Stereolithography Additive Manufacturing and Sintering Approaches of SiC Ceramics

Stereolithography additive manufacturing (SL-AM) has been reported to produce SiC ceramic recently. However, both the density and strength of the stereolithography additive manufactured SiC ceramic need to be improved. In this study, different sintering approaches, including liquid phase sintering (LPS), precursor infiltration and pyrolysis (PIP), and liquid silicon infiltration (LSI), were applied based on the SL-AM prepared SiC green bodies. SiC sintered bodies were finally obtained. In each condition, the relative density, crystalline phases, microstructure, and flexural strength were investigated in detail. The relative density of the LPS-sintered SiC, PIP-sintered SiC, and LSI-sintered SiC ceramics were 78.2 ​± ​1.36%, 82.6 ​± ​0.48%, and 96.2 ​± ​0.32%, respectively. And the strength of the LPS-sintered SiC, PIP-sintered SiC, and LSI-sintered SiC body were 77 ​± ​5.2 ​MPa, 184.2 ​± ​8.5 ​MPa, and 210.4 ​± ​10.3 ​MPa, respectively. The density and strength were compared to each other, as well as other additive manufacturing results and traditional results. At last, LSI is found to be the most promising sintering approach for stereolithography additive manufactured SiC ceramic.