DENSE EUTECTIC CERAMIC OXIDE BY ADDITIVE MANUFACTORING: SUSTAINABLE BY-DESIGN MATERIALS AND TECHNOLOGIES (ECOBAM project)

This project, funded by European Union – Next Generation EU, consisting in finding new solutions for the production of Al2O3-based directionally solidified eutectic systems by Additive Manufacturing. Al2O3 based directionally solidified eutectics ceramics have attracted a great deal of interest over recent decades due to their superior high-temperature strength retention and creep resistance to metal alloys, and higher oxidation resistance and microstructural stability, as compared with other ceramics. For these reasons they have been considered the most promising candidates for ultra-high temperature structural applications. From the point of view of processing, oxide eutectic composite ceramics have been produced by several solidification methods which, however, cannot be used to obtain fine microstructure, large or complex shaped items. To overcome these shortcomings, additive manufacturing (AM) can be a very promising method to prepare monolithic and complex-shaped ceramic parts with fine and homogeneous microstructures. In particular Laser Power Bed Fusion (LPBF) and Direct Energy Deposition (DED) are AM technologies potentially suitable for directly shaping and sintering advanced ceramics in a single-step. This project aims to verify the applicability of these technologies to the production of Al2O3 based eutectics ceramics. In order to realize innovative eutectic ceramic matrix composites with a refined interpenetrating microstructure and good mechanical properties, optimization of eutectic system properties (morphology, particle size distribution, flowability) and printing parameters have been performed. The study focused on evaluating the printability of the eutectic Al2O3-ZrO2 composition using zirconia stabilised with 8 and 16 wt% of Y2O3. The addition of graphite to the studied compositions made it possible to evaluate its effect in the absorption of the laser beam. “This study was carried out within the « Dense Eutectic Ceramic Oxide by Additive Manufacturing; Sustainable by Design Materials and Techonogies(ECOBAM) » project – funded by European Union – Next Generation EU within the PRIN 2022 PNRR program (D.D.1409 del 14/09/2022 Ministero dell’Università e della Ricerca). This manuscript reflects only the authors’ views and opinions and the Ministry cannot be considered responsible for them