Vat Photopolymerization of Additively Manufactured Zirconia Ceramic Structures from Slurries of Surface Functionalized Particles: A Critical Review

Zirconia (ZrO2) ceramics and composites have attracted much attention in aerospace, biomedical and energy fields due to their high hardness, high wear resistance, excellent chemical stability and biocompatibility. However, the brittleness of ceramics and the high cost of molds have made it difficult for traditional processing techniques to manufacture complex structural and functional components efficiently. Additive manufacturing technology has successfully overcome these challenges by optimizing the preparation process and improving production efficiency. Among them, vat photopolymeriztion (VPP) has been demonstrated to offer distinct advantages, including high precision, high efficiency and low cost. It provides a novel approach to the preparation of zirconia ceramics. VPP preparation of zirconia ceramics and composites needs to consider various steps such as slurry preparation, structural design and printing, debinding and sintering. This review introduces common VPP technologies related to zirconia ceramics and summarizes the factors affecting the rheological and curing properties of zirconia slurry, in order to provide researchers with a reference for studying VPP preparation of zirconia. The current optimization methods for light-curing zirconia slurry formulations are focused on, and common methods for surface modification and optimization of slurry composition and solid loading are introduced. The influencing factors of the printing process are summarized, and the current research on surface texturing of VPP preparation and the influence of printing parameters on the performance and accuracy of the components are introduced. The effects of debinding/sintering processes on cured zirconia ceramics are also summarized. The applications of VPP zirconia ceramics and composites are proposed, especially for their use in biomedical and energy applications.