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

SiO₂ 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 SiO₂ ceramic slurry, the microstructure, morphology, and properties of light-cured SiO₂ 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-NH₄) with a content of 1.0 wt % and the pH value of the slurry system was 9, the viscosity of SiO₂ 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 SiO₂ 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%.