Investigating the relation between debinding atmosphere and mechanical properties of stereolithography-based three-dimensional printed Al₂O₃ ceramic

Ceramic green bodies fabricated by stereolithography-based three-dimensional printing technology often have high loading of ultraviolet curable resins, which produce undesirable phenomena such as cracking, deformation, and blistering during the debinding process. Results showed that compared to argon and vacuum, air atmosphere provided higher flexural strength owing to the elevated density. The differences in microstructure between specimens prepared under these atmospheres were attributed to exothermic oxidation reactions occurred under air when compared to endothermic pyrolysis reactions under vacuum and argon. The debinding atmosphere showed little effect on crystallite size due to the elevated sintering temperature, which would determine the final crystallite size of Al₂O₃. Debinding under air atmosphere resulted in flexural strength of 176.69 MPa and open porosity of 23.4%. The flexural strength of the ceramics debinded in air was 21.6% higher than the ceramics debinded in argon atmosphere.