Effect of SiO2 content on properties of SiC ceramic slurry and green body for stereolithography 3D printing

The stereolithography 3D printing technology provides a new technical solution for the preparation of complex structure SiC ceramic parts, but the characteristics of high light absorption and high refractive index of SiC lead to a common problem that printing is difficult to cure. SiO2 with low absorbance and low refractive index was added to SiC ceramic matrix powder as filler to improve the curing property and printing accuracy of SiC ceramic paste. The effects of different amounts of SiO2 on the rheology, stability and curing properties of the slurry and its mechanism were studied. The green body with high precision and good surface quality was prepared by stereolithography 3D printing technology, and the microstructure and properties of the green body were tested and analyzed. The results show that the adding SiO2 to the SiC slurry can reduce the viscosity, improve the stability, and improve the curing property of the slurry. The addition of SiO2 can significantly improve the surface roughness of the SiC green body and make the bending strength increase at first and decrease then.