In this study, a process is developed for 3D printing with alumina (Al₂O₃). First, a photocurable slurry made from nanoparticle Al₂O₃ powder is mixed with hexanediol diacrylate binder and phenylbis(2,4,6-trimethylbenzoyl) phosphine oxide photoinitiator. The optimum solid content of Al₂O₃ is determined by measuring the rheological properties of the slurry. Then, green bodies of Al₂O₃ with different photoinitiator contents and UV exposure times are fabricated with a digital light processing (DLP) 3D printer. The dimensional accuracy of the printed Al₂O₃ green bodies and the number of defects are evaluated by carefully measuring the samples and imaging them with a scanning electron microscope. The optimum photoinitiator content and exposure time are 0.5 wt% and 0.8 s, respectively. These results show that Al₂O₃ products of various sizes and shapes can be fabricated by DLP 3D printing.

W-10vol.%ZrC composites reinforced by micrometric and nanosized ZrC particles were prepared by hot-pressing of 25 MPa for 2 h at 1900°C. The effect of ZrC particle size on microstructure and mechanical properties at room temperature and elevated temperatures was investigated by X-ray diffraction analysis, scanning electron microscope and transmission electron microscope observations and the flexural strength test of the W-ZrC composite. Microstructural analysis of the W-ZrC composite revealed that nanosized ZrC particles were homogeneously dispersed in the W matrix inhibiting W grain growth compared to W specimen with micrometric ZrC particle. As a result, its flexural strength was significantly improved. The flexural strength at room temperature for W-ZrC composite using nanosized ZrC particle being 740 MPa increased by around 2 times than that of specimen using micrometric ZrC particle which was 377 MPa. The maximum strength of 935 MPa was tested at 1200°C on the W composite specimen containing nanosized ZrC particle.