosity. These findings demonstrate the complex interaction between composition, processing parameters, and microstructure in determining the mechanical properties of zircon–basalt composites. To mitigate the challenges of gas release and porosity, further optimization could involve refining the sintering parameters, such as lowering the heating rate or introducing additional additives to trap volatile species, thereby improving the material's densification and mechanical integrity.