Research progress in dimensional accuracy control of ceramic cores prepared by vat photopolymerization additive manufacturing

Ceramic cores are critical components for forming complex cooling channels in the investment casting of hollow aero-engine blades, and their dimensional accuracy directly determines the structural quality of the internal cavities and the casting yield of the blades. Due to its high resolution, high efficiency, and mold-free processing capability, vat photopolymerization additive manufacturing has shown great promise for the fabrication of complex ceramic cores. However, issues such as the stair-step effect, shrinkage-induced cracking, phase-transformation-induced fracture, and high-temperature creep still arise during printing, debinding and sintering, and casting service, thereby severely compromising the dimensional accuracy of the cores. Focusing on the entire lifecycle of ceramic cores, from raw materials to fabrication and service, this paper reviews the key factors affecting the dimensional accuracy of ceramic cores fabricated by vat photopolymerization additive manufacturing at different stages, together with the underlying mechanisms. Particular attention is given to the effects of slurry composition, printing parameters, sintering behavior, and high-temperature service conditions on dimensional stability. Finally, future development trends in this field are discussed, with emphasis on the design of high-performance slurries, the coordinated optimization of printing and sintering, as well as the establishment of dimensional accuracy evaluation methods and standard systems for engineering applications.