Preparation and characterization of Ce-ZrO2/Al2O3 composites by DLP-based stereolithography

This work investigates the printability of Ce-ZrO2/Al2O3 composites through a Digital Light Processing (DLP) technology. Commercially available 10 mol% CeO2 and 12 mol% CeO2-stabilized zirconia were mixed with alumina powders, to provide 11 mol% CeO2-stabilized ZrO2/16 vol% Al2O3 (Ce-ZA16) composite materials. The powders were dispersed under wet conditions, and the homogeneous nanometric dispersion was maintained once added into the liquid monomer. Slurries at several solid loadings were explored, with and without dispersant addition. First, the key role of the dispersant to significantly enhance the solid loading and thus the sintered density was demonstrated. Second, among different dispersant-added slurries at various solid loadings, ranging from 65 to 80 wt%, the best compromise between rheological behavior and curing depth was established. The best formulations, comprised between 70 and 80 wt%, successfully provided fully dense and completely homogeneous composites.