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Materials Science in Additive Manufacturing Ceramic vat photopolymerization

A C

B D

E

F G H

Figure 7. Material synthesis, 3D printed and pyrolyzed SiOC ceramics. The synthesis pathway is illustrated in panel (A-E), showing reagent molecular
configurations and the sol-gel transition process that generates the inorganic network. (F) Images displaying the as-printed polymer precursor and its
pyrolyzed SiOC ceramic counterpart for comparison purposes. (G and H) Microstructural characterizations revealing surface morphology and fracture
patterns of the pyrolyzed octet-truss SiOC ceramic architecture processed at 1000°C. Copyright © 2018 Elsevier. Reprinted with permission of Elsevier
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the compressive strength. In addition, zirconium-based parameters to achieve both lightweight strength and
photosensitive resin was synthesized with metal alkyls, and structural precision requirements, the group successfully
a new zirconium-based photosensitive resin suitable for designed and fabricated various lattices. After pyrolysis,
DLP 3D printing was obtained by optimizing the ratio of fully dense SiOC ceramics with high structural integrity,
each component of the resin, and a porous lattice structure fine surface finish, and exceptionally high carbon-to-
ZrOC ceramic with high specific strength was successfully oxygen ratios were formed. Notably, the octagonal lattice-
prepared. By comparing the macroscopic photos of the structured SiOC ceramics demonstrated a remarkable
samples treated at different pyrolysis temperatures, it can apparent density of 0.33 g/cm and a specific strength
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be found that the product shrank evenly after pyrolysis, reaching 5.74 × 10 N·m/kg, significantly outperforming
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showing a smooth surface and no clogging and cracks previously reported material systems with comparable
inside. The shrinkage rate increased continuously with the densities (Figure 8). This study provides robust theoretical
rise of pyrolysis temperature, concomitant with continuous and technical support for achieving lightweight yet high-
improvement of the product’s mechanical properties. Thus, strength complex ceramic precursor components. The
various metallic precursors such as Fe, Ni, Co, and Pt can breakthrough lies in establishing a material-process-
be incorporated into pre-ceramics to obtain PDCs for performance framework that enables precise control
specific applications. over structural lightweight and mechanical enhancement
To address the complexity of existing photopolymerizable in polymer-derived ceramics, opening new possibilities
ceramic precursor material formulations and processes, for advanced ceramic applications requiring intricate
Chen’s group proposed a simplified approach using three geometries and superior mechanical properties.
commercially available low-cost organic polysiloxane More recently, the research group also developed a
ceramic precursors containing different functional groups/ novel two-stage folding-assisted pyrolysis strategy for
substituents as silicon sources. Through a straightforward 4D printing of shape-programmable PDCs. A two-
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physical blending process, they developed photosensitive step thermal process (300°C pre-pyrolysis followed by
resin formulations for ceramic precursors. The research 1000°C ceramization) enables controlled deformation
focused on investigating key properties and mechanisms and crack mitigation. The first stage fixes folded shapes
including rheological behavior, stability, printability, and via partial decomposition of organic components while
pyrolysis-induced ceramic quality of these precursor creating microchannels for gas release, eliminating stress
resins. By optimizing the printing process and sintering from metal wire fixatives. The second stage achieves

Volume 4 Issue 3 (2025) 13 doi: 10.36922/MSAM025200031