Heterogeneous Composite Design and 3D Printing Parameter Optimization of Al2O3 Ceramic Triply Periodic Minimal Surface Structures.

Triply Periodic Minimal Surface (TPMS) Al2O3 ceramic structures hold significant potential for applications in biomedical engineering, catalytic systems, and thermal management technologies, which can be fabricated with high precision using vat photopolymerization-based digital light processing (DLP). However, conventional homogeneous designs for TPMS often do not fully meet advanced performance requirements, while the curing depth, a key parameter governing the dimensional accuracy and mechanical performance, has not been thoroughly investigated. To address these limitations, this study proposes an algorithm based on target porosity for designing complex graded and heterogeneous TPMS structures, followed by fabrication via DLP with optimized process parameters. The results demonstrate that the fabricated gradient-porosity TPMS scaffold under optimal parameters exhibited high performance, including dimensional accuracy exceeding 98.5%, a surface roughness as low as 1.21 μm, and a compressive strength of 38.44 MPa. These findings provide valuable references for both the design optimization and reliable DLP strategies of complex ceramic heterogeneous TPMS structures.