Continuous carbon fibre-reinforcement in a novel laser-sintering process with glass bead reinforced matrix material

Additive manufacturing of continuous carbon fibre reinforced polymer (CCFRP) parts enables the economic production of complex parts for aerospace, engineering and other industries. With continuous fibres, the mechanical properties of parts can be significantly increased in accordance with the load path. Matrix requirements for such applications, however, can only be met optimally by laser sintering. The advantages of CCFRP and laser-sintering have been combined in a novel laser-sintering machine with automated continuous fibre integration. This paper describes the experiments to analyse the continuous fibre integration into a glass bead reinforced matrix material (PA12GF). A higher energy input during the laser sintering phase resulted in on average 15,9 % less deviation from the target dimensions and a porosity of 2,30 % depending on the laser energy density. Additionally, compared to PA12 without glass beads, warpage was reduced by almost 30%. The fibre integration remained almost unaffected if the surface temperature requirements were met. The depth of the heat affected zone was examined with a response surface (R² = 97,2 %) for optimisation with regard to the integration speed and the nozzle temperature.