Preparation and properties of nano-MgO reinforced DLP 3D printed alumina ceramic cores

Complex-structured ceramic cores are critical components in the manufacture of aero-engine hollow blades. Nevertheless, traditional preparation processes are heavily dependent on molds, which significantly hinders the achievement of complex configurations. DLP 3D printing technology offers a new way to produce high-performance ceramic cores. However, challenges remain in controlling key properties such as porosity and mechanical strength, which hinders their widespread adoption. The effect of nano-MgO (0–8 wt.%) on the performance of alumina-based ceramic cores produced via DLP 3D printing was examined. It was observed that the room-temperature strength of the core first increases and subsequently decreases; meanwhile, the porosity shows a gradual increase, and the surface roughness first diminishes and then rises. The addition of 4 wt% nano-MgO effectively reduces interlayer cracks in sintered samples, thereby achieving the collaborative optimization of multiple properties. Furthermore, this addition ensures good surface quality with a surface roughness value of 2.21 μm, while simultaneously providing an appropriate porosity of 36.35%, a room-temperature bending strength of 58.62 MPa, and a high-temperature deflection of 3.23 mm. This research provides an important foundation for the improvement of DLP-printed ceramic cores and exhibits great promise for application in the casting of hollow turbine blades.