Fabrication of dense aluminum nitride ceramics via digital light processing-based stereolithography

In this research, we report a novel approach to fabricate complex-shaped aluminum nitride (AlN) ceramics via digital light processing (DLP)-based stereolithography . The rheological behaviors, curing kinetics, and mechanical properties were investigated. Compared to unmodified AlN powders, AlN powders modified by stearic acid and oleic acid showed better wettability with resin. The excess cure widths, cure depths, and depth sensitivities of the AlN suspensions with modified powders were decreased. However, their critical energy was increased because of the increased absorbance of the modified AlN powders. Finally, complex-shaped AlN ceramic parts were fabricated by DLP with sintered-body relative densities exceeding 99% of the theoretical density. The flexural strength and hardness of the sintered sample were 398 ± 10.4 MPa and 10.47 ± 0.08 GPa, respectively, indicating prospective applicability in the industry.