Fabrication by stereolithography of fiber-reinforced fused silica composites with reduced crack and improved mechanical properties

Chopped quartz fiber-reinforced fused silica (SiO_2f/SiO₂) composites were fabricated by stereolithography. The fiber orientation characteristics and crack distributions after the debinding process of the green bodies were investigated. The results showed that the distribution of fibers presented orientation characteristics; additionally, the number of cracks after debinding decreased as the fiber content increased and the cracks oriented along the fiber orientation. The mechanical properties of SiO_2f/SiO₂ ceramics with different fiber contents were also considered. As a result, a compressive strength of 51.2 MPa and flexural strength of 24.3 MPa were achieved for the SiO_2f/SiO₂ ceramic with 4 wt% fiber, and a sintered cambered structure with a size over 150 mm × 150 mm × 3 mm was fabricated successfully without cracking and deformation for the SiO_2f/SiO₂ composites with a fiber content of 4 wt% and 6 wt%.