The effect of cross-section geometry on crushing behaviour of 3D printed continuous carbon fibre reinforced polyamide profiles

The present study has analysed the effect of cross-section geometry and the printing pattern of continuous carbon reinforced polyamide on the axial and radial crushing behaviour. Each geometry and printing pattern generated singular defects, but the most relevant microstructural aspect resulted the fibre orientation. The geometry with the re-entrant shape and Concentrical printing pattern was identified as the best profile for axial and radial crushing loadings, with a SEA of 23.9 and 5.9 kJ/kg. In spite of axial SEA values are far from those values obtained for composite profile manufactured by conventional process, radial SEA value obtained with steered fibres was at least 2-3 times higher than the best value found in the literature. Thus, concentrically 3D printed with steered fibres layers, could be exploited for radially loaded hollow profiles applications. Despite studied cross-section are not good enough under axial loads, 3D printing allows complex geometries and exploring more sophisticated cross-sections could lead to higher axial SEA values.

Automated summary

The study found that the geometry with re-entrant shape and concentrical printing pattern performed best under axial and radial crushing load, with higher specific energy absorption. Despite poor performance under axial load, 3D printing enables complex geometries and higher axial specific energy absorption values.