Influence of Resin Composition on the Photopolymerization of Zirconia Ceramics Fabricated by Digital Light Processing Additive Manufacturing.

Digital light processing (DLP) is widely recognized as one of the most promising additive manufacturing technologies for ceramic fabrication. Nevertheless, during the additive manufacturing of zirconia ceramics, debinding and sintering often lead to structural defects, which severely deteriorate the material properties and hinder their broader application. In this study, we added an oligomer into the photosensitive resin and systematically investigated the effects of oligomer content on the viscosity and curing properties of ceramic suspensions. The results demonstrated that the introduction of oligomers is conducive to enhancing the crosslinking density and reducing defects. Finally, a 45 vol% solid content zirconia ceramic slurry was prepared by adding 20 wt% oligomers to the resin system. After printing, debinding, and sintering, the final zirconia ceramics exhibited a uniform microstructure without delamination or cracks, its bending strength reached 682.4 MPa. This study demonstrates that zirconia ceramics fabricated by photopolymerization with oligomer photosensitive resin exhibit excellent mechanical properties, significantly expanding the potential applications for high-performance zirconia ceramic components with additive manufacturing.