Fabrication of alumina ceramics with high flexural strength using stereolithography

Additive manufacturing technology (especially stereolithography) is an effective manufacturing to solve ceramic materials with complex structure difficultly due to their inherent brittleness and hardness, which are applied in electrostatic chuck, vortex generators, and catalyst carriers. In present reports, Al2O3 ceramics via stereolithography mostly focused on the rheology of paste and preparation of part. And there is limited research on the high performance for Al2O3 via stereolithography which can meet the industrial application with complex structure. In this study, high performance of Al2O3 ceramics are fabricated and illuminate relationship between material composition, dispersant, sintering process, microstructure, and mechanical properties in detail. To improve the densification and performance of Al2O3 ceramic, introduction of different particle sizes, the type and content of dispersant had been studied to get the higher powder accumulation and solid loading. Besides, the sintering temperature and holding time were investigated. Finally, when the composition of 5 mu m, 3 mu m, and 1 mu m is 40 wt%, 30 wt%, and 30 wt%, the slurry of Al2O3 with 50 vol% was prepared and specimens sintered at 1650 degrees C for a holding time of 4 h has a flexural strength of 482 MPa and apparent porosity of 0.06%.