Carlos F. Revelo H, Henry A. Colorado, Geovana C.G. Delaqua, Carlos M. F. Vieira
ABSTRACT Additive manufacturing enables the fabrication of ceramic components with complex geometries and customized designs. This study investigates extrusion-based 3D printing of ceramic bricks using locally sourced kaolinite clay combined with 30wt.% recycled glass and chemical additives (sodium silicate, corn starch, and citric acid) to tailor rheological behavior and printability. Specimens were sintered at 900 and 1000 °C, and their physical, mechanical, and microstructural properties were evaluated. Increasing the sintering temperature enhanced densification, reducing water absorption and porosity while improving compressive strength, with a maximum value of 30.26 MPa obtained for samples containing sodium silicate at 1000 °C. Additives significantly influenced rheology: sodium silicate increased yield stress and viscosity, improving shape stability, whereas citric acid and corn starch enhanced flowability. Microstructural analysis indicated that improved mechanical performance is associated with reduced porosity and enhanced particle bonding due to liquid phase sintering. These results demonstrate the potential of combining recycled glass and tailored additives to optimize printability and performance in sustainable ceramic manufacturing.