Breaking Material Symmetry to Control Mechanical Performance in 3D Printed Objects

Additive manufacturing is a modern manufacturing technology allowing the material structuring at a fine scale. This structuring affects the performance of printed parts. In this study, the quantification of the material arrangement in 3D printed ceramic on the mechanical performance is tackled. The experimental layout considers two main printing parameters, namely, part orientation and printing angle, where 12 different printing configurations are studied. These configurations differ in terms of filament arrangement in the building direction, and within the plane of construction. Material characterisation is undertaken through tensile testing, which are performed for vertical, lateral and longitudinal orientations, and combined with a printing angle of 0°, 15°, 30°, and 45°. In addition, Scanning Electron Microscopy is considered to study how the material symmetry affects the fractured patterns. This analysis is completed with optical imaging and is used to monitor the deformation sequences up to the rupture point. The experimental results show a wide variety of deformation mechanisms that are triggered by the studied printing configurations. This study concludes on the interpretation of the observed trends in terms of mechanical load transfer, which is related to the lack of material connectivity, and the relative orientation of the filaments with respect to the loading directions. This study also concludes on the possibility to tune the tensile performance of 3D printed ceramic material by adjusting both the part orientation and the printing angle.