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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]

A composite dispersant was selected to prepare low-viscosity ceramic slurry, and the thick-walled (>3 mm) SiO2 hollow hexagonal ceramic part was prepared by the self-developed ceramic 3D printer and DLP (digital light processing) process. The accuracy of the green body was all within 50 pm in three dimensional directions. The thermal decomposition process of 3D printing ceramic green bodies in air atmosphere or argon atmosphere was analyzed, and the influence of atmosphere on the degreasing and sintering of thick-walled (>3 mm) SiO2 ceramic parts was analyzed. The process of rapid degreasing and sintering of thick-walled (>3 mm) 3D printing SiO2 ceramic body was analyzed by SEM. The argon atmosphere is conducive to the rapid degreasing and sintering of the thick-walled SiO2 ceramics. The thick-walled (> 3 mm) SiO2 ceramic part was prepared rapidly by controlling the gas flow in argon atmosphere. The period of degreasing and sintering is greatly shortened to 21.8 h. Compared with the preparation period of the slurry and its process imported from a foreign company (The preparation period of the company's slurry and process to prepare the same product is 283 h), it is shortened by 92.3%. And it is more than 82% shorter than the preparation period of the SiO2 ceramic hollow blade prepared by the same process in public reports, which reflects the advantages of 3D printing formless rapid prototyping technology, and has great significance for the practical application of SiO2 ceramic 3D printing technology. [ABSTRACT FROM AUTHOR]

This paper focuses on the dispersion of ceramic powder in photosensitive resin. The effects of powder properties, dispersant type and dosage, and solid content on the rheological properties of stereolithography ZrO2 ceramic slurry were studied. The result shows that the properties of the powder have a significant impact on the rheological properties of the slurry, the use of ZrO2 powder with a smaller specific surface area and higher sphericity is more conducive to the preparation of low viscosity and high solid content slurry. The rheological properties and stability of the slurry are mainly controlled by the type and dosage of dispersant, using X-100 with a relative powder mass of 4% as a dispersant, the rheological properties and stability of the prepared ceramic slurry are better. The experimental result of the solid content of the slurry shows that the relationship between the solid content of the slurry and the viscosity satisfies the Krieger-Dougherty model. And the dispersion mechanism of the dispersant has been studied. By the research of this experiment, the foundation has been laid for the high-precision molding of the light-cured ZrO2 ceramic slurry. [ABSTRACT FROM AUTHOR]

The Ca(1+x)/2Sr(1+x)/2Zr4P6‐2xSi2xO24 (CSZP6‐2xS2x, 0 ≤ x ≤ 0.3) ceramics were prepared using powders synthesized by co‐precipitation method, and the effects of Si4+ substitution on the structure, mechanical, and thermal expansion properties were investigated. The optimum sintering time was 4 hours, which greatly shortened the sintering process. By controlling the appropriate composition and sintering temperature, a single phase with the typical NaZr2P3O12 structure was obtained. As a function of x increasing, the parameter a increased and then decreased, while the parameter c and unit cell volume both increased. The mechanical property of CSZP6‐2xS2x ceramics was affected with increasing amount of Si4+ content. The Si4+ substitution could increase the thermal expansion anisotropy and lead to the generation of microcracks, which are responsible for the increase in the amount of hysteresis between heating and cooling curves. The thermal expansion decreased progressively from 1.8 to 0.8 × 10−6/°C. The investigations indicate that the CSZP6‐2xS2x ceramics are potential materials in high temperature applications [ABSTRACT FROM AUTHOR]