Effects of ZrSiO4 content on properties of SiO2-based ceramics prepared by digital light processing

Abstract

SiO2-based ceramic cores are widely used in the preparation of gas turbine engine hollow blades due to their excellent chemical stability and easy removal after casting. In this paper, ZrSiO4 reinforced SiO2-based ceramics were fabricated using digital light processing (DLP) technology. The results showed that the addition of ZrSiO4 reduced the cure depth due to its high UV light absorptivity and refractive index. When the content of ZrSiO4 increased to 15 wt%, the cristobalite content reached the maximum, and radial shrinkage reached the minimum of 1.4%. ZrSiO4 grains could hinder the propagation of cracks, enhancing the room-temperature flexural strength. At 1550 °C, fracturing across SiO2 grains in SiO2-based ceramics led to the great improvement of high-temperature flexural strength. When the content of ZrSiO4 reached 15 wt%, the flexural strength at room temperature and high temperature was 11.5 MPa and 36.7 MPa, respectively. Therefore, the SiO2-based ceramics prepared using DLP technology have good room temperature and high temperature properties, and are expected to be used for hollow blade casting.