Study on the Sintering Shrinkage of Photocurable Silicon-Based Ceramic Cores Based on Aluminum-Zirconium Alloy/Silicon Powder Composites

The fabrication of silica-based ceramic cores via Digital Light Processing (DLP) attract considerable research interest. However, the volatilization of organic components within the ceramic slurry during DLP-based forming triggers significant linear shrinkage in the resultant ceramic cores, thereby hindering the attainment of ceramic components with exceptional dimensional accuracy. Aluminum-Zirconium alloy powder was introduced as a filler in this study to regulate the shrinkage behavior of the ceramic components. Furthermore, a Aluminum-Zirconium alloy/nano-Si powder composite filler system was constructed, and its influence on the comprehensive properties of silicabased ceramic cores was systematically investigated. The results show that the sintering shrinkage in the XY direction of silica-based ceramic cores with 3wt.% Aluminum-Zirconium alloy powder addition is nearly zero. When the addition amounts of both Aluminum-Zirconium alloy powder and nano-Si powder are 3wt.%, the linear shrinkage rates of silica-based ceramic cores in the XY and Z directions tend to be consistent. The composite filler modification strategy established in this study provides a reliable technical scheme and experimental support for the DLP additive manufacturing of high-precision and low-shrinkage silica-based ceramic cores.