Multi-material design concepts for tailoring the structural integrity of 3D-printed alumina-based ceramics
SCHLACHER J. 1, GEIER S. 2, HOFER A. 1, KRALEVA I. 1, SCHWENTENWEIN M. 2, BERMEJO R. 1
1 Department of Materials Science, Chair of Structural and Functional Ceramics, Montanuniversitaet Leoben, Leoben, Austria; 2 Lithoz GmbH, Vienna, Austria
In this work, the potential of the Lithography-based Ceramic Manufacturing (LCM) technology to design novel alumina-based ceramic systems is explored. The first approach demonstrates the use of the LCM technology to print alumina-based ceramic parts with superior strength. The combination of alumina (outer regions) with alumina-zirconia (ZTA) layers introduces compressive residual stresses in the surface layers. A characteristic biaxial strength as high as 1 GPa is measured on the alumina-based multilayers corresponding to the magnitude of in-plane residual stresses in the external alumina layers. The second approach shows the effectiveness of the multi-material design to enhance the thermal shock resistance of 3D-printed alumina-based ceramics. In this damage tolerant design, the alumina layers are embedded between ZTA-layer regions. The corresponding tailored compressive residual stresses in the embedded alumina layers act as an effective barrier to crack propagation, providing a minimum strength for the 3D architecture. It could be shown that the remaining strength after thermal shock of the multi-material ceramic is significantly higher than that of the monoliths, owed to the crack arrest capability of the embedded layers. These two case studies demonstrate the potential of the LCM technology in the design of multi-material complex architectures with tailored mechanical response under distinct loading scenarios.