Microgroove-Assisted Film Patterning for the Control of Layered Microstructures in 3D-Printed Ceramics

In the artificial fabrication of microstructured ceramics with platelets, precisely controlling the local alignment of microstructural units and constructing complex macroscopic geometries remain critical challenges. Herein, an inert film with microgrooves is introduced into the ceramic printing process, and a novel microgroove-assisted ceramic stereolithography approach is proposed. By combining microgroove geometry and layered printing, the local flow field generated during platform positioning through the interaction between the slurry and the microgrooves is harnessed to drive the orientation of alumina platelets and to form layered microstructures and non-flat interfaces between layers. The flow-driven orientation mechanism of the platelets is elucidated. After sintering, grain orientations are effectively controlled, and microgroove-scale textured microstructures are introduced within each layer. A gradient distribution of hardness is formed along the microgroove. The warpage in the sintered samples is reduced. These layered microstructures further influence crack extension and deflection. Printing results using films with pits and letter arrays demonstrate that this mechanism can form more complex microstructures. This approach provides a fast, stable, and effective flow-driven orientation mechanism for platelets in high-solid-content ceramic slurry, which controls the layered distribution of designed microstructure patterns within the 3D-printed ceramics.