Effect of Fused Silica Fiber on the Shrinkage and Properties of Silica Based Ceramic Core

Abstract

To improve the dimensional accuracy and high-temperature performance of ceramic core, the content of fused silica fiber and its length effects on mechanical and dimension behavior of silica-based ceramic cores were investigated. In order to simulate the single crystal blades casting process, the sintered samples were also heated up to 1550 °C and kept for 0.5 h. The sintering and as-cast shrinkage, creep deformation and bending strength were characterized. The result showed that fused silica short fiber could obviously reduce the shrinkage rate of ceramic core. Short fiber has an anisotropic effect on inhibition of contraction. The shrinkage in the direction of length and injection direction was less than that of the other direction. The fused silica fiber with higher length/diameter ratio maintains the creep deformation resistance at high-temperature acting as skeleton structure.