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

Abstract

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.

Effects of Microstructural Arrangement on the Mechanical Behavior of 3D Printed Polyamide

“…The authors concluded that the anisotropic behavior is mainly explained by a lower cohesion in the building direction in comparison to the other in-plane directions. Geometrical effects such as the symmetry in the filament arrangement are among the factors that prevail for controlling the mechanical behavior of printed parts [24]. In a more recent work by the authors [24], the significance of the anisotropic behavior has been proven for a composite material for which both the part orientation and printing angles were found to be important factors for inducing microstructural asymmetric/symmetric architectures.…”

“…Geometrical effects such as the symmetry in the filament arrangement are among the factors that prevail for controlling the mechanical behavior of printed parts [24]. In a more recent work by the authors [24], the significance of the anisotropic behavior has been proven for a composite material for which both the part orientation and printing angles were found to be important factors for inducing microstructural asymmetric/symmetric architectures. Because of the influence of the material discontinuities, especially the processgenerated porosities [25], in comparison to injection molding, a strong trend for considering high-value feed stock materials has been considered for improving the performance of 3D printed materials using FFF.…”