Debinding and Sintering of Ceramic Cores for Complex Hollow Turbine Blades: Recent Progress and Challenges

ABSTRACT

The increasing complexity of internal cooling structures in aero‐engine and gas‐turbine blades imposes stringent requirements on the dimensional accuracy, structural integrity, high‐temperature stability, and leachability of ceramic cores. Debinding and sintering are critical heat‐treatment steps that convert organic‐containing green bodies into inorganic porous skeletons suitable for investment casting. This review summarizes recent progress in debinding and sintering processes for SiO ₂ ‐based, Al ₂ O ₃ ‐based, and multiphase composite ceramic cores, with emphasis on material constraints, organic‐phase decomposition, gas release, residue control, sintering‐neck formation, pore evolution, shrinkage, and interfacial stability. Particular attention is paid to vat‐photopolymerized ceramic cores, in which high resin contents and layered architecture increase the risk of cracking, delamination, warpage, anisotropic shrinkage, and defect inheritance. The reviewed studies indicate that ceramic‐core sintering is better understood as a controlled densification process, in which strength development must be coordinated with connected porosity, dimensional stability, and leachability. Defects generated during debinding, including residual carbon, microcracks, pore gradients, and weak interlayer interfaces, strongly affect subsequent sintering shrinkage and microstructural evolution. Future work should establish integrated debinding‐sintering optimization frameworks that couple material formulation, staged thermal treatment, atmosphere control, support strategies, dimensional compensation, and casting‐performance evaluation, thereby improving the manufacturability and reliability of ceramic cores for complex hollow turbine blades.