Fabrication of Al₂O₃ ceramic cores with high porosity and high strength by vat photopolymerization 3D printing and sacrificial templating

When preparing ceramic materials, high porosity and high strength are often played against each other. How to balance porosity and strength has become a core issue in the 3D printing of ceramic cores. In this work, alumina ceramic cores with a high porosity (36.93%) and a high flexural strength (75.4 MPa) were prepared by combining the vat photopolymerization 3D printing with sacrificial templating. The porosity of alumina ceramic cores was improved by the sacrificial templating method, and the flexural strength was enhanced with alumina particle grading. The effects of pore former (PMMA) content and particle size on the shrinkage, porosity, microstructure, and comprehensive performance of alumina ceramic cores were investigated to reveal the mechanism of simultaneous high porosity and high strength.