Abstract: With the rapid application of additive manufacturing technology in the field of ceramic material fabrication, the development of light cured ceramic slurries with high solid content and low viscosity has become a key content in the complex structure additive manufacturing of various ceramic materials. This article focuses on Si₃N₄ based ceramic composite materials and studies high solid content/low viscosity multiphase ceramic slurries that meet the requirements of photopolymerization additive manufacturing, providing theoretical and technical support for the additive manufacturing of high-performance ceramic parts. The design concept of the slurry system is outlined, including the resin matrix formulation, particle grading strategy, and additive optimization. A composite resin matrix is designed and prepared by mixing the monomer resins HDDA, TMPTA, ACMO, and EA in a mass ratio of 1:1:1:1. A ceramic particle size grading strategy is adopted (particle mass ratio of 1 μm : 0.5 μm : 50 nm = 0.17 : 0.67 : 0.16). The contents of the silane coupling agent KH560 (5% of the total ceramic particle mass), dispersant BYK110 (4% of the total ceramic particle mass), and diluent NMP (20% of the resin mass) are optimized. This ultimately achieved comprehensive improvement in the slurry's rheological properties and printability. At a solid loading of 55.56%, the slurry exhibited a viscosity of 0.79 Pa·s, thixotropy of 553.1 Pa/s, and yield stress of 28.9 Pa. The addition of KH560, BYK110, and NMP reduced the slurry viscosity to 3.87 Pa·s even when the solid loading reached 74 wt%. This study provides theoretical and technical support for the preparation of applicable slurries used in additive manufacturing of high-performance ceramic components.

Key words: light cured ceramics, surface modification, high solid content, low viscosity