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Abstract The macro-porous ceramics has promising durability and thermal insulation performance. As porous ceramics find more and more applications across many industries, a cost-effective and scalable additive manufacturing technique for fabricating macro-porous ceramics is highly desirable. Herein, we reported a facile additive manufacturing approach to fabricate porous ceramics and control the printed porosity. Several printable ceramic inks were prepared, and the foaming agent was added to generate gaseous bubbles in the ink, followed by the direct ink writing and the ambient-pressure and room-temperature drying to create the three-dimensional geometries. A set of experimental studies were performed to optimize the printing quality. The results revealed the optimal process parameters for printing the foamed ceramic ink with a high spatial resolution and fine surface quality. Varying the concentration of the foaming agent enables the controllability of the structural porosity. The maximum porosity can reach 85%, with a crack-free internal porous structure. The tensile tests showed that the printed macro-porous ceramics possessed enhanced durability with the addition of fiber. With a high-fidelity three-dimensional (3D) printing process and the precise controllability of the porosity, we showed that the printed samples exhibited a remarkably low thermal conductivity and durable mechanical strength.
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Additive manufacturing of textured barium titanate ceramics via shear force‐induced platelet alignment
Abstract This study explores the potential of single crystal barium titanate (BTO) platelets to fabricate nontoxic ceramics with enhanced material properties through texturization of grain structure. The proposed methodology relies on direct ink write additive manufacturing to enable grain‐oriented growth of BTO ceramics by utilizing a combination of spherical and platelet‐shaped particles. The use of platelet‐shaped particles in the ceramic ink guides particle alignment parallel to the build plate due to shear forces at the nozzle during the printing process. While platelet contents ranging from 0 to 40 wt.% showed a decrease in density as the content increased, experimental data revealed an incremental trend between platelet content, dielectric properties, and the degree of alignment of the particles on the F200 crystal plane, achieving a maximum texturized orientation of 65%. Such orientation resulted in 29.55% improved dielectric properties compared with randomly oriented BTO ceramic. The findings of this research validate the effectiveness of additive manufacturing technologies to tailor the microstructural characteristics of ceramics for specific functional applications.
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- Award ID(s):
- 2204750
- PAR ID:
- 10575256
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- International Journal of Ceramic Engineering & Science
- Volume:
- 7
- Issue:
- 2
- ISSN:
- 2578-3270
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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