Research on Rheology and Formability of SiO₂ Ceramic Slurry Based on Additive Manufacturing Technology via a Light Curing Method

Abstract

SiO 2 ceramic parts with complex structures were formed by additive manufacturing technology via a light curing method combined with a heat treatment process. To reveal the influence mechanism of rheology and formability of SiO 2 ceramic slurry, the microstructure, morphology, and properties of light-cured SiO 2 ceramic samples were characterized by a viscosity test, thermogravimetric analysis (TG-DTG), X-ray diffraction (XRD), a scanning electron microscope (SEM), and a series of tests for physical properties (bending strength, mass burning rate, and densification). The results indicate that the main effect of the dispersant-type factor was more significant than the pH value. When the dispersant was ammonium polyacrylate (PMAA-NH 4 ) with a content of 1.0 wt % and the pH value of the slurry system was 9, the viscosity of SiO 2 ceramic slurry could be controlled to the lowest. It was also found that the sintering temperature in the experiment had no effect on the crystalline phase of SiO 2 ceramics. When the sintering temperature was 1250 °C and the solid content was 65 vol %, the micromorphology of the samples was uniform. Under this condition, the bending strength of the sample reached 14.9 MPa and the densification was 76.43%.

Comprehensive Review on Fabricating Bioactive Ceramic Bone Scaffold Using Vat Photopolymerization

“…As shown in Figure a, the viscosity of the slurry increases with the increase in solid loading due to the interaction between the ceramic particles . Fine ceramic particles are easier to agglomerate than coarse ceramic powders because surface energy rises with decreasing particle size, resulting in increased viscosity (Figure b), but the dispersion of fine powders could improve the stability of the slurry. − The particle size should be chosen to avoid approaching UV wavelengths, as this could exacerbate light scattering . Chen et al reported that ceramic suspension with a particle size of 0.35 μm had the best stability compared to 7.41 and 3.00 μm, with almost zero sedimentation ratio after 100 days of sedimentation tests.…”