BaTiO₃ (BTO) ceramics were fabricated based on stereolithography technology. The microstructures and electric properties of the BTO ceramics were studied. X-ray patterns of sintered BTO ceramics indicated that the tetragonal phase had formed, and the grain size increased clearly as BTO weight percentage increased. Moreover, the BTO ceramics exhibited good electric properties, with a piezoelectric constant d₃₃ of 166 pC/N at 80% BTO weight percentage. To evaluate the properties of 3D printed BTO ceramics, a 1.4 MHz focused ultrasonic array was fabricated and characterized. The −6dB bandwidth of the array was 40%, and the insertion loss at the center frequency was 50 dB. The results show that the printed BTO ceramics array have good potential to be used in ultrasonic transducers for various applications.

In this study, the chemical precipitation coating (CP) process was creatively integrated with DLP-stereolithography based 3D printing for refining and homogenizing the microstructure of 3D printed Al₂O₃ ceramic. Based on this novel approach, Al₂O₃ powder was coated with a homogeneous layer of amorphous Y₂O₃, with the coated Al₂O₃ powder found to make the microstructure of 3D printed Al₂O₃ ceramic more uniform and refined, as compared with the conventional mechanical mixing (MM) of Al₂O₃ and Y₂O₃ powders. The grain size of Al₂O₃ in Sample CP is 64.44% and 51.43% lower than those in the monolithic Al₂O₃ ceramic and Sample MM, respectively. Sample CP has the highest flexural strength of 455.37±32.17 MPa, which is 14.85% and 25.45% higher than those of Samples MM and AL, respectively; also Sample CP has the highest Weibull modulus of 16.88 among the three kinds of samples. Moreover, the fine grained Sample CP has a close thermal conductivity to the coarse grained Sample MM because of the changes in morphology of Y₃Al₅O₁₂ phase from semi-connected (Sample MM) to isolated (Sample CP). Finally, specially designed fin-type Al₂O₃ ceramic heat sinks were successfully fabricated via the novel integrated process, which has been proven to be an effective method for fabricating complex-shaped Al₂O₃ ceramic components with enhanced flexural strength and reliability.

Due to high light absorption and high refractive index of silicon nitride (Si₃N₄) ceramic, it is difficult to prepare Si₃N₄ slurry with favorable curing ability, high solid loading and low viscosity at the same time, and thus the high-quality Si₃N₄ parts are hard to fabricate via Digital Light Processing (DLP). In this paper, the oxidation process was used to enhance the curing behavior of Si₃N₄ slurry, and then silane coupling agent (KH560) was used to improve the rheological properties of the oxidized Si₃N₄ slurry. The effect of Si₃N₄ slurry with oxidation and modification on its rheological behavior, light absorption, curing ability and stability have been systematically investigated. A Si₃N₄ slurry with abundant photocuring ability, high solid loading, low viscosity and reliable stability was fabricated by the oxidized (1 h) and KH560 (1 wt.%) modified Si₃N₄ powders, and the dense Si₃N₄ ceramic parts were produced by this slurry via DLP 3D printing. Subsequently, the influence of oxidation and modification on microstructure, mechanical properties and thermal conductivity have been investigated. Finally, the microstructure and performances of Si₃N₄ ceramic were compared between different forming processes (including: DLP and cool isostatic pressing).