Fabrication of High‐Density Reaction‐Bonded SiC via Vat Photopolymerization 3D Printing

ABSTRACT Vat photopolymerization (VP) for silicon carbide (SiC) ceramics enables high precision and manufacturing efficiency, offering an optimal route for the rapid production of lightweight SiC mirrors. However, the limited cure depth of the slurry remains a primary challenge. This study introduces polymethyl methacrylate (PMMA) microspheres into the slurry to enhance the cure depth, combined with an integrated process of VP additive manufacturing, precursor infiltration and pyrolysis (PIP) cycles, and reaction sintering to fabricate SiC ceramics. Results demonstrate that PMMA particle size and mass fraction, along with PIP cycle count, significantly affect the final mechanical properties. Notably, ceramic density did not continuously increase with additional PIP cycles during reaction sintering. Optimal performance was achieved using 10 µm PMMA with three infiltration cycles, yielding a maximum density of 3.05 g/cm 3 and flexural strength of 274 ± 29 MPa, with only 10.36% residual free silicon. This study provides a feasible manufacturing strategy and performance optimization insights for stereolithography‐based additive manufacturing of SiC ceramics.