The fabrication of fiber-reinforced polyamine-coated silica paste and the mechanical properties of SiO2f/SiO2 composites via stereolithography combined with silica sol impregnation

Fused silica ceramic (SiO 2 ) was modified by polyamine (PDA), and the FTIR , TG, XPS and SEM analyses demonstrated that PDA was successfully coated on the surface of SiO 2 ceramic. Subsequently, the quartz fiber-reinforced PDA-coated silica ceramic (SiO 2 f / m -SiO 2 ) paste was prepared, and the rheological behaviors and cured depth (C d ) of the pastes and the lateral overcuring error of the green body were investigated. The results showed that the viscosities and C d of SiO 2 f / m -SiO 2 paste significantly decreased and the lateral overcuring error of the green body greatly decreased after modifying by PDA. Based on stereolithography combined with silica sol impregnation, the SiO 2 f / m -SiO 2 composites were fabricated and the influence of impregnation times on mechanical properties of SiO 2 f / m -SiO 2 composites was explored. As a result, the mechanical properties were improved along with the impregnation time increasing, and additionally, the flexural strength was 28.9 MPa and compression strength was 72.3 MPa when impregnating three times.