Accuracy controlling and mechanical behaviors of precursor-derived ceramic SiOC microlattices by projection micro stereolithography (PμSL) 3D printing

Precursor-derived ceramic SiOC (PDC-SiOC) microlattices exhibit excellent oxidation resistance, high-temperature stability, and superior mechanical properties. However, the printing accuracy of the PDC-SiOC microlattices by 3D printing is still limited, and mechanical properties of the PDC-SiOC microlattices have not been studied systematically. Here, PDC-SiOC octet microlattices were fabricated by projection micro stereolithography (PμSL) 3D printing, and photoabsorber (Sudan III)’s effect on the accuracy was systematically analyzed. The results showed that the addition of Sudan III improved the printing accuracy significantly. Then, the ceramization process of the green body was analyzed in detail. The order of the green body decreased, and most of their chemical bonds were broken during pyrolysis. After that, the PDC-SiOC microlattices with different truss diameters in the range of 52–220 μm were fabricated, and their mechanical properties were investigated. The PDC-SiOC microlattices with a truss diameter of 52 μm exhibited higher compression strength (31 MPa) than those with bigger truss diameters. The size effect among the PDC-SiOC microlattices was analyzed. Our work provides a deeper insight into the manufacturing of PDC-SiOC micro-scaled architectures by 3D printing and paves a path to the research of the size effect in ceramic structures.