# Polymer-Derived SiOC Ceramics by Digital Light Processing-Based Additive Manufacturing
###### Abstract
Currently, 3D printing technology is widely used in the fabrication of PDCs, successfully printing various porous ceramic structures such as SiOC [49,50], ZrOC [51], SiCN [52], and SiO\({}_{2}\)[53]. For instance, [PERSON] et al. [54] employed digital light processing (DLP) 3D printing to fabricate complex, curved, and porous polymer precursor structures. After subsequent pyrolysis, these structures were transformed into uniformly shrinking and dense SiOC ceramics. [PERSON] et al. [55] modified polysilazane ceramic precursors with acrylate monomers and incorporated CNTs as absorbers to fabricate SiCN ceramics with complex structures. The results indicated that the introduction of CNTs effectively adjusted the light-curing thickness and enhanced printing accuracy. Compared to previously reported light-curing ceramic precursor polymers, the samples exhibited improved linear shrinkage, porosity, and ceramic yield after pyrolysis at 1300 \({}^{\circ}\)C. [PERSON] et al. [56] synthesized a low-viscosity, high-curing strength silicone photosensitive resin co-doped with Zr/Ti using the sol-gel method, and they also prepared lattice-structured green parts through DLP \begin{table}
\begin{tabular}{c c c c c c c} \hline
**3D Printing Technology** & **Part Size** & **Speed** & **Surface Quality** & **Process Cost** & **Mechanical Property** & **Preferred Applications** \\ \hline SL & 100 \(\mu\)m–100 cm & Slow & High & Medium & Good & Structural ceramics \\ \hline DLP & 100 \(\mu\)m–100 cm & Medium & High & Medium & Good & Structural ceramics \\ \hline IJP & 100 \(\mu\)m–10 mm & Slow & High & Low & Moderate & Structural ceramics \\ \hline DIW & 100 \(\mu\)m–10 cm & Medium & Low & Low & Moderate & Structural ceramics/ \\ \hline SLS & 10 mm–10 cm & Medium & Low & High & Good &
\begin{tabular}{c} Structural ceramics/ \\ Bioceramics \\ \end{tabular} \\ \hline LOM & 100 mm–10 cm & Fast & Medium & Low & Poor & Structural ceramics \\ \hline FDM & 100 mm–10 cm & Medium & Low & Medium & Moderate & Functional ceramics \\ \hline \end{tabular}
\end{table} 
Table 1: Comparison of the different 3D printing technologies used for ceramic fabrication. printing. The resulting compact SiOC ceramics were pyrolyzed under a high-temperature and nitrogen atmosphere. After pyrolysis at 1200 \({}^{\circ}\)C, the mass loss was 55.9 wt%, and the linear shrinkage was 35.4%. [PERSON] et al. [57] developed various photosensitive preceramics by blending pre-ceramic materials with photosensitive resins, achieving high ceramic yields. This approach was used to fabricate high-strength SiOC structures at the micron scale. This method allows for the tuning of SiOC ceramic properties by adjusting the proportions of different preceramics, as demonstrated in subsequent studies [58]. [PERSON] et al. [59] synthesized a novel UV-curable SiOC ceramic precursor, incorporated SiC whiskers, and employed DLP 3D printing technology to fabricate green parts with complex structures. Pyrolysis at 1000 \({}^{\circ}\)C yielded SiOC ceramics and SiOC-SiCw ceramic composites, with a linear shrinkage rate of 32.8% and a ceramic yield of 48.5%. In this study, we prepared and characterized the rheological properties of a homogeneous polyoxysilane pre-precursor slurry suitable for UV curing using methyl-silsesquioxane resin (SILRES MK) resin as the raw material. During the molding process, the polyoxysilane prepolymer (MK-TMSPM), containing methacrylate-based functional groups, underwent rapid cross-linking and curing through ultraviolet light layer-by-layer curing, thereby resulting in the successful fabrication of three-dimensional diamond and octahedral structures with well-defined forms and smooth surfaces. Subsequently, dense SiOC ceramic material was obtained through sintering in a high-temperature argon atmosphere at 1200 \({}^{\circ}\)C, exhibiting minimal shrinkage and a high ceramic yield (47.6 \(\pm\) 0.1%). The microstructure and mechanical properties of the printed ceramic materials were also studied and discussed.