Structure design influencing the mechanical performance of 3D printing porous ceramics

Different from traditional ceramic materials, three-dimensional (3D) porous ceramics have become a research hotspot in recent years due to combinative of light-weight and high strength. Meanwhile, the 3D printing technique, which can be used to design hierarchical porous structures by combining flexible design and advanced manufacturing procedures, is regarded as a revolutionary and attractive tool for the preparation of 3D porous ceramics. Herein, a novel road is reported for fabricating 3D porous ceramic lattices with excellent mechanical properties by bridging 3D printing and SiC chemical vapor infiltration. The effects of coordination number, rotation angle, hollow structure and sintering temperature on the performance of ceramic lattices were also investigated. As revealed by the results, the cubic lattices possess the highest compressive strength and fracture work, 41.93 MPa and 2126.7 kJ/m², respectively. Among different hollow lattices, the stability and bearing capacity of triangular structures were superior to that of square and honeycomb structures. The compressive strength of the triangular hollow lattices can reach up to 31.20 MPa. And the fracture work of the 3D porous lattices without rotation can be 7 times that of the lattices with a rotation angle of 30° and 45°. Moreover, as the sintering temperature rises, the compressive strength of 3D porous ceramics gradually increases while the shrinkage tends to be more serious. Additionally, the fracture work of 3D porous ceramics reaches its peak at a sintering temperature of 1400 °C. The approach developed in this work provides a simple, economic, and effective way to fabricate 3D porous ceramics, which leads to promising applications in future functional devices.