SCHLACHER: Strategies for improving the strength of 3D-printed alumina ceramics
Channel: Chair of Structural and Functional Ceramics
Date: 2022-03-11

[Title]
Strategies for improving the strength of 3D-printed alumina ceramics

[Authors]
Josef SCHLACHER
Anna-Katharina HOFER
Sebastian GEIER
Martin SCHWENTENWEIN
Tanja LUBE
Raul BERMEJO

[Event]
96th DKG Annual Meeting (DKG96)
Thursday, 22nd April 2021

[Abstract]
The Lithography-based Ceramic Manufacturing (LCM) technology has been established as novel technique for fabricating structural and functional ceramics. Much effort has been devoted to analysing the influence of the printing direction, surface finish, as well as sintering conditions on the strength distribution of 3D-printed alumina ceramics. In this work we explore a novel strategy to further enhance the strength of 3D-printed ceramics, based on a multi-material approach. The layer-by-layer capability of the LCM techniques is employed to combine alumina and alumina-zirconia ceramics in a multilayer architecture, introducing compressive residual stresses in the surface alumina layers. Biaxial bending is performed both on the 3D printed multi-material and monolithic alumina parts. Results are analysed in the framework of Weibull statistics. A characteristic biaxial strength higher than 1 GPa is measured on the multilayers, compared to 650 MPa in monolithic alumina, the difference corresponding to the magnitude of compressive residual stresses due to the thermal mismatch between material regions during cooling from sintering. This is the first report of employing additive manufacturing to tailor the strength of alumina ceramics, taking advantage of the layer-by-layer printing process. Designing complex-shaped ceramic architectures with residual stresses through additive manufacturing opens a new path for fabrication of technical ceramics with tailored mechanical properties.