Polymer derived gel-like preceramic precursor of core-shell silicon oxycarbide ceramic for robocasting. Issue 17 (1st December 2019)

• Record Type: Journal Article
• Authors: Hu, Lung-Hao; Wang, Yu-Kai; Wang, Sheng-Chang
• Is Part Of: Ceramics international. Volume 45:Issue 17(2019)Part B
• Page Start: 23475
• Page End: 23481
• Publication Date: 2019-12-01
• Subjects: Robocasting -- Gel-like preceramic precursor -- Core-shell silicon oxycarbide ceramic -- Polysilazane precursor; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2019.08.053
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: The conventional techniques for 3D printing ceramic parts are the ceramic powder laser sintering and lithography process that are usually costly in equipment and materials. A low-cost technique for robocasting ceramic has been developed via polysilazane preceramic precursor incorporated with nano γ-alumina powders to form a gel-like preceramic precursor with the aim to be used as the raw material for robocasting ceramic parts. The gel-like preceramic precursor is simply extruded for shaping by CAD design with the self-incorporated robocasting machine, and then pyrolyzed the shaped gel-like preceramic precursor at 700, 850 and 950 °C, respectively to transform from a polymeric composite to core-shell silicon oxycarbide ceramic composite that has been characterized by XRD representing an amorphous silicon oxycarbonitride structure coating on the surface of nano γ-alumina. The Vickers hardness of the core-shell silicon oxycarbide ceramic is about HV 266–300 that is two times higher than that of 7000 series aluminum alloy.