Lithography-Based Additive Manufacturing of Cellular Ceramic Structures

Lithography-based additive manufacturing technology is a layered manufacturing approach where liquid photopolymerizable resins are solidified with ultraviolet, visible, or infrared light. Using a system based on digital mirror devices, photopolymers can be exposed selectively in order to build parts with defined geometries. By modifying the system with a rotating building platform, suspensions with a high solid loading of ceramic powders can be processed, despite the high viscosity of these resins. Depending on the field of application, various formulations were developed for fabricating customized ceramic parts made of alumina, tricalcium phosphate, or bioactive glasses, respectively. On the one hand the influence of the ceramic filler on the mechanical properties is characterized, on the other hand the good precision and the high surface quality of the process system is discussed. For alumina filled resins a solid loading of 50?vol% was used to obtain fully dense parts (>99% of theoretical density) with high fracture strength (biaxial strength of 516?MPa).