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- Multifunctional Ceramics for Aeronautical and Aerospace ApplicationsPublication . Shvydyuk, Kateryna; Nunes-Pereira, João; Rodrigues, Frederico; Pascoa, Jose; Lanceros-Mendez, Senentxu; Pereira Silva, AIn the areas of aeronautics and aerospace, ceramic composites play an essential and increasing role due to their superior performance and tailorable properties, exhibiting highly specialized mechanical, thermal, and electric features1. Their main applications include thermal protection systems (TPS), thermal barrier coatings (TBC), and dielectric barrier discharge (DBD) plasma actuators, both for instrumentation and control purposes2. This work reports the manufacture and characterization of three ceramic composites capable of fulfilling the multifunctional ceramic condition according to the aforementioned applications. Accordingly, MgO-Al2O3 (MA), MgOCaZrO3 (MCZ), and Y2O3 stabilized ZrO2 (YSZ) are introduced for TPS, TBC, and DBD dielectric elements. To this aim, MA, MCZ, and YSZ ceramic composites were fabricated via a sequential process, encompassing the selection of raw powders and milling, die pressing, and sintering. Further, the samples were polished for surface optimization. Overall, the results obtained, including mechanical (Young’s and shear moduli, flexural strength, hardness, and fracture toughness), thermal (thermal conductivity and thermal expansion (CTE)), and electrical (dielectric constant) properties, report evidence that the developed ceramics show suitable multifunctional characteristics and therefore fulfil the aeronautical and aerospace demands for increased materials performances. The combined analysis of the Young’s and shear moduli (Fig.1a) with the CTE – the latter over a wide range of temperatures (Fig. 1b) – allows concluding that the cost-effective and widely used alumina appears suitable for bulk monolithic (TPS) and joint applications (TPS, TBC, and DBD).
- Long-lasting ceramic composites for surface dielectric barrier discharge plasma actuatorsPublication . Shvydyuk, Kateryna; Rodrigues, F.F.; Nunes-Pereira, João; Pascoa, José; Lanceros-Mendez, Senentxu; Silva, A PereiraThe developed research presents a novel experimental study of the cost-effective MgO-Al2O3, MgO-CaZrO3 perovskite, and thermally stable YSZ ceramic composites for DBD plasma actuators in aerospace applications. This study focuses on the implementation of ceramic DBD plasma actuators for aerodynamic flow control and ice creation mitigation. For this purpose, electrical power consumption analysis, induced flow velocities assessment, and mechanical and thermal characterization were performed. MgO-Al2O3 presented higher induced velocities than its zirconia-based counterparts of up to 3.3 m/s, and lower heat dissipation, achieving a ceiling temperature of 46 ºC, being thereby the best-suited candidate for active flow control mechanisms. In contrast, YSZ had very high-power consumption translated into a maximum surface temperature of 155.4 ºC, establishing itself for ice mitigation. This extensive research evinces that the strategic combination of the developed ceramics’ thermomechanical, thermoelectric, and electromechanical properties allows them to be a promising breakthrough material for DBD plasma actuators.