3D PRINTED SHORT CARBON FIBRES REINFORCED POLYAMIDE: TENSILE AND COMPRESSIVE CHARACTERISATION AND MULTISCALE FAILURE ANALYSIS

The use of fused filament fabrication technology as a competitor of the conventional manufacturing processes for end-use parts production is of a great interest. However, a deep knowledge of the mechanical properties and failure behavior of printed parts is required to safely design final usable components. The present work aims to characterize the mechanical properties of a 3D printed short carbon fiber reinforced polyamide and to investigate the relationship between its unique morphology and its failure behavior. Tensile tests were conducted on rectangular specimens printed with an alternating sequence of layers with 0°/90° and ±45° raster orientation. Fracture surfaces of failed specimens were analyzed by Scanning Electron Microscopy (SEM). Possible failure mechanisms were then inferred by surface morphology analysis. Moreover, several specimens' geometries were designed and printed to characterize the in-plane and out-of-plane material compressive properties. Considerations about the longitudinal strength of the material were eventually drawn.