Enhancing creep resistance performance in silica-based ceramic core materials through shell-core structure

Abstract

The creep behavior of silica-based ceramic cores significantly impacts dimensional precision in investment casting. This study focuses on synthesizing an alumina coating on fused silica surfaces to create a shell-core structure. The creep behavior of silica-based ceramic cores was explored. Specifically, the influence of the shell-core structure on their creep mechanism was investigated. The results revealed the excellent creep resistance of silica-based ceramic cores with shell-core structures. The softening deformation of particles and the viscous flow of the glass phase were observed to account for the differences in creep behavior. The alumina shell structure reinforced the powders, effectively inhibiting the softening deformation of the core structure. Notably, the shell-core structure not only suppressed the viscous flow of the glass phase, thereby weaking the pore filling process, but also promoted the mullitization reaction. This reaction accelerated the consumption of the glass phase, enhancing the creep resistance of the silica-based ceramic cores.