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Digital light processing (DLP) provides a promising avenue for constructing ceramic parts with high precision and complex shapes, yet the inherent brittleness and strength‐toughness trade‐off hinder their wide applications. Here, according to DLP 3D printing, the textured alumina ceramic components with horizontally aligned textured microstructure were successfully created by adding anisotropically shaped platelets. As a critical process in the preparation of textured ceramics, the alumina platelets were aligned horizontally during printing by using the special shear fields and forming capabilities of DLP technology. The shrinkage, density, microstructure, mechanical performance, and damage‐tolerance behavior of alumina parts with different platelet concentrations were examined, and the toughening mechanisms were investigated. The strength and toughness of ceramics with 5 vol.% platelet addition are increased by 22% and 43%, respectively, as compared with those without platelets. The improved damage tolerance capabilities were primarily ascribed to the collaborative toughening mechanisms stimulated by the platelet addition, including crack branching, crack deflection, uncracked‐ligament bridging, and platelet pull‐out, which increased the crack tortuosity and consumed more fracture energy. The strategy opens up new opportunities to design complex 3D ceramic geometries with bio‐inspired layered or textured architectures, providing optimized damage tolerance. [ABSTRACT FROM AUTHOR]

Si3N4 ceramics with high mechanical properties and thermal conductivity, exhibiting fine and bimodal microstructure, were prepared by adjusting the Er2O3/MgO ratio and hot‐pressing sintering at 1800°C for 4 h. The microstructure, grain distribution, lattice oxygen content, mechanical properties, and crack propagation process of the sintered bulk samples were systematically investigated. It was found that a low Er2O3/MgO ratio contributed to the densification of Si3N4 ceramics, whereas a high Er2O3/MgO ratio favored the grain growth of Si3N4 ceramics. In this research, the grain size distribution and average diameters as well as their impact on mechanical properties were examined. When the ratio of Er2O3/MgO was 3:1, Si3N4 had a larger average diameter and higher thermal conductivity, but the mechanical properties were somewhat reduced. When the ratio of Er2O3/MgO was 2:2, the sample displayed enhanced mechanical performance, which can be explained by the formation of a bimodal structure. The research indicates that it is feasible to control the microstructure and optimize the mechanical properties of Si3N4 ceramics by tailoring the sintering additives. [ABSTRACT FROM AUTHOR]